2040:. The difference is that protonephridia combine both filtration stages in the same organ, while metanephridia perform only the second filtration and rely on other mechanisms for the first – in annelids special filter cells in the walls of the blood vessels let fluids and other small molecules pass into the coelomic fluid, where it circulates to the metanephridia. In annelids the points at which fluid enters the protonephridia or metanephridia are on the forward side of a septum while the second-stage filter and the nephridiopore (exit opening in the body wall) are in the following segment. As a result, the hindmost segment (before the growth zone and pygidium) has no structure that extracts its wastes, as there is no following segment to filter and discharge them, while the first segment contains an extraction structure that passes wastes to the second, but does not contain the structures that re-filter and discharge urine.
1535:
5053:
2545:
4856:
3710:. Polychaetes, which these analyses found to be the parent group, have completely segmented bodies, while polychaetes' echiurans and sipunculan offshoots are not segmented and pogonophores are segmented only in the rear parts of their bodies. It now seems that segmentation can appear and disappear much more easily in the course of evolution than was previously thought. The 2007 study also noted that the ladder-like nervous system, which is associated with segmentation, is less universal than previously thought in both annelids and arthropods.
2248:-rich eggs, which reduce the time the larva needs to spend among the plankton, or eggs from which miniature adults emerge rather than larvae. The rest care for the fertilized eggs until they hatch – some by producing jelly-covered masses of eggs which they tend, some by attaching the eggs to their bodies and a few species by keeping the eggs within their bodies until they hatch. These species use a variety of methods for sperm transfer; for example, in some the females collect sperm released into the water, while in others the males have a
4766:
4835:
5013:
4897:
4992:
5073:
4797:
136:
5111:
118:
1936:
3689:. For a cross-check the study used an analysis of 11 genes (including the original 3) in ten taxa. This analysis agreed that clitellates, pogonophorans and echiurans were on various branches of the polychaete family tree. It also concluded that the classification of polychaetes into Scolecida, Canalipalpata and Aciculata was useless, as the members of these alleged groups were scattered all over the family tree derived from comparing the 81 taxa. It also placed
5217:
8809:
1455:
1374:
4941:
2174:
2122:
5209:, follow a similar pattern in the fertilized egg's development. When their cells divide after the 4-cell stage, descendants of these four cells form a spiral pattern. In these phyla the "fates" of the embryo's cells, in other words the roles their descendants will play in the adult animal, are the same and can be predicted from a very early stage. Hence this development pattern is often described as "spiral determinate
8797:
872:
865:
2054:
1967:, have evolved jaws, which can be used for seizing prey, biting off pieces of vegetation, or grasping dead and decaying matter. On the other hand, some predatory polychaetes have neither jaws nor eversible pharynges. Selective deposit feeders generally live in tubes on the sea-floor and use palps to find food particles in the sediment and then wipe them into their mouths.
1891:
the body, and the two coelomata are widely separated and run the length of the body. They function as the main blood vessels, although they are side-by-side rather than upper and lower. However, they are lined with mesothelium, like the coelomata and unlike the blood vessels of other annelids. Leeches generally use suckers at their front and rear ends to move like
1692:(the output signal lines of nerve cells). Their large diameter decreases their resistance, which allows them to transmit signals exceptionally fast. This enables these worms to withdraw rapidly from danger by shortening their bodies. Experiments have shown that cutting the giant axons prevents this escape response but does not affect normal movement.
1567:(body cavity): circular muscles make a segment longer and slimmer when they contract, while under them are longitudinal muscles, usually four distinct strips, whose contractions make the segment shorter and fatter. But several families have lost the circular muscles, and it has been suggested that the lack of circular muscles is a
4639:("jointed animals"), as segmentation is obvious in most members of both phyla. However, the genes that drive segmentation in arthropods do not appear to do the same in annelids. Arthropods and annelids both have close relatives that are unsegmented. It is at least as easy to assume that they evolved segmented bodies
1820:
1610:
chetae. The parapodia of burrowing and tube-dwelling polychaetes are often just ridges whose tips bear hooked chetae. In active crawlers and swimmers the parapodia are often divided into large upper and lower paddles on a very short trunk, and the paddles are generally fringed with chetae and sometimes with
1877:
in the body wall and around the gut transfer blood between the main blood vessels and to parts of the segment that need oxygen and nutrients. Both of the major vessels, especially the upper one, can pump blood by contracting. In some annelids the forward end of the upper blood vessel is enlarged with
1890:
and their closest relatives have a body structure that is very uniform within the group but significantly different from that of other annelids, including other members of the
Clitellata. In leeches there are no septa, the connective tissue layer of the body wall is so thick that it occupies much of
1609:
Nearly all polychaetes have parapodia that function as limbs, while other major annelid groups lack them. Parapodia are unjointed paired extensions of the body wall, and their muscles are derived from the circular muscles of the body. They are often supported internally by one or more large, thick
2353:
Terrestrial annelids can be invasive in some situations. In the glaciated areas of North
America, for example, almost all native earthworms are thought to have been killed by the glaciers and the worms currently found in those areas are all introduced from other areas, primarily from Europe, and,
2299:
and then sperm from the spermathecae. Fertilization and development of earthworm eggs takes place in the cocoon. Leeches' eggs are fertilized in the ovaries, and then transferred to the cocoon. In all clitellates the cocoon also either produces yolk when the eggs are fertilized or nutrients while
1762:
that serves as a lining) from the preceding and following segments on either side. Each mesentery is similar except that the mesothelium is the lining of each of the pair of coelomata, and the blood vessels and, in polychaetes, the main nerve cords are embedded in it. The mesothelium is made of
755:
is used less frequently by doctors than it once was, some leech species are regarded as endangered species because they have been over-harvested for this purpose in the last few centuries. Ragworms' jaws are now being studied by engineers as they offer an exceptional combination of lightness and
2467:
have come from China around 30 AD, India around 200 AD, ancient Rome around 50 AD and later throughout Europe. In the 19th century medical demand for leeches was so high that some areas' stocks were exhausted and other regions imposed restrictions or bans on exports, and
1598:, fine hair-like extensions that increase the area available for secreting the cheta. When the cheta is complete, the microvilli withdraw into the chetoblast, leaving parallel tunnels that run almost the full length of the cheta. Hence annelids' chetae are structurally different from the
1546:
fibers, usually in layers that spiral in alternating directions so that the fibers cross each other. These are secreted by the one-cell deep epidermis (outermost skin layer). A few marine annelids that live in tubes lack cuticles, but their tubes have a similar structure, and
1479:(Greek χαιτη, meaning "hair") and, in some species, appendages. The frontmost and rearmost sections are not regarded as true segments as they do not contain the standard sets of organs and do not develop in the same way as the true segments. The frontmost section, called the
995:
history: in the 19th century they were assigned to the phylum "Gephyrea", which is now empty as its members have been assigned to other phyla; the
Echiura were next regarded as annelids until the 1940s, when they were classified as a phylum in their own right; but a
1954:
that can be everted (turned inside out to extend it). In these animals the foremost few segments often lack septa so that, when the muscles in these segments contract, the sharp increase in fluid pressure from all these segments everts the pharynx very quickly. Two
7065:
This is the case for circular muscles, which have been reported as absent in many families (Opheliidae, Protodrilidae, Spionidae, Oweniidae, Aphroditidae, Acoetidae, Polynoidae, Sigalionidae, Phyllodocidae, Nephtyidae, Pisionidae, and
Nerillidae; Tzetlin
715:
that improve the effectiveness of the parapodia. In species with incomplete septa or none, the blood circulates through the main body cavity without any kind of pump, and there is a wide range of locomotory techniques – some burrowing species turn their
1845:
to crawl or swim. In these animals the septa enable the circular and longitudinal muscles to change the shape of individual segments, by making each segment a separate fluid-filled "balloon". However, the septa are often incomplete in annelids that are
2646:, found in Australia and a little older than the Burgess Shale, was possibly an annelid. However, it lacks some typical annelid features and has features which are not usually found in annelids and some of which are associated with other phyla. Then
2728:, was found that changed the hypotheses about how the annelid head developed. It appears to have bristles on its head segment akin to those along its body, as if the head simply developed as a specialized version of a previously generic segment.
1882:
some of the vessels that connect the upper and lower main vessels function as hearts. Species with poorly developed or no septa generally have no blood vessels and rely on the circulation within the coelom for delivering nutrients and oxygen.
2835:
into higher-level groups. In 1997 Greg Rouse and
Kristian Fauchald attempted a "first heuristic step in terms of bringing polychaete systematics to an acceptable level of rigour", based on anatomical structures, and divided polychaetes into:
2354:
more recently, from Asia. Northern hardwood forests are especially negatively impacted by invasive worms through the loss of leaf duff, soil fertility, changes in soil chemistry and the loss of ecological diversity. Especially of concern is
1825:
1821:
1824:
2333:
of organic matter and thus making it more quickly available to other organisms, and by concentrating minerals and converting them to forms that plants can use more easily. Earthworms are also important prey for birds ranging in size from
836:
which can grow up to 6.7 m (22 ft). Although research since 1997 has radically changed scientists' views about the evolutionary family tree of the annelids, most textbooks use the traditional classification into the following sub-groups:
2264:, and it is uncertain how they produce ova and sperm. In a few species the rear of the body splits off and becomes a separate individual that lives just long enough to swim to a suitable environment, usually near the surface, and spawn.
707:, and the vessels in segments near the front ends of these species are often built up with muscles that act as hearts. The septa of such species also enable them to change the shapes of individual segments, which facilitates movement by
1826:
1771:
fibers in the body wall. The mesothelium may also form radial and circular muscles on the septa, and circular muscles around the blood vessels and gut. Parts of the mesothelium, especially on the outside of the gut, may also form
2109:, can regenerate from a single segment, and others can regenerate even if their heads are removed. Annelids are the most complex animals that can regenerate after such severe damage. On the other hand, leeches cannot regenerate.
2255:
Some polychaetes breed only once in their lives, while others breed almost continuously or through several breeding seasons. While most polychaetes remain of one sex all their lives, a significant percentage of species are full
2232:
becomes the pygidium (tail-piece); a narrow band immediately in front of that becomes the growth zone that produces new segments; and the rest of the trochophore becomes the peristomium (the segment that contains the mouth).
2086:, seem to reproduce entirely asexually, while others reproduce asexually in summer and sexually in autumn. Asexual reproduction in oligochaetes is always by dividing into two or more pieces, rather than by budding. However,
2036:. Both of these systems use a two-stage filtration process, in which fluid and waste products are first extracted and these are filtered again to re-absorb any re-usable materials while dumping toxic and spent materials as
1474:
and
Polygordius have lost their segmentation, but these are the exceptions from the rule. Most of an annelid's body consists of segments that are practically identical, having the same sets of internal organs and external
3701:
In addition to re-writing the classification of annelids and three previously independent phyla, the molecular phylogenetics analyses undermine the emphasis that decades of previous writings placed on the importance of
1873:. Species with well-developed septa generally also have blood vessels running all long their bodies above and below the gut, the upper one carrying blood forwards while the lower one carries it backwards. Networks of
1695:
The sensors are primarily single cells that detect light, chemicals, pressure waves and contact, and are present on the head, appendages (if any) and other parts of the body. Nuchal ("on the neck") organs are paired,
1506:
The segments develop one at a time from a growth zone just ahead of the pygidium, so that an annelid's youngest segment is just in front of the growth zone while the peristomium is the oldest. This pattern is called
1720:
of arthropods' eyes. Some tube-worms use ocelli widely spread over their bodies to detect the shadows of fish, so that they can quickly withdraw into their tubes. Some burrowing and tube-dwelling polychaetes have
3697:
among the clitellates. Rouse accepted the analyses based on molecular phylogenetics, and their main conclusions are now the scientific consensus, although the details of the annelid family tree remain uncertain.
1823:
2363:
Earthworms migrate only a limited distance annually on their own, and the spread of invasive worms is increased rapidly by anglers and from worms or their cocoons in the dirt on vehicle tires or footwear.
1729:
have on the undersides of their heads palps that are used both in feeding and as "feelers", and some of these also have antennae that are structurally similar but probably are used mainly as "feelers".
8735:
Guo, Jin; Parry, Luke A.; Vinther, Jakob; Edgecombe, Gregory D.; Wei, Fan; Zhao, Jun; Zhao, Yang; Béthoux, Olivier; Lei, Xiangtong; Chen, Ailin; Hou, Xianguang; Chen, Taimin; Cong, Peiyun (2022).
1658:, is generally "ladder-like", consisting of a pair of nerve cords that run through the bottom part of the body and have in each segment paired ganglia linked by a transverse connection. From each
5654:
Struck, T. H.; Paul, C.; Hill, N.; Hartmann, S.; Hösel, C.; Kube, M.; Lieb, B.; Meyer, A.; Tiedemann, R.; Purschke, G. N.; Bleidorn, C. (2011). "Phylogenomic analyses unravel annelid evolution".
2688:. It is not until the early Ordovician that the first annelid jaws are found, thus the crown-group cannot have appeared before this date and probably appeared somewhat later. By the end of the
8081:
Conway Morris, S.; Pickerill, R.K.; Harland, T.L. (1982). "A possible annelid from the
Trenton Limestone (Ordovician) of Quebec, with a review of fossil oligochaetes and other annulate worms".
1983:
have sticky pads in the roofs of their mouths, and some of these can evert the pads to capture prey. Leeches often have an eversible proboscis, or a muscular pharynx with two or three teeth.
8590:
Aguinaldo, A. M. A.; J. M. Turbeville; L. S. Linford; M. C. Rivera; J. R. Garey; R. A. Raff; J. A. Lake (1997). "Evidence for a clade of nematodes, arthropods and other moulting animals".
4643:
as it is to assume that the ancestral protostome or bilaterian was segmented and that segmentation disappeared in many descendant phyla. The current view is that annelids are grouped with
7012:
2252:
that inject sperm into the female. There is no guarantee that this is a representative sample of polychaetes' reproductive patterns, and it simply reflects scientists' current knowledge.
3685:, of which nine were outgroups, in other words not considered closely related to annelids but included to give an indication of where the organisms under study are placed on the larger
964:
because of their simple body structure, but are now regarded as polychaetes. Some other groups of animals have been classified in various ways, but are now widely regarded as annelids:
1119:
and internally by septa ("partitions") at the same points, although in some species the septa are incomplete and in a few cases missing. Most of the segments contain the same sets of
8539:
Dunn, CW; Hejnol, A; Matus, DQ; Pang, K; Browne, WE; Smith, SA; Seaver, E; Rouse, GW; Obst, M (2008). "Broad phylogenomic sampling improves resolution of the animal tree of life".
3666:
to compare similarities and differences in one gene, presented a very different view, in which: the clitellates were an offshoot of one branch of the polychaete family tree; the
1662:
a branching system of local nerves runs into the body wall and then encircles the body. However, in most polychaetes the two main nerve cords are fused, and in the tube-dwelling
3693:, generally regarded at the time as a separate phylum, on another branch of the polychaete tree, and concluded that leeches were a sub-group of oligochaetes rather than their
1642:(local control centers) above and in front of the pharynx, linked by nerve cords either side of the pharynx to another pair of ganglia just below and behind it. The brains of
5874:
Renne, Paul R.; Deino, Alan L.; Hilgen, Frederik J.; Kuiper, Klaudia F.; Mark, Darren F.; Mitchell, William S.; Morgan, Leah E.; Mundil, Roland; Smit, Jan (7 February 2013).
1075:). It has also been shown that a rudimentary neural segmentation similar to that of annelids occurs in the early larval stage, even if these traits are absent in the adults.
1586:("limbs") of annelids that have them often bear more complex chetae at their tips – for example jointed, comb-like or hooked. Chetae are made of moderately flexible β-
914:
that stores and nourishes fertilized eggs until they hatch or, in moniligastrids, yolky eggs that provide nutrition for the embryos. The clitellates are sub-divided into:
2313:
2240:, which are almost all marine animals, are unknown, and only about 25% of the 300+ species whose lifecycles are known follow this pattern. About 14% use a similar
1646:
are generally in the prostomium, while those of clitellates are in the peristomium or sometimes the first segment behind the prostomium. In some very mobile and active
644:
research since 1997 has radically changed this scheme, viewing leeches as a sub-group of oligochaetes and oligochaetes as a sub-group of polychaetes. In addition, the
1850:
or that do not move by peristalsis or by movements of parapodia – for example some move by whipping movements of the body, some small marine species move by means of
1822:
2279:) are full hermaphrodites, although in a few leech species younger adults function as males and become female at maturity. All have well-developed gonads, and all
1025:, but in 1998 it was suggested that they are a sub-group of polychaetes. However, another analysis in 2002 suggested that myzostomids are more closely related to
1594:, each of which has a chetoblast ("hair-forming") cell at the bottom and muscles that can extend or retract the cheta. The chetoblasts produce chetae by forming
1857:
The fluid in the coelomata contains coelomocyte cells that defend the animals against parasites and infections. In some species coelomocytes may also contain a
1563:, in other words a combination of cells and non-cellular materials such as collagen. Below this are two layers of muscles, which develop from the lining of the
2329:
so that oxygen and water can penetrate it, and both surface and burrowing worms help to produce soil by mixing organic and mineral matter, by accelerating the
7035:
2025:– to organic matter that feeds themselves and their hosts, while the worms extend their palps into the gas flows to absorb the gases needed by the bacteria.
3887:
3726:
1764:
256:
6545:"A close phylogenetic relationship between Sipuncula and Annelida evidenced from the complete mitochondrial genome sequence of Phascolosoma esculenta"
3678:, were placed on other branches of the polychaete tree. Subsequent molecular phylogenetics analyses on a similar scale presented similar conclusions.
4265:
327:
10421:
4018:
3901:
3815:
3739:
3722:
2824:
1163:, and molt until the arthropods reach their full size. Most annelids have closed circulatory systems, where the blood makes its entire circuit via
735:. The burrowing of marine polychaetes, which may constitute up to a third of all species in near-shore environments, encourages the development of
272:
251:
11065:
1854:(fine muscle-powered hairs) and some burrowers turn their pharynges (throats) inside out to penetrate the sea-floor and drag themselves into it.
942:, mainly on fish, while most freshwater species are predators. They have suckers at both ends of their bodies, and use these to move rather like
6981:
6654:
Mitochondrial Genome
Evolution in Annelida—A Systematic Study on Conservative and Variable Gene Orders and the Factors Influencing its Evolution
2437:
sometimes find that worms are more effective bait than artificial flies, and worms can be kept for several days in a tin lined with damp moss.
972:
were first discovered in 1914, and their lack of a recognizable gut made it difficult to classify them. They have been classified as a separate
8311:
1606:, which are made of the more rigid α-chitin, have a single internal cavity, and are mounted on flexible joints in shallow pits in the cuticle.
1059:
characters. Phylogenetic analyses based on 79 ribosomal proteins indicated a position of
Sipuncula within Annelida. Subsequent analysis of the
11091:
8188:
A group of worms classified by some as polychaetes and by others as clitellates, see Rouse & Fauchald (1997) "Cladistics and polychaetes"
7803:
2221:
8035:"Palaeosols in the upper Narrabeen Group of New South Wales as evidence of Early Triassic palaeoenvironments without exact modern analogues"
7829:"Inconsistencies in proposed annelid affinities of early biomineralized organism Cloudina (Ediacaran): structural and ontogenetic evidences"
2225:
7591:
1950:
Feeding structures in the mouth region vary widely, and have little correlation with the animals' diets. Many polychaetes have a muscular
6642:
5859:
1534:
11188:
1869:
in others (dissolved in the plasma) – and provide oxygen transport within their segments. Respiratory pigment is also dissolved in the
1688:
have a different system, in which one neuron controls a group of muscle fibers. Most annelids' longitudinal nerve trunks include giant
6099:
1582:
and other capabilities. The simplest are unjointed and form paired bundles near the top and bottom of each side of each segment. The
7957:
2667:, and concluded that it was the oldest annelid known to date. There has been vigorous debate about whether the Burgess Shale fossil
11039:
7828:
1986:
The gut is generally an almost straight tube supported by the mesenteries (vertical partitions within segments), and ends with the
11078:
10127:
1483:(Greek προ- meaning "in front of" and στομα meaning "mouth") contains the brain and sense organs, while the rearmost, called the
2517:
salts. These advantages have attracted the attention of engineers. Investigations showed that ragworm jaws are made of unusual
8701:
656:, previously regarded as separate phyla, are now regarded as sub-groups of polychaetes. Annelids are considered members of the
8713:
8011:
7732:
7680:
7603:
7568:
7541:
7514:
7470:
7411:
7386:
7352:
7321:
7287:
7256:
7225:
7145:
7058:
6921:
6890:
6859:
6828:
6803:
6772:
6703:
6373:
6335:
6304:
6270:
6082:
1571:
character in
Annelida. Some annelids also have oblique internal muscles that connect the underside of the body to each side.
7668:
1499:(Greek περι- meaning "around" and στομα meaning "mouth"), is regarded by some zoologists as not a true segment, but in some
11083:
1927:
in polychaetes. The gills of tube-dwellers and burrowers usually cluster around whichever end has the stronger water flow.
2456:
Scientists study aquatic annelids to monitor the oxygen content, salinity and pollution levels in fresh and marine water.
11183:
7070:. 2002). Tzetlin and Filippova (2005) suggest that absence of circular muscles is possibly plesiomorphic in the Annelida.
2799:, have been tentatively classified as oligochaetes, but these identifications are uncertain and some have been disputed.
2699:, fossils of most of the modern mobile polychaete groups had appeared. Many fossil tubes look like those made by modern
8841:
5956:
2445:, and there have been proposals to farm them in order to reduce over-fishing of their natural populations. Some marine
924:. Oligochaetes have a sticky pad in the roof of the mouth. Most are burrowers that feed on wholly or partly decomposed
844:(about 12,000 species). As their name suggests, they have multiple chetae ("hairs") per segment. Polychaetes have
7558:
8515:
7531:
7502:
5197:
The "Lophotrochozoa" hypothesis is also supported by the fact that many phyla within this group, including annelids,
11150:
11018:
8878:
5726:"The earliest annelids: Lower Cambrian polychaetes from the Sirius Passet Lagerstätte, Peary Land, North Greenland"
2093:
Most polychaetes and oligochaetes also use similar mechanisms to regenerate after suffering damage. Two polychaete
3151:, which are distinguished by having long grooved palps that they use for feeding, and most of which live in tubes.
703:
show no obvious signs of segmentation. In species with well-developed septa, the blood circulates entirely within
11096:
11031:
8873:
1650:
the brain is enlarged and more complex, with visible hindbrain, midbrain and forebrain sections. The rest of the
7436:
597:. The species exist in and have adapted to various ecologies – some in marine environments as distinct as
8957:
8947:
8930:
2181:
1373:
8426:"Combined-data phylogenetics and character evolution of Clitellata (Annelida) using 18S rDNA and morphology"
771:
fossils may represent annelids, the oldest known fossil that is identified with confidence comes from about
7913:
Budd, G. E.; Jensen, S. (May 2000). "A critical reappraisal of the fossil record of the bilaterian phyla".
6145:
Struck, T.H.; Schult, N.; Kusen, T.; Hickman, E.; Bleidorn, C.; McHugh, D.; Halanych, K.M. (5 April 2007).
1684:, and the speed and power of the fiber's contractions depends on the combined effects of all its neurons.
10974:
10961:
10120:
5818:
764:
8168:
6653:
17:
7696:
5829:
2260:
or change sex during their lives. Most polychaetes whose reproduction has been studied lack permanent
11106:
10264:
7749:
7628:
Scaps, P. (February 2002). "A review of the biology, ecology and potential use of the common ragworm
2652:
1462:
821:
135:
10979:
8502:. Vol. 1: Annelida Basal Groups and Pleistoannelida, Sedentaria I. De Gruyter. pp. 37–68.
8307:
7084:"Challenging received wisdoms: Some contributions of the new microscopy to the new animal phylogeny"
5875:
808:, are the remains of oligochaetes, and the earliest indisputable fossils of the group appear in the
8161:"Annelida. Annelida. Segmented worms: bristleworms, ragworms, earthworms, leeches and their allies"
6504:"Spiralian Phylogenomics Supports the Resurrection of Bryozoa Comprising Ectoprocta and Entoprocta"
2534:
1975:
that wash food particles towards their mouths. Non-selective deposit feeders ingest soil or marine
1908:
11155:
7796:
5823:
2509:
Ragworms' jaws are strong but much lighter than the hard parts of many other organisms, which are
864:
10349:
8962:
5844:
3663:
2121:
997:
820:
There are over 22,000 living annelid species, ranging in size from microscopic to the Australian
6937:
Paxton, H. (June 2005). "Molting polychaete jaws—ecdysozoans are not the only molting animals".
3747:, the clade containing nearly all of annelid diversity, divided into two highly diverse groups:
10901:
10113:
8834:
8034:
3788:
3703:
3686:
2241:
1767:
cells; in other words, their bodies form part of the epithelium but their bases extend to form
1651:
1579:
1112:
680:
11132:
8737:"A Cambrian tommotiid preserving soft tissues reveals the metameric ancestry of lophophorates"
7996:
5725:
11127:
10577:
10227:
8925:
8287:
8268:
5636:
5237:
4636:
3157:, the most active polychaetes, which have parapodia reinforced by internal spines (aciculae).
2869:
2582:, but the similarities are too vague for these fossils to be classified with confidence. The
2557:
1841:(waves of contraction and expansion that sweep along the body), or flex the body while using
856:. Most are marine animals, although a few species live in fresh water and even fewer on land.
760:
476:
228:
11142:
11119:
2350:, and in some cases conserving earthworms may be essential for conserving endangered birds.
1515:, have fixed maximum numbers of segments, while others add segments throughout their lives.
10987:
10948:
10242:
8748:
8654:
8599:
8548:
8345:
8214:
8090:
8049:
7761:
6819:
Anderson, D. T. (1998). "The Annelida and their close relatives". In Anderson, D.T. (ed.).
6456:
6158:
5890:
5779:
5663:
4640:
2280:
1717:
938:-shaped" and whose best known members are leeches. Marine species are mostly blood-sucking
826:
11070:
7378:
7372:
7344:
7338:
7313:
7307:
7279:
7273:
7248:
7242:
7217:
7211:
7137:
7131:
6913:
6907:
6882:
6876:
6851:
6845:
6795:
6789:
6764:
6758:
6365:
6359:
6327:
6321:
6074:
6068:
2610:
belong). Until 2008 the earliest fossils widely accepted as annelids were the polychaetes
8:
5721:
5052:
2700:
2647:
2583:
2544:
2429:
that tunnels through coral, detaches in order to spawn at the surface, and the people of
1858:
1847:
1747:
879:
751:. Scientists observe annelids to monitor the quality of marine and fresh water. Although
609:
10105:
8752:
8658:
8603:
8552:
8458:
8349:
8218:
8094:
8053:
7844:
7765:
6460:
6162:
5894:
5849:
5783:
5667:
2367:
Marine annelids may account for over one-third of bottom-dwelling animal species around
1111:
phyla, but they have a distinctive combination of features. Their bodies are long, with
10939:
10572:
10254:
9390:
8942:
8920:
8908:
8883:
8813:
8623:
8572:
8521:
8480:
8406:
8371:
8136:
8132:
7938:
7926:
7895:
7777:
7750:"Decay and preservation of polychaetes; taphonomic thresholds in soft-bodied organisms"
7649:
7004:
6962:
6736:
6620:
6595:
6571:
6544:
6425:
6181:
6146:
5914:
5748:
5687:
4791:
3718:
2470:
2014:
1659:
1655:
1591:
1128:
992:
832:
712:
695:
separate the segments of many species, but are poorly defined or absent in others, and
130:
7723:
Rouse, G. (1998). "The Annelida and their close relatives". In Anderson, D. T. (ed.).
7461:
Rouse, G. (1998). "The Annelida and their close relatives". In Anderson, D. T. (ed.).
6694:
Rouse, G. (1998). "The Annelida and their close relatives". In Anderson, D. T. (ed.).
6261:
Rouse, G. (1998). "The Annelida and their close relatives". In Anderson, D. T. (ed.).
11178:
11114:
10364:
9812:
9732:
9082:
8952:
8915:
8903:
8893:
8827:
8774:
8766:
8709:
8682:
8677:
8642:
8615:
8564:
8525:
8511:
8442:
8425:
8363:
8242:
8237:
8202:
8007:
7930:
7891:
7728:
7676:
7599:
7564:
7537:
7510:
7466:
7432:
7407:
7382:
7348:
7317:
7283:
7252:
7221:
7192:
7184:
7141:
7105:
7054:
7000:
6954:
6950:
6917:
6906:
Ruppert, E. E.; Fox, R. S. & Barnes, R. D. (2004). "Onychophora and Tardigrada".
6886:
6855:
6824:
6799:
6768:
6757:
Ruppert, E. E.; Fox, R. S. & Barnes, R. D. (2004). "Introduction to Arthropoda".
6699:
6625:
6576:
6525:
6484:
6479:
6444:
6417:
6369:
6331:
6300:
6295:
Rouse, G. (1998). "The Annelida and their close relatives". In Anderson, D.T. (ed.).
6266:
6186:
6078:
5952:
5906:
5797:
5679:
5210:
3714:
2612:
2510:
2491:
2356:
1751:
1560:
1014:, mainly as parasites. In the past they have been regarded as close relatives of the
688:
602:
8484:
8375:
8140:
7942:
7899:
7781:
7653:
6966:
6740:
6429:
5752:
4855:
4765:
2375:. Burrowing species increase the penetration of water and oxygen into the sea-floor
10640:
10519:
10411:
10354:
10294:
10289:
10217:
10202:
8867:
8801:
8756:
8672:
8662:
8627:
8607:
8576:
8556:
8503:
8470:
8437:
8410:
8398:
8353:
8283:
8232:
8222:
8128:
8098:
8057:
7972:
7922:
7887:
7836:
7769:
7641:
7174:
7095:
7047:
Minelli, Alessandro (2009), "Chapter 6. A gallery of the major bilaterian clades",
7008:
6996:
6946:
6728:
6615:
6607:
6566:
6556:
6515:
6474:
6464:
6407:
6220:
6176:
6166:
5944:
5918:
5898:
5787:
5740:
5691:
5671:
4699:
4140:
2832:
2831:. For many years there was no clear arrangement of the approximately 80 polychaete
2719:
2406:
2380:
2300:
they are developing. All clitellates hatch as miniature adults rather than larvae.
2006:
1956:
1943:
1773:
1670:
1611:
981:
925:
782:
period. Fossils of most modern mobile polychaete groups appeared by the end of the
530:
492:
427:
293:
9086:
8589:
8424:
Marotta, Roberto; Ferraguti, Marco; Erséus, Christer; Gustavsson, Lena M. (2008).
8389:
Weigert, Anne; Bleidorn, Christoph (2015). "Current status of annelid phylogeny".
8196:
8194:
4834:
1990:
on the underside of the pygidium. However, in members of the tube-dwelling family
1495:, generally on the underside. The first section behind the prostomium, called the
1043:
was originally classified as annelids, despite the complete lack of segmentation,
683:. Each segment has the same sets of organs and, in most polychates, has a pair of
10953:
10813:
10718:
10680:
10635:
10567:
10324:
10284:
10269:
10162:
10093:
9999:
9850:
9753:
9610:
9143:
8334:"The Evolution of Annelids Reveals Two Adaptive Routes to the Interstitial Realm"
8074:
7990:
7988:
7986:
7272:
Ruppert, E.E.; Fox, R.S. & Barnes, R.D. (2004). "Introduction to Bilateria".
7048:
5766:
Bobrovskiy, I.; Nagovitsyn, A.; Hope, J. M.; Luzhnaya, E.; Brocks, J. J. (2022).
5233:
5012:
4954:
4896:
4461:
4071:
3744:
2747:
2569:
1759:
1313:
Coelom; but this is reduced or missing in many leeches and some small polychaetes
1120:
961:
957:
830:, which can both grow up to 3 meters (9.8 ft) long to the largest annelid,
364:
278:
10966:
7797:"A Revised Morphology of Cloudina with Ecological and Phylogenetic Implications"
6788:
Ruppert, E. E.; Fox, R. S. & Barnes, R. D. (2004). "Echiura and Sipuncula".
6719:
Cutler, B. (August 1980). "Arthropod cuticle features and arthropod monophyly".
5833:. Vol. 2 (9th ed.). New York: Charles Scribner's Sons. pp. 65–72.
5072:
4796:
11026:
11013:
10873:
10818:
10808:
10650:
10464:
10416:
10329:
10304:
10299:
10279:
10274:
10177:
10167:
9758:
9736:
9554:
9466:
9444:
9407:
8898:
8647:
Proceedings of the National Academy of Sciences of the United States of America
8498:
Struck TH (2019). "Phylogeny". In Purschke G, Böggemann M, Westheide W (eds.).
8207:
Proceedings of the National Academy of Sciences of the United States of America
8191:
7210:
Ruppert, E.E.; Fox, R.S. & Barnes, R.D. (2004). "Introduction to Metazoa".
6449:
Proceedings of the National Academy of Sciences of the United States of America
5274:
5264:
4878:
4810:
4660:
3939:
3924:
3404:
2746:, and it has been suggested that these animals evolved around the same time as
2724:
2703:
polychaetes, but the first tubes clearly produced by polychaetes date from the
2618:
2549:
2418:
2335:
2318:
2317:(1881) presented the first scientific analysis of earthworms' contributions to
2308:
2033:
2022:
2010:
1968:
1939:
1140:
1132:
1034:
977:
902:
or parapodia. However, they have a unique reproductive organ, the ring-shaped
744:
657:
213:
8761:
8736:
8507:
8402:
8358:
8333:
8061:
7983:
7773:
7645:
7179:
7162:
5792:
5767:
3694:
898:(about 10,000 species ). These have few or no chetae per segment, and no
11172:
10597:
10582:
10544:
10469:
10405:
10391:
10339:
10334:
10248:
10237:
10232:
10212:
10207:
10182:
9903:
9807:
9306:
8770:
7701:
7402:
Hickman, Cleveland; Roberts, L.; Keen, S.; Larson, A.; Eisenhour, D. (2007).
7188:
6561:
5854:
5418:
5225:
5110:
4991:
4722:
4624:
4476:
4153:
3148:
2945:
2715:
2689:
2657:
2623:
2495:
2464:
2330:
2257:
2029:
1964:
1892:
1866:
1725:(tilt and balance sensors) that indicate which way is down. A few polychaete
1701:
1568:
1124:
1060:
1052:
1047:
and other annelid characters. The phylum Sipuncula was later allied with the
953:
943:
853:
783:
752:
369:
70:
8643:"Evolution of the bilaterian body plan: What have we learned from annelids?"
8227:
8114:
8112:
7976:
6520:
6503:
6469:
5948:
5902:
2321:. Some burrow while others live entirely on the surface, generally in moist
731:
both as prey and in some regions are important in aeration and enriching of
10924:
10793:
10788:
10763:
10738:
10728:
10655:
10524:
10398:
10359:
10344:
10319:
10314:
10259:
10192:
10009:
10004:
9892:
9748:
9634:
9520:
9423:
9402:
9272:
9223:
9179:
9160:
8778:
8686:
8667:
8568:
8367:
7934:
7196:
7109:
6958:
6629:
6580:
6529:
6421:
6412:
6395:
6190:
6171:
5910:
5801:
5683:
5456:
5245:
5241:
4964:
4726:
4691:
4399:
4280:
4168:
4119:
3780:
3764:
3707:
3667:
3572:
3022:
2889:
2762:
2483:
2217:
2099:
1991:
1870:
1713:
1164:
1108:
1080:
1072:
969:
899:
849:
748:
704:
645:
621:
613:
605:, others in fresh water, and yet others in moist terrestrial environments.
467:
357:
332:
303:
8619:
8246:
8203:"Molecular evidence that echiurans and pogonophorans are derived annelids"
6488:
6445:"Molecular evidence that echiurans and pogonophorans are derived annelids"
6396:"Unsegmented Annelids? Possible Origins of Four Lophotrochozoan Worm Taxa"
5863:. Vol. 2 (11th ed.). Cambridge University Press. pp. 72–73.
5744:
5652:
Since this section was written, a new paper has revised the 2007 results:
2564:' fossil record consists mainly of the jaws that some species had and the
2360:
and at least one state (Wisconsin) has listed it as a prohibited species.
1935:
11052:
10933:
10848:
10823:
10768:
10743:
10665:
10660:
10625:
10615:
10309:
10222:
9970:
9941:
9927:
9917:
9502:
9318:
9231:
9013:
8109:
7840:
7100:
7083:
6611:
6225:
6208:
5876:"Time Scales of Critical Events Around the Cretaceous-Paleogene Boundary"
5822:
5563:
5253:
4987:
4891:
4743:
4656:
4612:
4505:
4386:
4204:
3995:
3843:
3784:
3730:
3301:
2973:
2904:
2816:
2794:
2785:
2779:
2732:
2714:. In 2012, a 508 million year old species of annelid found near the
2683:
2634:
2607:
2593:
2574:
2450:
2442:
2422:
2395:
2322:
2284:
2206:
2105:
2076:
2001:, which can make up 15% of the worms' total weight. The bacteria convert
1838:
1830:
1755:
1708:("little eyes") that detect the direction from which light is coming and
1496:
1471:
1470:
In addition to Sipuncula and Echiura, also lineages like Lobatocerebrum,
1213:
1096:
1064:
1003:
917:
907:
803:
794:
708:
633:
459:
414:
347:
283:
266:
261:
45:
8560:
8475:
8459:"Phylogeny of basal descendants of cocoon-forming annelids (Clitellata)"
5675:
2807:
Traditionally the annelids have been divided into two major groups, the
2756:
2598:, has been classified by some authors as an annelid, but by others as a
2075:
off a new individual while the parent remains a complete organism. Some
1503:
the peristomium has chetae and appendages like those of other segments.
1116:
10881:
10843:
10773:
10753:
10748:
10733:
10703:
10675:
10630:
10620:
10592:
10587:
10529:
10504:
10197:
10172:
10067:
10052:
10047:
10028:
10023:
9951:
9898:
9868:
9860:
9802:
9676:
9668:
9651:
9431:
9343:
9296:
9236:
9198:
9172:
9018:
9003:
7874:
Dzik, J. (2004). "Anatomy and relationships of the Early Cambrian worm
6732:
5547:
5474:
5349:
5216:
5068:
5048:
4974:
4652:
4648:
4628:
4620:
4616:
4501:
4216:
3783:
polychaetes, and several archiannelids. Some small groups, such as the
3760:
3756:
3748:
3277:
2812:
2808:
2789:
2751:
2678:
2579:
2561:
2503:
2446:
2426:
2399:
2391:
2372:
2368:
2268:
2237:
2173:
2081:
2068:
2058:
1980:
1916:
1912:
1862:
1793:
1709:
1685:
1647:
1643:
1595:
1500:
1480:
1292:
1208:
1022:
1011:
921:
895:
841:
798:
728:
669:
661:
641:
629:
628:
for locomotion. Most textbooks still use the traditional division into
625:
598:
408:
394:
374:
317:
193:
117:
90:
55:
8819:
6389:
6387:
6385:
6202:
6200:
2189:
It is thought that annelids were originally animals with two separate
1115:
that are divided externally by shallow ring-like constrictions called
11057:
11000:
10798:
10778:
10670:
10549:
10484:
10474:
10459:
10454:
10435:
10187:
10033:
9980:
9975:
9946:
9935:
9884:
9879:
9831:
9743:
9530:
9525:
9487:
9336:
9328:
9257:
9209:
9130:
9117:
9098:
9093:
9052:
8611:
7370:
7336:
7305:
7129:
7125:
7123:
7121:
7119:
6905:
6875:
Ruppert, E. E.; Fox, R. S. & Barnes, R. D. (2004). "Arthropoda".
6874:
6843:
6787:
6756:
6319:
6066:
5504:
5257:
5202:
5007:
4940:
4830:
4760:
4756:
4678:
4664:
4632:
4374:
4312:
4229:
4091:
4034:
3828:
3768:
3734:
3690:
3326:
3245:
3154:
3139:, less than 1,000 burrowing species that look rather like earthworms.
3136:
3112:
3070:
3009:
2958:
2820:
2709:
2694:
2662:
2642:
2628:
2603:
2599:
2288:
2272:
2228:
becomes the prostomium (head); a small area round the trochophore's
2202:
2002:
1995:
1960:
1924:
1904:
1879:
1874:
1842:
1813:
1722:
1677:
1603:
1583:
1508:
1488:
1317:
1198:
1156:
1144:
1092:
1040:
1026:
1015:
931:
903:
887:
883:
845:
809:
788:
773:
768:
736:
700:
684:
673:
653:
590:
443:
432:
420:
400:
337:
322:
298:
183:
170:
147:
107:
95:
10895:
8102:
6357:
6290:
6288:
6286:
6284:
6282:
2741:
2394:
that can be very dangerous to their hosts. Some small tube-dwelling
1083:, a group of extremely simplified parasites traditionally placed in
11005:
10918:
10853:
10833:
10828:
10803:
10783:
10758:
10723:
10713:
10708:
10539:
10514:
10494:
10154:
10057:
10041:
9964:
9956:
9911:
9874:
9855:
9844:
9826:
9820:
9681:
9622:
9598:
9495:
9376:
9265:
9149:
9040:
9031:
8937:
8808:
7741:
7371:
Ruppert, E. E.; Fox, R. S. & Barnes, R. D. (2004). "Annelida".
7337:
Ruppert, E. E.; Fox, R. S. & Barnes, R. D. (2004). "Annelida".
7306:
Ruppert, E. E.; Fox, R. S. & Barnes, R. D. (2004). "Annelida".
7130:
Ruppert, E. E.; Fox, R. S. & Barnes, R. D. (2004). "Annelida".
6844:
Ruppert, E. E.; Fox, R. S. & Barnes, R. D. (2004). "Nemertea".
6594:
Wanninger, Andreas; Kristof, Alen; Brinkmann, Nora (Jan–Feb 2009).
6382:
6320:
Ruppert, E. E.; Fox, R. S. & Barnes, R. D. (2004). "Annelida".
6197:
6067:
Ruppert, E. E.; Fox, R. S. & Barnes, R. D. (2004). "Annelida".
5366:
5288:
5206:
5106:
4935:
4778:
4730:
4327:
4104:
4081:
3776:
3772:
3752:
3671:
3170:
3037:
2988:
2925:
2774:
2736:
2704:
2637:
2587:
2402:
2376:
2213:
2071:
can reproduce asexually, by dividing into two or more pieces or by
1998:
1976:
1801:
1781:
1543:
1484:
1454:
1328:
1203:
1148:
1088:
1048:
1018:
939:
779:
721:
342:
308:
288:
203:
85:
80:
65:
60:
50:
11044:
7426:
7271:
7240:
7209:
7116:
6689:
6687:
6685:
6683:
6681:
6358:
Ruppert, E. E.; Fox, R. S. & Barnes, R.D. (2004). "Annelida".
2773:
pellets may be evidence that earthworms were present in the early
1742:(body cavities) in each segment, separated from other segments by
10838:
10534:
10509:
10499:
10489:
10445:
10382:
9993:
9985:
9922:
9836:
9656:
9643:
9567:
9512:
9437:
8119:
Rouse, G. W.; Fauchald, K. (1997). "Cladistics and polychaetes".
6679:
6677:
6675:
6673:
6671:
6669:
6667:
6665:
6663:
6661:
6393:
6279:
6256:
6140:
6138:
6136:
6134:
6132:
6130:
6128:
6126:
5768:"Guts, gut contents, and feeding strategies of Ediacaran animals"
5519:
5322:
5198:
5035:
4850:
4644:
4414:
3681:
In 2007 Torsten Struck and colleagues compared three genes in 81
3478:
3142:
2935:
2857:
2674:
2669:
2565:
2518:
2514:
2438:
2434:
2276:
2072:
2062:
2018:
1951:
1805:
1797:
1639:
1635:
1555:
in the epidermis protect their skins. Under the epidermis is the
1193:
1136:
1084:
1068:
1044:
1030:
1007:
988:
717:
696:
665:
649:
586:
582:
451:
352:
100:
75:
8423:
7456:
7454:
7452:
7450:
7448:
7427:
Ruppert, E.E.; Fox, R.S. & Barnes, R.D. (2004). "Mollusca".
7241:
Ruppert, E.E.; Fox, R.S. & Barnes, R.D. (2004). "Annelida".
6254:
6252:
6250:
6248:
6246:
6244:
6242:
6240:
6238:
6236:
5765:
5224:
Fossil discoveries lead to the hypothesis that Annelida and the
1578:("hairs") of annelids project out from the epidermis to provide
10698:
10690:
10559:
10062:
9796:
8996:
8983:
8854:
8851:
8796:
6973:
6812:
5848:
5260:
5249:
5229:
4695:
3675:
2766:
2487:
2347:
2220:
into miniature adults: the part of the trochophore between the
1789:
1768:
1743:
1739:
1705:
1681:
1587:
1564:
1556:
1476:
1160:
1147:
by cells in the skin underneath, is made of tough but flexible
973:
740:
692:
617:
578:
157:
8262:
8260:
8258:
8256:
7716:
7301:
7299:
7234:
6982:"Proposing a solution to the Articulata–Ecdysozoa controversy"
6658:
6123:
5716:
5714:
5712:
3771:
and some archiannelids, as well as several polychaete groups.
10607:
10479:
8160:
8080:
7445:
7366:
7364:
7203:
7161:
Bok, Michael J.; Macali, Armando; Garm, Anders (2024-04-08).
6752:
6750:
6233:
6209:"Book Review: Reproductive Biology and Phylogeny of Annelida"
4509:
3682:
3330:
2828:
2770:
2499:
2479:
2460:
2449:' predation on molluscs causes serious losses to fishery and
2430:
2387:
2343:
2339:
2296:
2261:
2249:
2209:
2198:
2094:
2087:
2037:
1972:
1887:
1851:
1777:
1726:
1697:
1663:
1631:
1615:
1552:
1548:
1519:
1512:
1296:
1056:
935:
871:
637:
594:
563:
436:
7500:
7330:
6313:
5934:
5932:
5930:
5928:
2314:
The Formation of Vegetable Mould Through the Action of Worms
1733:
1700:
structures found only in polychaetes, and are thought to be
1669:
the single nerve chord has no ganglia and is located in the
1087:, are actually reduced annelids. Research suggest that also
956:, minute annelids that live in the spaces between grains of
767:
tubes that some of the species secreted. Although some late
10992:
10645:
10137:
8491:
8253:
8026:
7296:
6147:"Annelid phylogeny and the status of Sipuncula and Echiura"
6062:
6060:
6058:
6056:
6054:
6052:
6050:
6048:
6046:
6044:
6042:
6040:
6038:
6036:
6034:
6032:
6030:
6028:
6026:
6024:
6022:
6020:
6018:
6016:
6014:
6012:
6010:
5709:
4668:
4663:. Meanwhile, arthropods are now regarded as members of the
4631:. Within the protostomes, annelids used to be grouped with
3651:
Annelid groups and phyla incorporated into Annelida (2007;
2522:
2475:
2441:
are commercially important as bait and as food sources for
2326:
2292:
2245:
2229:
2194:
2053:
1987:
1920:
1878:
muscles to form a heart, while in the forward ends of many
1809:
1689:
1619:
1599:
1575:
1492:
1342:
1233:
1152:
911:
732:
554:
542:
533:
504:
7496:
7494:
7492:
7490:
7488:
7486:
7484:
7482:
7361:
6868:
6747:
6353:
6351:
6349:
6347:
6008:
6006:
6004:
6002:
6000:
5998:
5996:
5994:
5992:
5990:
5248:
of annelids. Both groups share in common: the presence of
3674:, which for a few decades had been regarded as a separate
2032:
to remove soluble waste products, while those without use
1923:
associated with most segments, often as extensions of the
1716:
that can probably form images. The compound eyes probably
1680:, each muscle fiber (cell) is controlled by more than one
1135:
makes them inter-dependent. Their bodies are covered by a
10135:
7915:
Biological Reviews of the Cambridge Philosophical Society
7265:
6593:
5925:
3657:
Highlights major changes to traditional classifications.
2190:
1785:
548:
510:
498:
8734:
7401:
6837:
6144:
5720:
1079:
Mitogenomic and phylogenomic analysis also implies that
9786:
7949:
7479:
6781:
6344:
5987:
1000:
analysis in 1997 concluded that echiurans are annelids.
7556:
5873:
5653:
5228:
are more closely related to each other than any other
2390:
do little direct harm to their victims, some transmit
8704:. In Hall, B.K.; Pearson, R.D.; Müller, G.B. (eds.).
8640:
8159:
Rouse, G. W.; Pleijel, F.; McHugh, D. (August 2002).
7533:
Invertebrate conservation and agricultural ecosystems
7406:(4th ed.). New York: Mc Graw Hill. p. 204.
6899:
6394:
Halanych, K. M.; Dahlgren, T. G.; McHugh, D. (2002).
1704:. Some polychaetes also have various combinations of
1063:'s DNA has confirmed their close relationship to the
743:
to penetrate the sea floor. In addition to improving
727:
Earthworms are oligochaetes that support terrestrial
539:
516:
501:
8276:
Annual Review of Ecology, Evolution, and Systematics
7869:
7867:
7865:
7863:
7861:
7589:
5543:
5470:
5414:
5345:
5318:
2677:
or an annelid. Polychaetes diversified in the early
2482:. More recently leeches have been used to assist in
1895:. The anus is on the upper surface of the pygidium.
1107:
No single feature distinguishes Annelids from other
551:
545:
513:
507:
8538:
8310:. University of California Museum of Paleontology.
7623:
7621:
5939:Rouse, G. W. (2002). "Annelida (Segmented Worms)".
3145:, the great majority of polychaetes, divided into:
1994:the gut is blocked by a swollen lining that houses
1529:
536:
495:
8158:
7997:"Evolution of terrestrial burrowing invertebrates"
3791:, but belong to either one of these large groups.
3629:some "Scolecida", "Canalipalpata" and "Aciculata"
1979:via mouths that are generally unspecialized. Some
980:. More recently they have been re-classified as a
8457:Christoffersen, Martin Lindsey (1 January 2012).
8154:
8152:
8150:
8118:
7858:
7431:(7th ed.). Brooks / Cole. pp. 290–291.
5974:
5972:
5970:
5968:
11170:
10422:Archaeal Richmond Mine acidophilic nanoorganisms
8332:Struck, T.; Golombek, Anja; et al. (2015).
8300:
7618:
7501:Siddall, M. E.; Borda, E.; Rouse, G. W. (2004).
6100:"Diversity of Soil Fauna and Ecosystem Function"
4671:"), along with some phyla that are unsegmented.
2379:, which encourages the growth of populations of
976:, Pogonophora, or as two phyla, Pogonophora and
8388:
7163:"High-resolution vision in pelagic polychaetes"
6818:
5978:
1942:tube worms have no gut and gain nutrients from
815:
812:period, which began 66 million years ago.
793:. Palaeontologists disagree about whether some
763:, their fossils are rare – mostly jaws and the
125:Annelida and some examples of their diversity.
8456:
8331:
8147:
7955:
7536:. Cambridge University Press. pp. 44–46.
7050:Perspectives in Animal Phylogeny and Evolution
5965:
2417:Earthworms make a significant contribution to
2043:
10121:
8835:
7509:. Oxford University Press. pp. 237–248.
7465:. Oxford University Press. pp. 196–202.
7160:
6823:. Oxford University Press. pp. 183–196.
6698:. Oxford University Press. pp. 183–196.
6542:
6299:. Oxford University Press. pp. 179–183.
6265:. Oxford University Press. pp. 176–179.
2433:regard these spawning modules as a delicacy.
6543:Shen, X.; Ma, X.; Ren, J.; Zhao, F. (2009).
6495:
5938:
2815:. In turn the clitellates were divided into
2474:is treated as an endangered species by both
2283:. Earthworms store their partners' sperm in
2090:have never been seen reproducing asexually.
1919:(the group to which earthworms belong) have
1625:
679:The basic annelid form consists of multiple
9222:
7505:. In Cracraft, J.; Donoghue, M. J. (eds.).
3129:Morphological phylogeny of Annelida (1997)
2383:and small animals alongside their burrows.
1538:Internal anatomy of a segment of an annelid
1487:(Greek πυγιδιον, meaning "little tail") or
711:("ripples" that pass along the body) or by
567:
10128:
10114:
9196:
8842:
8828:
8728:
8641:Shankland, M.; Seaver, E.C. (April 2000).
7912:
7747:
6718:
2412:
2303:
2172:
1453:
1102:
870:
720:inside out to drag themselves through the
116:
9389:
8760:
8676:
8666:
8474:
8441:
8430:Zoological Journal of the Linnean Society
8357:
8236:
8226:
8032:
7994:
7958:"Calcareous tubeworms of the Phanerozoic"
7826:
7820:
7178:
7099:
6693:
6619:
6570:
6560:
6519:
6478:
6468:
6411:
6294:
6260:
6224:
6206:
6180:
6170:
5791:
4606:
2802:
1734:Coelom, locomotion and circulatory system
1511:. Some groups of annelids, including all
910:") around their bodies, which produces a
9256:
9180:Hemichordata (acorn worms and relatives)
9128:
8288:10.1146/annurev.ecolsys.35.112202.130124
8266:
7906:
7727:. Oxford University Press. p. 202.
7377:(7th ed.). Brooks / Cole. pp.
7343:(7th ed.). Brooks / Cole. pp.
7312:(7th ed.). Brooks / Cole. pp.
7278:(7th ed.). Brooks / Cole. pp.
7247:(7th ed.). Brooks / Cole. pp.
7216:(7th ed.). Brooks / Cole. pp.
7136:(7th ed.). Brooks / Cole. pp.
6912:(7th ed.). Brooks / Cole. pp.
6881:(7th ed.). Brooks / Cole. pp.
6850:(7th ed.). Brooks / Cole. pp.
6794:(7th ed.). Brooks / Cole. pp.
6763:(7th ed.). Brooks / Cole. pp.
6536:
6501:
6364:(7th ed.). Brooks / Cole. pp.
6073:(7th ed.). Brooks / Cole. pp.
5843:
5817:
5220:Phylogenetic tree of early lophophorates
5215:
3717:of the Annelid phylum is comprised by a
2543:
2052:
1934:
1930:
1818:
1352:
1327:
1304:
1301:
1282:
1276:
1268:
1248:
1225:
1159:' cuticles are made of the more rigid α-
10153:
8981:
8849:
8706:Environment, Development, and Evolution
8699:
7046:
6979:
6326:(7th ed.). Brooks / Cole. p.
6097:
2528:
2236:However, the lifecycles of most living
2216:. Later they sink to the sea-floor and
2048:
1139:(outer covering) that does not contain
984:, Siboglinidae, within the polychaetes.
747:, annelids serve humans as food and as
14:
11171:
10381:
9174:Echinodermata (starfish and relatives)
9144:Xenacoelomorpha (acoels and relatives)
8497:
8200:
7794:
7748:Briggs, D. E. G.; Kear, A. J. (1993).
7590:Edwards, C. A.; Bohlen, P. J. (1996).
7081:
6936:
6442:
2463:for the medically dubious practice of
2157:
2112:
1780:of vertebrates: producing and storing
1776:that perform similar functions to the
1518:The phylum's name is derived from the
1435:
1425:
1415:
10900:
10899:
10109:
9115:
8823:
7722:
7669:"The humble worm – with a difference"
7627:
7557:Nancarrow, L.; Taylor, J. H. (1998).
7503:"Towards a tree of life for Annelida"
7460:
6600:Communicative and Integrative Biology
5813:
5811:
4655:(fan-like feeding structures) and/or
3787:, are more difficult to place due to
3437:some "Scolecida" and "Canalipalpata"
2152:
2137:
1399:
1389:
1379:
11107:cf4d99f5-4ed6-4286-91d3-415c155cd975
11032:cc06e815-f413-4dd7-ab31-0281d34b845b
9445:Acanthocephala (thorny-headed worms)
8042:Australian Journal of Earth Sciences
7873:
7666:
6721:Cellular and Molecular Life Sciences
3662:Also in 1997 Damhnait McHugh, using
2162:
2147:
2142:
1750:. Each septum forms a sandwich with
1322:Two coelomata, main and in tentacles
573:, "little ring"), also known as the
8391:Organisms Diversity & Evolution
7529:
7088:Integrative and Comparative Biology
6400:Integrative and Comparative Biology
6213:Integrative and Comparative Biology
5837:
2205:. The fertilized eggs develop into
2132:
2127:
1171:Summary of distinguishing features
920:("with few hairs"), which includes
24:
9479:
9285:
9042:Cnidaria (jellyfish and relatives)
8314:from the original on 15 April 2009
8269:"The new view of animal phylogeny"
8171:from the original on 12 April 2009
8133:10.1111/j.1463-6409.1997.tb00412.x
8083:Canadian Journal of Earth Sciences
7965:Estonian Journal of Earth Sciences
7927:10.1111/j.1469-185X.1999.tb00046.x
7809:from the original on 27 March 2009
7018:from the original on 20 March 2009
6502:Hausdorf, B.; et al. (2007).
5808:
4651:and several other phyla that have
1638:(throat), consisting of a pair of
1533:
1341:Open outflow, return via branched
25:
11200:
11189:Extant Cambrian first appearances
8789:
7596:Biology and ecology of earthworms
7563:. Ten Speed Press. pp. 2–6.
3743:clade. This grade is followed by
3197:some "Scolecida" and "Aciculata"
1971:use "crowns" of palps covered in
1634:generally forms a ring round the
1465:Diagram of segments of an annelid
10086:Phyla with ≥1000 extant species
8807:
8795:
8443:10.1111/j.1096-3642.2008.00408.x
7892:10.1111/j.1463-6409.2004.00136.x
7592:"Earthworm ecology: communities"
7001:10.1046/j.1463-6409.2003.00122.x
6951:10.1111/j.1525-142X.2005.05039.x
5109:
5071:
5051:
5011:
4990:
4939:
4895:
4854:
4833:
4795:
4764:
3721:of basal groups of polychaetes:
2539:
2494:compounds and several important
2120:
2028:Annelids with blood vessels use
1746:and from each other by vertical
1530:Body wall, chaetae and parapodia
1372:
863:
529:
491:
134:
43:
8693:
8634:
8583:
8532:
8450:
8417:
8382:
8325:
8308:"Reading trees: A quick review"
8182:
7788:
7689:
7660:
7583:
7550:
7523:
7420:
7395:
7154:
7075:
7040:
7029:
6930:
6712:
6647:
6636:
6587:
6508:Molecular Biology and Evolution
6436:
6091:
5646:
3575:, previously phylum Pogonophora
2827:, whose best-known members are
2731:The earliest good evidence for
2568:tubes that some secreted. Some
2342:, and for mammals ranging from
1911:is via the skin. However, many
1542:Annelids' cuticles are made of
1364:
636:(which include earthworms) and
9273:Nematomorpha (horsehair worms)
8006:. CRC LEME. pp. 211–215.
7675:. Read Books. pp. 14–15.
7598:. Springer. pp. 124–126.
6980:Nielsen, C. (September 2003).
6596:"Sipunculans and segmentation"
5867:
5759:
5629:
5232:. Because of the body plan of
3481:, previously a separate phylum
3248:, previously a separate phylum
2287:("sperm stores") and then the
1898:
1833:moves this "worm" to the right
1359:
1243:Repetition of internal organs
13:
1:
9116:
8747:(21): S0960–9822(22)01455–5.
8708:. MIT Press. pp. 67–69.
8500:Handbook of Zoology: Annelida
7956:Vinn, O.; Mutvei, H. (2009).
7673:Practical Fresh Water Fishing
7036:The Invertebrate Tree of Life
5941:Encyclopedia of Life Sciences
5733:Acta Palaeontologica Polonica
5702:
2602:(i.e. in the phylum to which
2498:, one of which also prevents
1738:Most annelids have a pair of
1182:Recently merged into Annelida
960:, were treated as a separate
9885:Echinozoans inc. sea urchins
8165:The Tree of Life Web Project
7827:Vinn, O.; Zatoń, M. (2012).
5819:McIntosh, William Carmichael
5263:compartments; and a similar
4611:Annelids are members of the
1946:bacteria living inside them.
1903:In some annelids, including
1349:
1346:
1337:
1279:
1265:
1257:
1251:
1245:
1237:
1222:
1191:
1174:
1123:, although sharing a common
1099:as their closest relatives.
848:that function as limbs, and
816:Classification and diversity
7:
9942:Chelicerates inc. arachnids
9682:Phoronida (horseshoe worms)
9497:Platyhelminthes (flatworms)
9408:Gnathostomulida (jaw worms)
9297:Loricifera (corset animals)
7507:Assembling the tree of life
7053:, Oxford University Press,
6939:Evolution & Development
4623:animals – the other is the
2765:consisting of a convoluted
2325:. The burrowers loosen the
2295:that collects ova from the
2044:Reproduction and life cycle
1316:Two coelomata, main and in
10:
11205:
11184:Cambrian first appearances
9832:Medusozoans inc. jellyfish
9578:Annelida (segmented worms)
9403:Chaetognatha (arrow worms)
9319:Onychophora (velvet worms)
8463:Turkish Journal of Zoology
5827:. In Baynes, T. S. (ed.).
2560:, their fossils are rare.
2532:
1312:
1273:
1262:
1242:
1219:
687:that many species use for
624:organisms. They also have
581:, with over 22,000 extant
10908:
10871:
10689:
10606:
10558:
10443:
10434:
10377:
10149:
10145:
10140:phyla/divisions by domain
10082:
9880:Asterozoans inc. starfish
9782:
9775:
9726:
9677:Brachiopoda (lamp shells)
9667:
9658:Ectoprocta (moss animals)
9642:
9633:
9618:
9609:
9594:
9587:
9563:
9552:
9511:
9503:Gastrotricha (hairybacks)
9486:
9475:
9464:
9416:
9398:
9385:
9374:
9327:
9314:
9305:
9292:
9281:
9249:
9232:Kinorhyncha (mud dragons)
9218:
9207:
9192:
9168:
9159:
9139:
9124:
9111:
9076:
9051:
9027:
9012:
9004:Ctenophora (comb jellies)
8992:
8977:
8861:
8762:10.1016/j.cub.2022.09.011
8508:10.1515/9783110291582-002
8403:10.1007/s13127-016-0265-7
8359:10.1016/j.cub.2015.06.007
8062:10.1080/08120099708728303
7774:10.1017/S0094837300012343
7180:10.1016/j.cub.2024.02.055
6098:Lavelle, P. (July 1996).
5943:. John Wiley & Sons.
5793:10.1016/j.cub.2022.10.051
5635:The term originated from
5561:
5541:
5517:
5502:
5495:
5488:
5468:
5461:
5432:
5412:
5405:
5398:
5363:
5343:
5336:
5316:
5309:
5302:
5285:
5278:
5104:
5066:
5046:
5039:
5005:
4985:
4978:
4968:
4958:
4933:
4926:
4911:
4889:
4882:
4848:
4828:
4821:
4814:
4789:
4782:
4754:
4747:
4720:
4713:
4689:
4682:
4498:
4474:
4459:
4452:
4445:
4412:
4397:
4390:
4372:
4365:
4358:
4325:
4310:
4303:
4278:
4263:
4256:
4249:
4242:
4227:
4220:
4202:
4166:
4151:
4144:
4117:
4102:
4095:
4085:
4075:
4065:
4032:
4015:
4008:
3993:
3986:
3979:
3937:
3922:
3915:
3898:
3891:
3881:
3874:
3841:
3826:
3819:
3809:
3802:
3706:in the classification of
3627:
3587:
3569:
3562:
3549:
3542:
3502:
3475:
3462:
3455:
3448:
3435:
3402:
3378:
3345:
3323:
3316:
3297:
3290:
3283:
3269:
3242:
3229:
3222:
3215:
3208:
3195:
3188:
3181:
3174:
3110:
3068:
3035:
3020:
3013:
2986:
2971:
2956:
2949:
2939:
2929:
2902:
2887:
2880:
2873:
2855:
2848:
2769:partly filled with small
2271:(the group that includes
2201:into the water via their
1626:Nervous system and senses
1187:
1181:
1178:
1175:
1051:, mostly on the basis of
822:giant Gippsland earthworm
241:
236:
131:Scientific classification
129:
124:
115:
34:
27:Phylum of segmented worms
9438:Rotifera (wheel animals)
9237:Priapulida (penis worms)
8167:. Tree of Life Project.
8033:Retallack, G.J. (1997).
8002:. In Roach, I.C. (ed.).
7995:Humphreys, G.S. (2003).
6562:10.1186/1471-2164-10-136
6443:McHugh, D. (July 1997).
6151:BMC Evolutionary Biology
5983:. VermEcology, Yokohama.
5979:Blakemore, R.J. (2012).
5845:Mitchell, Peter Chalmers
5622:
2535:List of Annelid families
1526:, meaning "little ring".
1325:Coelom only in proboscis
1067:and Annelida (including
10350:Thermodesulfobacteriota
9652:Entoprocta or Kamptozoa
9624:Nemertea (ribbon worms)
9345:Tardigrada (waterbears)
9338:Arthropoda (arthropods)
8702:"The Determined Embryo"
8267:Halanych, K.M. (2004).
8228:10.1073/pnas.94.15.8006
7977:10.3176/earth.2009.4.07
7646:10.1023/A:1015681605656
6470:10.1073/pnas.94.15.8006
5981:Cosmopolitan Earthworms
5949:10.1038/npg.els.0001599
5903:10.1126/science.1230492
5860:Encyclopædia Britannica
5830:Encyclopædia Britannica
4615:, one of the two major
3664:molecular phylogenetics
2744: million years ago
2712: million years ago
2697: million years ago
2650:and John Peel reported
2631: million years ago
2550:Burgessochaeta setigera
2459:Accounts of the use of
2413:Interaction with humans
2386:Although blood-sucking
2304:Ecological significance
1865:in some species, green
1291:Generally no; but some
1263:Septa between segments
1103:Distinguishing features
998:molecular phylogenetics
852:that are thought to be
791: million years ago
776: million years ago
610:bilaterally symmetrical
237:Classes and subclasses
41:Cambrian Stage 3–recent
9827:Anthozoans inc. corals
9526:Dicyemida or Rhombozoa
8700:Pearson, R.D. (2003).
8668:10.1073/pnas.97.9.4434
7795:Miller, A. J. (2004).
7082:Jenner, R. A. (2006).
6207:Hutchings, P. (2007).
6172:10.1186/1471-2148-7-57
5724:; Pjeel, J.S. (2008).
5221:
4635:under the super-group
4607:External relationships
3659:
2803:Internal relationships
2788:going back to the mid
2578:in some ways resemble
2553:
2521:that bind strongly to
2421:. The rear end of the
2242:external fertilization
2065:
1947:
1837:Many annelids move by
1834:
1652:central nervous system
1539:
1338:Closed in most species
1220:External segmentation
1188:Similar-looking phyla
739:by enabling water and
660:, a "super-phylum" of
568:
11128:Paleobiology Database
10578:Neocallimastigomycota
9957:Hexapods inc. insects
9267:Nematoda (roundworms)
7835:(CG2012_A03): 39–47.
6521:10.1093/molbev/msm214
6107:Biology International
5745:10.4202/app.2008.0110
5637:Jean-Baptiste Lamarck
5238:phylogenetic analysis
5219:
4659:larvae as members of
3589:some "Canalipalpata"
3551:some "Canalipalpata"
3231:some "Canalipalpata"
3163:
2622:, both from Canada's
2547:
2056:
1938:
1931:Feeding and excretion
1829:
1718:evolved independently
1537:
1295:molt their jaws, and
1229:Only in a few species
632:(almost all marine),
11027:Fauna Europaea (new)
10243:Coprothermobacterota
9150:Chordata (chordates)
8804:at Wikimedia Commons
8004:Advances in Regolith
7725:Invertebrate Zoology
7667:Sell, F. E. (2008).
7630:Hediste diversicolor
7463:Invertebrate Zoology
7429:Invertebrate Zoology
7374:Invertebrate Zoology
7340:Invertebrate Zoology
7309:Invertebrate Zoology
7275:Invertebrate Zoology
7244:Invertebrate Zoology
7213:Invertebrate Zoology
7133:Invertebrate Zoology
6909:Invertebrate Zoology
6878:Invertebrate Zoology
6847:Invertebrate Zoology
6821:Invertebrate Zoology
6791:Invertebrate Zoology
6760:Invertebrate Zoology
6696:Invertebrate Zoology
6612:10.4161/cib.2.1.7505
6413:10.1093/icb/42.3.678
6361:Invertebrate Zoology
6323:Invertebrate Zoology
6297:Invertebrate Zoology
6263:Invertebrate Zoology
6070:Invertebrate Zoology
5778:(24): 5382–5389.e3.
5722:Conway Morris, Simon
2795:472 to 461
2780:251 to 245
2739:period, which began
2684:488 to 474
2594:549 to 542
2529:Evolutionary history
2049:Asexual reproduction
1804:waste products into
1155:– on the other hand
934:, whose name means "
827:Amynthas mekongianus
804:472 to 461
9600:Mollusca (molluscs)
9085:of the animal root
8753:2022CBio...32E4769G
8659:2000PNAS...97.4434S
8604:1997Natur.387R.489A
8561:10.1038/nature06614
8553:2008Natur.452..745D
8476:10.3906/zoo-1002-27
8350:2015CBio...25.1993S
8219:1997PNAS...94.8006M
8201:McHugh, D. (1997).
8095:1982CaJES..19.2150M
8054:1997AuJES..44..185R
7833:Carnets de Géologie
7766:1993Pbio...19..107B
7530:New, T. R. (2005).
6461:1997PNAS...94.8006M
6163:2007BMCEE...7...57S
5895:2013Sci...339..684R
5784:2022CBio...32E5382B
5676:10.1038/nature09864
5668:2011Natur.471...95S
2757:130 to 90
2648:Simon Conway Morris
2584:small shelly fossil
2556:Since annelids are
2129:Apical tuft (cilia)
2113:Sexual reproduction
1859:respiratory pigment
1559:, which is made of
1335:Circulatory system
1172:
1091:are annelids, with
759:Since annelids are
664:that also includes
10573:Blastocladiomycota
9813:Calcareous sponges
8998:Porifera (sponges)
7841:10.4267/2042/46095
7101:10.1093/icb/icj014
6733:10.1007/BF01953812
6226:10.1093/icb/icm008
5222:
3381:some "Oligochaeta"
3348:some "Oligochaeta"
2554:
2471:Hirudo medicinalis
2134:Prototroch (cilia)
2066:
2015:hydrothermal vents
1948:
1835:
1754:in the middle and
1660:segmental ganglion
1656:ventral nerve cord
1614:(fused bundles of
1590:and are formed by
1540:
1509:teloblastic growth
1255:In primitive forms
1170:
1129:circulatory system
833:Microchaetus rappi
603:hydrothermal vents
11166:
11165:
11115:Open Tree of Life
10902:Taxon identifiers
10893:
10892:
10889:
10888:
10867:
10866:
10430:
10429:
10373:
10372:
10365:Verrucomicrobiota
10103:
10102:
10078:
10077:
9771:
9770:
9767:
9766:
9722:
9721:
9718:
9717:
9714:
9713:
9710:
9709:
9706:
9705:
9702:
9701:
9698:
9697:
9694:
9693:
9690:
9689:
9548:
9547:
9544:
9543:
9460:
9459:
9456:
9455:
9370:
9369:
9366:
9365:
9362:
9361:
9358:
9357:
9354:
9353:
9245:
9244:
9188:
9187:
9107:
9106:
9072:
9071:
9068:
9067:
8800:Media related to
8715:978-0-262-08319-5
8598:(6632): 489–493.
8547:(7188): 745–749.
8344:(15): 1993–1999.
8213:(15): 8006–8009.
8121:Zoologica Scripta
8089:(11): 2150–2157.
8013:978-0-7315-5221-4
7880:Zoologica Scripta
7734:978-0-19-551368-4
7682:978-1-4437-6157-4
7605:978-0-412-56160-3
7570:978-0-89815-994-3
7543:978-0-521-53201-3
7516:978-0-19-517234-8
7472:978-0-19-551368-4
7413:978-0-07-252844-2
7388:978-0-03-025982-1
7354:978-0-03-025982-1
7323:978-0-03-025982-1
7289:978-0-03-025982-1
7258:978-0-03-025982-1
7227:978-0-03-025982-1
7147:978-0-03-025982-1
7060:978-0-19-856620-5
6989:Zoologica Scripta
6923:978-0-03-025982-1
6892:978-0-03-025982-1
6861:978-0-03-025982-1
6830:978-0-19-551368-4
6805:978-0-03-025982-1
6774:978-0-03-025982-1
6705:978-0-19-551368-4
6514:(12): 2723–2729.
6455:(15): 8006–8009.
6375:978-0-03-025982-1
6337:978-0-03-025982-1
6306:978-0-19-551368-4
6272:978-0-19-551368-4
6084:978-0-03-025982-1
5889:(6120): 684–687.
5619:
5618:
5610:
5609:
5601:
5600:
5592:
5591:
5583:
5582:
5574:
5573:
5530:
5529:
5445:
5444:
5387:
5386:
5378:
5377:
5194:
5193:
5185:
5184:
5176:
5175:
5167:
5166:
5158:
5157:
5149:
5148:
5140:
5139:
5131:
5130:
5122:
5121:
5093:
5092:
5084:
5083:
5036:Bryozoa s.l.
5025:
5024:
4868:
4867:
4627:, which includes
4603:
4602:
4594:
4593:
4585:
4584:
4576:
4575:
4567:
4566:
4558:
4557:
4549:
4548:
4540:
4539:
4531:
4530:
4522:
4521:
4487:
4486:
4434:
4433:
4425:
4424:
4347:
4346:
4338:
4337:
4292:
4291:
4188:
4187:
4179:
4178:
4130:
4129:
4054:
4053:
4045:
4044:
3968:
3967:
3959:
3958:
3950:
3949:
3888:Chaetopteriformia
3863:
3862:
3854:
3853:
3727:Chaetopteriformia
3715:phylogenetic tree
3647:
3646:
3638:
3637:
3616:
3615:
3607:
3606:
3598:
3597:
3531:
3530:
3522:
3521:
3513:
3512:
3504:some "Scolecida"
3491:
3490:
3464:some "Scolecida"
3424:
3423:
3415:
3414:
3391:
3390:
3367:
3366:
3358:
3357:
3258:
3257:
3133:
3132:
3123:
3122:
3099:
3098:
3090:
3089:
3081:
3080:
3057:
3056:
3048:
3047:
2999:
2998:
2915:
2914:
2797:million years ago
2782:million years ago
2759:million years ago
2686:million years ago
2665:million years old
2596:million years ago
2492:anti-inflammatory
2357:Amynthas agrestis
2193:, which released
2184:Trochophore larva
2149:Metatroch (cilia)
2005:matter – such as
1827:
1774:chloragogen cells
1765:epitheliomuscular
1752:connective tissue
1561:connective tissue
1421: Growth zone
1395: Peristomium
1357:
1356:
1299:molt their skins
1274:Cuticle material
991:have a checkered
926:organic materials
806:million years ago
608:The Annelids are
484:
483:
257:Chaetopteriformia
232:
16:(Redirected from
11196:
11159:
11158:
11146:
11145:
11136:
11135:
11123:
11122:
11110:
11109:
11100:
11099:
11087:
11086:
11074:
11073:
11061:
11060:
11048:
11047:
11035:
11034:
11022:
11021:
11009:
11008:
10996:
10995:
10983:
10982:
10970:
10969:
10957:
10956:
10944:
10943:
10942:
10929:
10928:
10927:
10897:
10896:
10641:Anthocerotophyta
10520:Hemimastigophora
10441:
10440:
10412:Nitrososphaerota
10379:
10378:
10355:Thermomicrobiota
10295:Kiritimatiellota
10290:Ignavibacteriota
10255:Deferribacterota
10218:Campylobacterota
10203:Bdellovibrionota
10151:
10150:
10147:
10146:
10130:
10123:
10116:
10107:
10106:
9784:
9783:
9740:
9640:
9639:
9616:
9615:
9592:
9591:
9561:
9560:
9557:
9484:
9483:
9477:
9476:
9473:
9472:
9469:
9396:
9395:
9387:
9386:
9383:
9382:
9379:
9312:
9311:
9290:
9289:
9283:
9282:
9254:
9253:
9220:
9219:
9216:
9215:
9212:
9205:
9204:
9201:
9194:
9193:
9166:
9165:
9137:
9136:
9133:
9126:
9125:
9113:
9112:
9090:
9025:
9024:
8990:
8989:
8986:
8979:
8978:
8890:
8870:
8844:
8837:
8830:
8821:
8820:
8812:Data related to
8811:
8799:
8783:
8782:
8764:
8732:
8726:
8725:
8723:
8722:
8697:
8691:
8690:
8680:
8670:
8653:(9): 4434–4437.
8638:
8632:
8631:
8612:10.1038/387489a0
8587:
8581:
8580:
8536:
8530:
8529:
8495:
8489:
8488:
8478:
8454:
8448:
8447:
8445:
8421:
8415:
8414:
8386:
8380:
8379:
8361:
8329:
8323:
8322:
8320:
8319:
8304:
8298:
8297:
8295:
8294:
8273:
8264:
8251:
8250:
8240:
8230:
8198:
8189:
8186:
8180:
8179:
8177:
8176:
8156:
8145:
8144:
8116:
8107:
8106:
8078:
8072:
8071:
8069:
8068:
8039:
8030:
8024:
8023:
8021:
8020:
8001:
7992:
7981:
7980:
7962:
7953:
7947:
7946:
7910:
7904:
7903:
7871:
7856:
7855:
7853:
7852:
7843:. Archived from
7824:
7818:
7817:
7815:
7814:
7808:
7801:
7792:
7786:
7785:
7745:
7739:
7738:
7720:
7714:
7713:
7711:
7710:
7697:"Rags to riches"
7693:
7687:
7686:
7664:
7658:
7657:
7640:(1–3): 203–218.
7625:
7616:
7615:
7613:
7612:
7587:
7581:
7580:
7578:
7577:
7554:
7548:
7547:
7527:
7521:
7520:
7498:
7477:
7476:
7458:
7443:
7442:
7424:
7418:
7417:
7404:Animal Diversity
7399:
7393:
7392:
7368:
7359:
7358:
7334:
7328:
7327:
7303:
7294:
7293:
7269:
7263:
7262:
7238:
7232:
7231:
7207:
7201:
7200:
7182:
7173:(7): R269–R270.
7158:
7152:
7151:
7127:
7114:
7113:
7103:
7079:
7073:
7072:
7044:
7038:
7033:
7027:
7026:
7024:
7023:
7017:
6986:
6977:
6971:
6970:
6934:
6928:
6927:
6903:
6897:
6896:
6872:
6866:
6865:
6841:
6835:
6834:
6816:
6810:
6809:
6785:
6779:
6778:
6754:
6745:
6744:
6716:
6710:
6709:
6691:
6656:
6651:
6645:
6640:
6634:
6633:
6623:
6591:
6585:
6584:
6574:
6564:
6540:
6534:
6533:
6523:
6499:
6493:
6492:
6482:
6472:
6440:
6434:
6433:
6415:
6391:
6380:
6379:
6355:
6342:
6341:
6317:
6311:
6310:
6292:
6277:
6276:
6258:
6231:
6230:
6228:
6204:
6195:
6194:
6184:
6174:
6142:
6121:
6120:
6118:
6117:
6104:
6095:
6089:
6088:
6064:
5985:
5984:
5976:
5963:
5962:
5936:
5923:
5922:
5880:
5871:
5865:
5864:
5852:
5850:"Annelida"
5841:
5835:
5834:
5826:
5824:"Annelida"
5815:
5806:
5805:
5795:
5763:
5757:
5756:
5730:
5718:
5696:
5695:
5650:
5644:
5633:
5545:
5498:
5497:
5491:
5490:
5472:
5464:
5463:
5416:
5408:
5407:
5401:
5400:
5347:
5339:
5338:
5320:
5312:
5311:
5305:
5304:
5281:
5280:
5271:
5270:
5113:
5075:
5055:
5042:
5041:
5016:
5015:
4994:
4981:
4980:
4971:
4970:
4961:
4960:
4944:
4943:
4929:
4928:
4900:
4899:
4885:
4884:
4859:
4858:
4837:
4824:
4823:
4817:
4816:
4800:
4799:
4785:
4784:
4768:
4750:
4749:
4716:
4715:
4700:Nemertodermatida
4685:
4684:
4675:
4674:
4513:
4455:
4454:
4448:
4447:
4393:
4392:
4368:
4367:
4361:
4360:
4306:
4305:
4283:(pogonophorans)
4259:
4258:
4252:
4251:
4245:
4244:
4223:
4222:
4147:
4146:
4141:Protodriliformia
4098:
4097:
4088:
4087:
4078:
4077:
4068:
4067:
4011:
4010:
3989:
3988:
3982:
3981:
3918:
3917:
3894:
3893:
3884:
3883:
3877:
3876:
3822:
3821:
3812:
3811:
3805:
3804:
3795:
3794:
3576:
3565:
3564:
3545:
3544:
3482:
3458:
3457:
3451:
3450:
3382:
3349:
3334:
3319:
3318:
3305:
3293:
3292:
3286:
3285:
3280:
3272:
3271:
3249:
3225:
3224:
3218:
3217:
3211:
3210:
3191:
3190:
3184:
3183:
3177:
3176:
3167:
3166:
3016:
3015:
2952:
2951:
2942:
2941:
2932:
2931:
2883:
2882:
2876:
2875:
2851:
2850:
2844:
2843:
2839:
2838:
2819:, which include
2798:
2783:
2760:
2748:flowering plants
2745:
2720:British Columbia
2713:
2698:
2687:
2666:
2632:
2597:
2572:fossils such as
2407:whirling disease
2381:aerobic bacteria
2212:, which live as
2176:
2168:
2166:
2160:
2155:
2150:
2145:
2140:
2135:
2130:
2124:
2007:hydrogen sulfide
1944:chemoautotrophic
1828:
1796:; breaking down
1788:; producing the
1602:("bristles") of
1457:
1449:
1448:
1446:
1445:
1444:
1433:
1432:
1430:
1423:
1422:
1420:
1413:
1412:
1410:
1409:
1408:
1397:
1396:
1394:
1387:
1386:
1385: Prostomium
1384:
1376:
1173:
1169:
874:
867:
807:
792:
777:
571:
561:
560:
557:
556:
553:
550:
547:
544:
541:
538:
535:
523:
522:
519:
518:
515:
512:
509:
506:
503:
500:
497:
472:
464:
456:
448:
428:Branchiobdellida
424:
404:
389:
387:Traditional view
294:Protodriliformia
247:
227:
139:
138:
120:
105:
42:
38:Temporal range:
32:
31:
21:
11204:
11203:
11199:
11198:
11197:
11195:
11194:
11193:
11169:
11168:
11167:
11162:
11154:
11149:
11141:
11139:
11131:
11126:
11118:
11113:
11105:
11103:
11095:
11090:
11082:
11077:
11069:
11064:
11056:
11051:
11043:
11038:
11030:
11025:
11017:
11012:
11004:
10999:
10991:
10986:
10978:
10973:
10965:
10960:
10952:
10947:
10938:
10937:
10932:
10923:
10922:
10917:
10904:
10894:
10885:
10863:
10814:Gnathostomulida
10719:Xenacoelomorpha
10685:
10681:Flowering plant
10636:Marchantiophyta
10602:
10568:Chytridiomycota
10554:
10426:
10369:
10325:Planctomycetota
10285:Gemmatimonadota
10270:Elusimicrobiota
10163:Acidobacteriota
10141:
10134:
10104:
10099:
10074:
10000:Phylactolaemata
9788:
9778:
9777:
9763:
9754:Xenambulacraria
9730:
9686:
9663:
9629:
9611:Kryptotrochozoa
9605:
9583:
9553:
9540:
9531:Monoblastozoa (
9507:
9465:
9452:
9424:Micrognathozoa
9412:
9375:
9350:
9323:
9301:
9277:
9241:
9208:
9197:
9184:
9155:
9129:
9120:
9103:
9080:
9064:
9047:
9016:
9008:
8982:
8973:
8972:
8888:
8866:
8857:
8848:
8792:
8787:
8786:
8741:Current Biology
8733:
8729:
8720:
8718:
8716:
8698:
8694:
8639:
8635:
8588:
8584:
8537:
8533:
8518:
8496:
8492:
8455:
8451:
8422:
8418:
8387:
8383:
8338:Current Biology
8330:
8326:
8317:
8315:
8306:
8305:
8301:
8292:
8290:
8271:
8265:
8254:
8199:
8192:
8187:
8183:
8174:
8172:
8157:
8148:
8117:
8110:
8103:10.1139/e82-189
8079:
8075:
8066:
8064:
8037:
8031:
8027:
8018:
8016:
8014:
7999:
7993:
7984:
7960:
7954:
7950:
7911:
7907:
7872:
7859:
7850:
7848:
7825:
7821:
7812:
7810:
7806:
7799:
7793:
7789:
7746:
7742:
7735:
7721:
7717:
7708:
7706:
7695:
7694:
7690:
7683:
7665:
7661:
7626:
7619:
7610:
7608:
7606:
7588:
7584:
7575:
7573:
7571:
7555:
7551:
7544:
7528:
7524:
7517:
7499:
7480:
7473:
7459:
7446:
7439:
7425:
7421:
7414:
7400:
7396:
7389:
7369:
7362:
7355:
7335:
7331:
7324:
7304:
7297:
7290:
7270:
7266:
7259:
7239:
7235:
7228:
7208:
7204:
7167:Current Biology
7159:
7155:
7148:
7128:
7117:
7080:
7076:
7061:
7045:
7041:
7034:
7030:
7021:
7019:
7015:
6984:
6978:
6974:
6935:
6931:
6924:
6904:
6900:
6893:
6873:
6869:
6862:
6842:
6838:
6831:
6817:
6813:
6806:
6786:
6782:
6775:
6755:
6748:
6717:
6713:
6706:
6692:
6659:
6652:
6648:
6641:
6637:
6592:
6588:
6541:
6537:
6500:
6496:
6441:
6437:
6392:
6383:
6376:
6356:
6345:
6338:
6318:
6314:
6307:
6293:
6280:
6273:
6259:
6234:
6205:
6198:
6143:
6124:
6115:
6113:
6102:
6096:
6092:
6085:
6065:
5988:
5977:
5966:
5959:
5937:
5926:
5878:
5872:
5868:
5842:
5838:
5816:
5809:
5772:Current Biology
5764:
5760:
5728:
5719:
5710:
5705:
5700:
5699:
5662:(7336): 95–98.
5651:
5647:
5634:
5630:
5625:
5620:
5611:
5602:
5593:
5584:
5575:
5531:
5446:
5388:
5379:
5234:lophotrochozoan
5195:
5186:
5177:
5168:
5159:
5150:
5141:
5132:
5123:
5094:
5085:
5026:
5010:
4955:Kryptotrochozoa
4938:
4894:
4869:
4853:
4794:
4667:("animals that
4609:
4604:
4595:
4586:
4577:
4568:
4559:
4550:
4541:
4532:
4523:
4500:
4488:
4462:Terebelliformia
4435:
4426:
4348:
4339:
4293:
4266:Cirratuliformia
4189:
4180:
4131:
4072:Pleistoannelida
4055:
4046:
3969:
3960:
3951:
3864:
3855:
3745:Pleistoannelida
3660:
3656:
3649:
3648:
3639:
3617:
3608:
3599:
3571:
3532:
3523:
3514:
3492:
3477:
3425:
3416:
3392:
3380:
3368:
3359:
3347:
3325:
3299:
3281:
3276:
3259:
3244:
3124:
3100:
3091:
3082:
3058:
3049:
3000:
2916:
2805:
2793:
2778:
2755:
2740:
2708:
2693:
2682:
2661:
2627:
2626:, formed about
2592:
2542:
2537:
2531:
2415:
2306:
2187:
2186:
2185:
2183:
2178:
2177:
2170:
2169:
2164:
2163:
2161:
2158:
2156:
2153:
2151:
2148:
2146:
2143:
2141:
2138:
2136:
2133:
2131:
2128:
2125:
2115:
2051:
2046:
1940:Lamellibrachian
1933:
1901:
1819:
1736:
1628:
1532:
1468:
1467:
1466:
1464:
1459:
1458:
1451:
1450:
1440:
1439:
1438:
1437:
1436:
1434:
1428:
1427:
1426:
1424:
1418:
1417:
1416:
1414:
1404:
1403:
1402:
1401:
1400:
1398:
1392:
1391:
1390:
1388:
1382:
1381:
1380:
1377:
1367:
1362:
1266:In most species
1232:Yes, except in
1185:Closely related
1105:
1035:acanthocephales
958:marine sediment
892:
891:
890:
881:
876:
875:
868:
818:
802:
787:
772:
640:-like species.
575:segmented worms
532:
528:
494:
490:
470:
462:
454:
446:
418:
398:
385:
383:
365:Terebelliformia
328:Cirratuliformia
279:Pleistoannelida
243:
226:
133:
111:
110:record, 567 Ma
104:
103:
98:
93:
88:
83:
78:
73:
68:
63:
58:
53:
48:
40:
39:
36:
28:
23:
22:
15:
12:
11:
5:
11202:
11192:
11191:
11186:
11181:
11164:
11163:
11161:
11160:
11147:
11137:
11124:
11111:
11101:
11088:
11075:
11062:
11049:
11036:
11023:
11014:Fauna Europaea
11010:
10997:
10984:
10971:
10958:
10945:
10930:
10914:
10912:
10906:
10905:
10891:
10890:
10887:
10886:
10879:
10877:
10874:Incertae sedis
10869:
10868:
10865:
10864:
10862:
10861:
10856:
10851:
10846:
10841:
10836:
10831:
10826:
10821:
10819:Micrognathozoa
10816:
10811:
10809:Acanthocephala
10806:
10801:
10796:
10791:
10786:
10781:
10776:
10771:
10766:
10761:
10756:
10751:
10746:
10741:
10736:
10731:
10726:
10721:
10716:
10711:
10706:
10701:
10695:
10693:
10687:
10686:
10684:
10683:
10678:
10673:
10668:
10663:
10658:
10653:
10651:Lycopodiophyta
10648:
10643:
10638:
10633:
10628:
10623:
10618:
10612:
10610:
10604:
10603:
10601:
10600:
10595:
10590:
10585:
10580:
10575:
10570:
10564:
10562:
10556:
10555:
10553:
10552:
10547:
10542:
10537:
10532:
10527:
10522:
10517:
10512:
10507:
10502:
10497:
10492:
10487:
10482:
10477:
10472:
10467:
10465:Ancyromonadida
10462:
10457:
10451:
10449:
10438:
10432:
10431:
10428:
10427:
10425:
10424:
10419:
10417:Thermoproteota
10414:
10409:
10402:
10395:
10387:
10385:
10375:
10374:
10371:
10370:
10368:
10367:
10362:
10357:
10352:
10347:
10342:
10337:
10332:
10330:Pseudomonadota
10327:
10322:
10317:
10312:
10307:
10305:Mycoplasmatota
10302:
10300:Lentisphaerota
10297:
10292:
10287:
10282:
10280:Fusobacteriota
10277:
10275:Fibrobacterota
10272:
10267:
10262:
10257:
10252:
10245:
10240:
10235:
10230:
10225:
10220:
10215:
10210:
10205:
10200:
10195:
10190:
10185:
10180:
10178:Armatimonadota
10175:
10170:
10168:Actinomycetota
10165:
10159:
10157:
10143:
10142:
10133:
10132:
10125:
10118:
10110:
10101:
10100:
10098:
10097:
10090:
10083:
10080:
10079:
10076:
10075:
10073:
10072:
10071:
10070:
10065:
10060:
10055:
10050:
10038:
10037:
10036:
10031:
10026:
10014:
10013:
10012:
10007:
10002:
9990:
9989:
9988:
9983:
9978:
9973:
9965:Platyhelminths
9961:
9960:
9959:
9954:
9949:
9944:
9932:
9931:
9930:
9925:
9920:
9908:
9907:
9906:
9901:
9889:
9888:
9887:
9882:
9877:
9865:
9864:
9863:
9858:
9853:
9841:
9840:
9839:
9834:
9829:
9817:
9816:
9815:
9810:
9805:
9792:
9790:
9780:
9779:
9776:
9773:
9772:
9769:
9768:
9765:
9764:
9762:
9761:
9759:Centroneuralia
9756:
9751:
9746:
9741:
9727:
9724:
9723:
9720:
9719:
9716:
9715:
9712:
9711:
9708:
9707:
9704:
9703:
9700:
9699:
9696:
9695:
9692:
9691:
9688:
9687:
9685:
9684:
9679:
9673:
9671:
9665:
9664:
9662:
9661:
9654:
9648:
9646:
9637:
9631:
9630:
9628:
9627:
9619:
9613:
9607:
9606:
9604:
9603:
9595:
9589:
9585:
9584:
9582:
9581:
9574:
9564:
9558:
9555:Lophotrochozoa
9550:
9549:
9546:
9545:
9542:
9541:
9539:
9538:
9528:
9523:
9517:
9515:
9509:
9508:
9506:
9505:
9500:
9492:
9490:
9481:
9470:
9467:Platytrochozoa
9462:
9461:
9458:
9457:
9454:
9453:
9451:
9450:
9449:
9448:
9441:
9429:
9426:(Limnognathia)
9420:
9418:
9414:
9413:
9411:
9410:
9405:
9399:
9393:
9380:
9372:
9371:
9368:
9367:
9364:
9363:
9360:
9359:
9356:
9355:
9352:
9351:
9349:
9348:
9341:
9333:
9331:
9325:
9324:
9322:
9321:
9315:
9309:
9303:
9302:
9300:
9299:
9293:
9287:
9279:
9278:
9276:
9275:
9270:
9262:
9260:
9251:
9247:
9246:
9243:
9242:
9240:
9239:
9234:
9228:
9226:
9213:
9202:
9190:
9189:
9186:
9185:
9183:
9182:
9177:
9169:
9163:
9157:
9156:
9154:
9153:
9146:
9140:
9134:
9122:
9121:
9109:
9108:
9105:
9104:
9102:
9101:
9096:
9091:
9077:
9074:
9073:
9070:
9069:
9066:
9065:
9063:
9062:
9058:
9056:
9055:(Triploblasts)
9049:
9048:
9046:
9045:
9038:
9036:and relatives)
9028:
9022:
9010:
9009:
9007:
9006:
9001:
8993:
8987:
8975:
8974:
8971:
8970:
8969:
8968:
8967:
8966:
8963:Mesomycetozoea
8960:
8955:
8945:
8935:
8934:
8933:
8928:
8923:
8918:
8913:
8912:
8911:
8899:Diaphoretickes
8896:
8891:
8886:
8881:
8876:
8871:
8863:
8862:
8859:
8858:
8847:
8846:
8839:
8832:
8824:
8818:
8817:
8816:at Wikispecies
8805:
8791:
8790:External links
8788:
8785:
8784:
8727:
8714:
8692:
8633:
8582:
8531:
8516:
8490:
8449:
8416:
8397:(2): 345–362.
8381:
8324:
8299:
8252:
8190:
8181:
8146:
8127:(2): 139–204.
8108:
8073:
8048:(2): 185–201.
8025:
8012:
7982:
7971:(4): 286–296.
7948:
7905:
7857:
7819:
7787:
7760:(1): 107–135.
7740:
7733:
7715:
7688:
7681:
7659:
7617:
7604:
7582:
7569:
7549:
7542:
7522:
7515:
7478:
7471:
7444:
7437:
7419:
7412:
7394:
7387:
7360:
7353:
7329:
7322:
7295:
7288:
7264:
7257:
7233:
7226:
7202:
7153:
7146:
7115:
7074:
7063:, p. 82:
7059:
7039:
7028:
6995:(5): 475–482.
6972:
6945:(4): 337–340.
6929:
6922:
6898:
6891:
6867:
6860:
6836:
6829:
6811:
6804:
6780:
6773:
6746:
6711:
6704:
6657:
6646:
6635:
6586:
6535:
6494:
6435:
6406:(3): 678–684.
6381:
6374:
6343:
6336:
6312:
6305:
6278:
6271:
6232:
6219:(5): 788–789.
6196:
6122:
6090:
6083:
5986:
5964:
5958:978-0470016176
5957:
5924:
5866:
5855:Chisholm, Hugh
5836:
5807:
5758:
5739:(1): 137–148.
5707:
5706:
5704:
5701:
5698:
5697:
5645:
5627:
5626:
5624:
5621:
5617:
5616:
5613:
5612:
5608:
5607:
5604:
5603:
5599:
5598:
5595:
5594:
5590:
5589:
5586:
5585:
5581:
5580:
5577:
5576:
5572:
5571:
5568:
5567:
5560:
5557:
5556:
5553:
5552:
5540:
5537:
5536:
5533:
5532:
5528:
5527:
5524:
5523:
5516:
5513:
5512:
5509:
5508:
5501:
5496:
5494:
5489:
5487:
5484:
5483:
5480:
5479:
5467:
5462:
5460:
5452:
5451:
5448:
5447:
5443:
5442:
5439:
5438:
5431:
5428:
5427:
5424:
5423:
5411:
5406:
5404:
5399:
5397:
5394:
5393:
5390:
5389:
5385:
5384:
5381:
5380:
5376:
5375:
5372:
5371:
5362:
5359:
5358:
5355:
5354:
5342:
5337:
5335:
5332:
5331:
5328:
5327:
5315:
5310:
5308:
5303:
5301:
5298:
5297:
5294:
5293:
5284:
5279:
5277:
5275:Lophotrochozoa
5269:
5265:metanephridial
5192:
5191:
5188:
5187:
5183:
5182:
5179:
5178:
5174:
5173:
5170:
5169:
5165:
5164:
5161:
5160:
5156:
5155:
5152:
5151:
5147:
5146:
5143:
5142:
5138:
5137:
5134:
5133:
5129:
5128:
5125:
5124:
5120:
5119:
5116:
5115:
5103:
5100:
5099:
5096:
5095:
5091:
5090:
5087:
5086:
5082:
5081:
5078:
5077:
5065:
5062:
5061:
5058:
5057:
5045:
5040:
5038:
5032:
5031:
5028:
5027:
5023:
5022:
5019:
5018:
5004:
5001:
5000:
4997:
4996:
4984:
4979:
4977:
4969:
4967:
4959:
4957:
4951:
4950:
4947:
4946:
4932:
4927:
4925:
4922:
4921:
4918:
4917:
4910:
4907:
4906:
4903:
4902:
4888:
4883:
4881:
4879:Lophotrochozoa
4875:
4874:
4871:
4870:
4866:
4865:
4862:
4861:
4847:
4844:
4843:
4840:
4839:
4827:
4822:
4820:
4815:
4813:
4811:Platytrochozoa
4807:
4806:
4803:
4802:
4788:
4783:
4781:
4775:
4774:
4771:
4770:
4753:
4748:
4746:
4740:
4739:
4736:
4735:
4727:Ambulacrarians
4719:
4714:
4712:
4709:
4708:
4705:
4704:
4688:
4683:
4681:
4673:
4661:Lophotrochozoa
4608:
4605:
4601:
4600:
4597:
4596:
4592:
4591:
4588:
4587:
4583:
4582:
4579:
4578:
4574:
4573:
4570:
4569:
4565:
4564:
4561:
4560:
4556:
4555:
4552:
4551:
4547:
4546:
4543:
4542:
4538:
4537:
4534:
4533:
4529:
4528:
4525:
4524:
4520:
4519:
4516:
4515:
4497:
4494:
4493:
4490:
4489:
4485:
4484:
4481:
4480:
4473:
4470:
4469:
4466:
4465:
4458:
4453:
4451:
4446:
4444:
4441:
4440:
4437:
4436:
4432:
4431:
4428:
4427:
4423:
4422:
4419:
4418:
4411:
4408:
4407:
4404:
4403:
4396:
4391:
4389:
4383:
4382:
4379:
4378:
4371:
4366:
4364:
4359:
4357:
4354:
4353:
4350:
4349:
4345:
4344:
4341:
4340:
4336:
4335:
4332:
4331:
4324:
4321:
4320:
4317:
4316:
4309:
4304:
4302:
4299:
4298:
4295:
4294:
4290:
4289:
4286:
4285:
4277:
4274:
4273:
4270:
4269:
4262:
4257:
4255:
4250:
4248:
4243:
4241:
4238:
4237:
4234:
4233:
4226:
4221:
4219:
4213:
4212:
4209:
4208:
4201:
4195:
4194:
4191:
4190:
4186:
4185:
4182:
4181:
4177:
4176:
4173:
4172:
4165:
4162:
4161:
4158:
4157:
4150:
4145:
4143:
4137:
4136:
4133:
4132:
4128:
4127:
4124:
4123:
4116:
4113:
4112:
4109:
4108:
4101:
4096:
4094:
4086:
4084:
4076:
4074:
4066:
4064:
4061:
4060:
4057:
4056:
4052:
4051:
4048:
4047:
4043:
4042:
4039:
4038:
4031:
4028:
4027:
4024:
4023:
4019:Lobatocerebrum
4014:
4009:
4007:
4004:
4003:
4000:
3999:
3992:
3987:
3985:
3980:
3978:
3975:
3974:
3971:
3970:
3966:
3965:
3962:
3961:
3957:
3956:
3953:
3952:
3948:
3947:
3944:
3943:
3940:Chaetopteridae
3936:
3933:
3932:
3929:
3928:
3925:Psammodrilidae
3921:
3916:
3914:
3911:
3910:
3907:
3906:
3902:Apistobranchus
3897:
3892:
3890:
3882:
3880:
3875:
3873:
3870:
3869:
3866:
3865:
3861:
3860:
3857:
3856:
3852:
3851:
3848:
3847:
3840:
3837:
3836:
3833:
3832:
3825:
3820:
3818:
3816:Palaeoannelida
3810:
3808:
3803:
3801:
3793:
3789:long branching
3740:Lobatocerebrum
3723:Palaeoannelida
3645:
3644:
3641:
3640:
3636:
3635:
3632:
3631:
3626:
3623:
3622:
3619:
3618:
3614:
3613:
3610:
3609:
3605:
3604:
3601:
3600:
3596:
3595:
3592:
3591:
3586:
3583:
3582:
3579:
3578:
3568:
3563:
3561:
3558:
3557:
3554:
3553:
3548:
3543:
3541:
3538:
3537:
3534:
3533:
3529:
3528:
3525:
3524:
3520:
3519:
3516:
3515:
3511:
3510:
3507:
3506:
3501:
3498:
3497:
3494:
3493:
3489:
3488:
3485:
3484:
3474:
3471:
3470:
3467:
3466:
3461:
3456:
3454:
3449:
3447:
3444:
3443:
3440:
3439:
3434:
3431:
3430:
3427:
3426:
3422:
3421:
3418:
3417:
3413:
3412:
3409:
3408:
3405:Aeolosomatidae
3401:
3398:
3397:
3394:
3393:
3389:
3388:
3385:
3384:
3377:
3374:
3373:
3370:
3369:
3365:
3364:
3361:
3360:
3356:
3355:
3352:
3351:
3344:
3341:
3340:
3337:
3336:
3322:
3317:
3315:
3312:
3311:
3308:
3307:
3296:
3291:
3289:
3284:
3282:
3275:
3270:
3268:
3265:
3264:
3261:
3260:
3256:
3255:
3252:
3251:
3241:
3238:
3237:
3234:
3233:
3228:
3223:
3221:
3216:
3214:
3209:
3207:
3204:
3203:
3200:
3199:
3194:
3189:
3187:
3182:
3180:
3175:
3173:
3165:
3164:
3162:
3161:
3160:
3159:
3158:
3152:
3140:
3131:
3130:
3126:
3125:
3121:
3120:
3117:
3116:
3109:
3106:
3105:
3102:
3101:
3097:
3096:
3093:
3092:
3088:
3087:
3084:
3083:
3079:
3078:
3075:
3074:
3067:
3064:
3063:
3060:
3059:
3055:
3054:
3051:
3050:
3046:
3045:
3042:
3041:
3034:
3031:
3030:
3027:
3026:
3019:
3014:
3012:
3006:
3005:
3002:
3001:
2997:
2996:
2993:
2992:
2985:
2982:
2981:
2978:
2977:
2970:
2967:
2966:
2963:
2962:
2955:
2950:
2948:
2940:
2938:
2930:
2928:
2922:
2921:
2918:
2917:
2913:
2912:
2909:
2908:
2901:
2898:
2897:
2894:
2893:
2886:
2881:
2879:
2874:
2872:
2866:
2865:
2862:
2861:
2854:
2849:
2847:
2842:
2825:hirudinomorphs
2804:
2801:
2735:occurs in the
2725:Kootenayscolex
2619:Burgessochaeta
2541:
2538:
2530:
2527:
2511:biomineralized
2496:anticoagulants
2419:soil fertility
2414:
2411:
2319:soil fertility
2309:Charles Darwin
2305:
2302:
2258:hermaphrodites
2180:
2179:
2171:
2126:
2119:
2118:
2117:
2116:
2114:
2111:
2050:
2047:
2045:
2042:
2034:protonephridia
2011:carbon dioxide
1969:Filter feeders
1932:
1929:
1900:
1897:
1800:; and turning
1735:
1732:
1627:
1624:
1531:
1528:
1461:
1460:
1452:
1431: Pygidium
1378:
1371:
1370:
1369:
1368:
1366:
1363:
1361:
1358:
1355:
1354:
1351:
1348:
1345:
1339:
1336:
1332:
1331:
1326:
1323:
1320:
1314:
1311:
1307:
1306:
1303:
1300:
1289:
1285:
1284:
1281:
1278:
1275:
1271:
1270:
1267:
1264:
1260:
1259:
1256:
1253:
1250:
1247:
1244:
1240:
1239:
1236:
1230:
1227:
1224:
1221:
1217:
1216:
1211:
1206:
1201:
1196:
1190:
1189:
1186:
1183:
1180:
1177:
1133:nervous system
1104:
1101:
1077:
1076:
1038:
1001:
985:
978:Vestimentifera
968:Pogonophora /
950:
949:
948:
947:
929:
878:
877:
869:
862:
861:
860:
859:
858:
857:
817:
814:
745:soil fertility
658:Lophotrochozoa
577:, are a large
482:
481:
480:
479:
473:
465:
457:
449:
441:
440:
439:
430:
425:
405:
382:
381:
380:
379:
378:
377:
372:
367:
362:
361:
360:
355:
345:
340:
335:
330:
325:
315:
314:
313:
312:
311:
306:
296:
286:
276:
273:Lobatocerebrum
269:
264:
259:
254:
252:Palaeoannelida
245:Cladistic view
239:
238:
234:
233:
221:
217:
216:
214:Lophotrochozoa
211:
207:
206:
201:
197:
196:
191:
187:
186:
181:
174:
173:
168:
161:
160:
155:
151:
150:
145:
141:
140:
127:
126:
122:
121:
113:
112:
99:
94:
89:
84:
79:
74:
69:
64:
59:
54:
49:
44:
37:
26:
9:
6:
4:
3:
2:
11201:
11190:
11187:
11185:
11182:
11180:
11177:
11176:
11174:
11157:
11152:
11148:
11144:
11138:
11134:
11129:
11125:
11121:
11116:
11112:
11108:
11102:
11098:
11093:
11089:
11085:
11080:
11076:
11072:
11067:
11063:
11059:
11054:
11050:
11046:
11041:
11037:
11033:
11028:
11024:
11020:
11015:
11011:
11007:
11002:
10998:
10994:
10989:
10985:
10981:
10976:
10972:
10968:
10963:
10959:
10955:
10950:
10946:
10941:
10935:
10931:
10926:
10920:
10916:
10915:
10913:
10911:
10907:
10903:
10898:
10884:
10883:
10878:
10876:
10875:
10870:
10860:
10857:
10855:
10852:
10850:
10847:
10845:
10842:
10840:
10837:
10835:
10832:
10830:
10827:
10825:
10822:
10820:
10817:
10815:
10812:
10810:
10807:
10805:
10802:
10800:
10797:
10795:
10792:
10790:
10787:
10785:
10782:
10780:
10777:
10775:
10772:
10770:
10767:
10765:
10762:
10760:
10757:
10755:
10752:
10750:
10747:
10745:
10742:
10740:
10737:
10735:
10732:
10730:
10727:
10725:
10722:
10720:
10717:
10715:
10712:
10710:
10707:
10705:
10702:
10700:
10697:
10696:
10694:
10692:
10688:
10682:
10679:
10677:
10674:
10672:
10669:
10667:
10664:
10662:
10659:
10657:
10654:
10652:
10649:
10647:
10644:
10642:
10639:
10637:
10634:
10632:
10629:
10627:
10624:
10622:
10619:
10617:
10614:
10613:
10611:
10609:
10605:
10599:
10598:Basidiomycota
10596:
10594:
10591:
10589:
10586:
10584:
10583:Glomeromycota
10581:
10579:
10576:
10574:
10571:
10569:
10566:
10565:
10563:
10561:
10557:
10551:
10548:
10546:
10545:Stramenopiles
10543:
10541:
10538:
10536:
10533:
10531:
10528:
10526:
10523:
10521:
10518:
10516:
10513:
10511:
10508:
10506:
10503:
10501:
10498:
10496:
10493:
10491:
10488:
10486:
10483:
10481:
10478:
10476:
10473:
10471:
10470:Apusomonadida
10468:
10466:
10463:
10461:
10458:
10456:
10453:
10452:
10450:
10447:
10442:
10439:
10437:
10433:
10423:
10420:
10418:
10415:
10413:
10410:
10407:
10406:Nanoarchaeota
10403:
10400:
10396:
10393:
10392:Euryarchaeota
10389:
10388:
10386:
10384:
10380:
10376:
10366:
10363:
10361:
10358:
10356:
10353:
10351:
10348:
10346:
10343:
10341:
10340:Spirochaetota
10338:
10336:
10335:Rhodothermota
10333:
10331:
10328:
10326:
10323:
10321:
10318:
10316:
10313:
10311:
10308:
10306:
10303:
10301:
10298:
10296:
10293:
10291:
10288:
10286:
10283:
10281:
10278:
10276:
10273:
10271:
10268:
10266:
10265:Dictyoglomota
10263:
10261:
10258:
10256:
10253:
10250:
10249:Cyanobacteria
10246:
10244:
10241:
10239:
10238:Chrysiogenota
10236:
10234:
10233:Chloroflexota
10231:
10229:
10226:
10224:
10221:
10219:
10216:
10214:
10213:Calditrichota
10211:
10209:
10208:Caldisericota
10206:
10204:
10201:
10199:
10196:
10194:
10191:
10189:
10186:
10184:
10183:Atribacterota
10181:
10179:
10176:
10174:
10171:
10169:
10166:
10164:
10161:
10160:
10158:
10156:
10152:
10148:
10144:
10139:
10131:
10126:
10124:
10119:
10117:
10112:
10111:
10108:
10095:
10094:dubious phyla
10091:
10089:
10085:
10084:
10081:
10069:
10066:
10064:
10061:
10059:
10056:
10054:
10051:
10049:
10046:
10045:
10044:
10043:
10039:
10035:
10032:
10030:
10027:
10025:
10022:
10021:
10020:
10019:
10015:
10011:
10008:
10006:
10003:
10001:
9998:
9997:
9996:
9995:
9991:
9987:
9984:
9982:
9979:
9977:
9974:
9972:
9969:
9968:
9967:
9966:
9962:
9958:
9955:
9953:
9950:
9948:
9945:
9943:
9940:
9939:
9938:
9937:
9933:
9929:
9926:
9924:
9921:
9919:
9916:
9915:
9914:
9913:
9909:
9905:
9902:
9900:
9897:
9896:
9895:
9894:
9893:Hemichordates
9890:
9886:
9883:
9881:
9878:
9876:
9873:
9872:
9871:
9870:
9866:
9862:
9859:
9857:
9854:
9852:
9849:
9848:
9847:
9846:
9842:
9838:
9835:
9833:
9830:
9828:
9825:
9824:
9823:
9822:
9818:
9814:
9811:
9809:
9808:Glass sponges
9806:
9804:
9801:
9800:
9799:
9798:
9794:
9793:
9791:
9785:
9781:
9774:
9760:
9757:
9755:
9752:
9750:
9749:Deuterostomia
9747:
9745:
9742:
9738:
9735:of Bilateria
9734:
9729:
9728:
9725:
9683:
9680:
9678:
9675:
9674:
9672:
9670:
9666:
9660:
9659:
9655:
9653:
9650:
9649:
9647:
9645:
9641:
9638:
9636:
9632:
9626:
9625:
9621:
9620:
9617:
9614:
9612:
9608:
9602:
9601:
9597:
9596:
9593:
9590:
9586:
9580:
9579:
9575:
9573:
9571:
9568:Cycliophora (
9566:
9565:
9562:
9559:
9556:
9551:
9536:
9534:
9529:
9527:
9524:
9522:
9519:
9518:
9516:
9514:
9510:
9504:
9501:
9499:
9498:
9494:
9493:
9491:
9489:
9485:
9482:
9478:
9474:
9471:
9468:
9463:
9447:
9446:
9442:
9440:
9439:
9435:
9434:
9433:
9430:
9428:
9427:
9422:
9421:
9419:
9415:
9409:
9406:
9404:
9401:
9400:
9397:
9394:
9392:
9388:
9384:
9381:
9378:
9373:
9347:
9346:
9342:
9340:
9339:
9335:
9334:
9332:
9330:
9326:
9320:
9317:
9316:
9313:
9310:
9308:
9307:Panarthropoda
9304:
9298:
9295:
9294:
9291:
9288:
9284:
9280:
9274:
9271:
9269:
9268:
9264:
9263:
9261:
9259:
9255:
9252:
9248:
9238:
9235:
9233:
9230:
9229:
9227:
9225:
9221:
9217:
9214:
9211:
9206:
9203:
9200:
9195:
9191:
9181:
9178:
9176:
9175:
9171:
9170:
9167:
9164:
9162:
9158:
9152:
9151:
9147:
9145:
9142:
9141:
9138:
9135:
9132:
9127:
9123:
9119:
9114:
9110:
9100:
9097:
9095:
9092:
9088:
9084:
9079:
9078:
9075:
9060:
9059:
9057:
9054:
9050:
9044:
9043:
9039:
9037:
9035:
9030:
9029:
9026:
9023:
9020:
9015:
9011:
9005:
9002:
9000:
8999:
8995:
8994:
8991:
8988:
8985:
8980:
8976:
8964:
8961:
8959:
8956:
8954:
8951:
8950:
8949:
8946:
8944:
8941:
8940:
8939:
8936:
8932:
8929:
8927:
8926:Stramenopiles
8924:
8922:
8919:
8917:
8914:
8910:
8907:
8906:
8905:
8902:
8901:
8900:
8897:
8895:
8892:
8889:(major groups
8887:
8885:
8882:
8880:
8877:
8875:
8872:
8869:
8865:
8864:
8860:
8856:
8853:
8845:
8840:
8838:
8833:
8831:
8826:
8825:
8822:
8815:
8810:
8806:
8803:
8798:
8794:
8793:
8780:
8776:
8772:
8768:
8763:
8758:
8754:
8750:
8746:
8742:
8738:
8731:
8717:
8711:
8707:
8703:
8696:
8688:
8684:
8679:
8674:
8669:
8664:
8660:
8656:
8652:
8648:
8644:
8637:
8629:
8625:
8621:
8617:
8613:
8609:
8605:
8601:
8597:
8593:
8586:
8578:
8574:
8570:
8566:
8562:
8558:
8554:
8550:
8546:
8542:
8535:
8527:
8523:
8519:
8517:9783110291469
8513:
8509:
8505:
8501:
8494:
8486:
8482:
8477:
8472:
8469:(1): 95–119.
8468:
8464:
8460:
8453:
8444:
8439:
8435:
8431:
8427:
8420:
8412:
8408:
8404:
8400:
8396:
8392:
8385:
8377:
8373:
8369:
8365:
8360:
8355:
8351:
8347:
8343:
8339:
8335:
8328:
8313:
8309:
8303:
8289:
8285:
8281:
8277:
8270:
8263:
8261:
8259:
8257:
8248:
8244:
8239:
8234:
8229:
8224:
8220:
8216:
8212:
8208:
8204:
8197:
8195:
8185:
8170:
8166:
8162:
8155:
8153:
8151:
8142:
8138:
8134:
8130:
8126:
8122:
8115:
8113:
8104:
8100:
8096:
8092:
8088:
8084:
8077:
8063:
8059:
8055:
8051:
8047:
8043:
8036:
8029:
8015:
8009:
8005:
7998:
7991:
7989:
7987:
7978:
7974:
7970:
7966:
7959:
7952:
7944:
7940:
7936:
7932:
7928:
7924:
7921:(2): 253–95.
7920:
7916:
7909:
7901:
7897:
7893:
7889:
7885:
7881:
7877:
7870:
7868:
7866:
7864:
7862:
7847:on 2013-07-11
7846:
7842:
7838:
7834:
7830:
7823:
7805:
7798:
7791:
7783:
7779:
7775:
7771:
7767:
7763:
7759:
7755:
7751:
7744:
7736:
7730:
7726:
7719:
7704:
7703:
7702:The Economist
7698:
7692:
7684:
7678:
7674:
7670:
7663:
7655:
7651:
7647:
7643:
7639:
7635:
7634:Hydrobiologia
7631:
7624:
7622:
7607:
7601:
7597:
7593:
7586:
7572:
7566:
7562:
7561:
7560:The worm book
7553:
7545:
7539:
7535:
7534:
7526:
7518:
7512:
7508:
7504:
7497:
7495:
7493:
7491:
7489:
7487:
7485:
7483:
7474:
7468:
7464:
7457:
7455:
7453:
7451:
7449:
7440:
7434:
7430:
7423:
7415:
7409:
7405:
7398:
7390:
7384:
7380:
7376:
7375:
7367:
7365:
7356:
7350:
7346:
7342:
7341:
7333:
7325:
7319:
7315:
7311:
7310:
7302:
7300:
7291:
7285:
7281:
7277:
7276:
7268:
7260:
7254:
7250:
7246:
7245:
7237:
7229:
7223:
7219:
7215:
7214:
7206:
7198:
7194:
7190:
7186:
7181:
7176:
7172:
7168:
7164:
7157:
7149:
7143:
7139:
7135:
7134:
7126:
7124:
7122:
7120:
7111:
7107:
7102:
7097:
7094:(2): 93–103.
7093:
7089:
7085:
7078:
7071:
7069:
7062:
7056:
7052:
7051:
7043:
7037:
7032:
7014:
7010:
7006:
7002:
6998:
6994:
6990:
6983:
6976:
6968:
6964:
6960:
6956:
6952:
6948:
6944:
6940:
6933:
6925:
6919:
6915:
6911:
6910:
6902:
6894:
6888:
6884:
6880:
6879:
6871:
6863:
6857:
6853:
6849:
6848:
6840:
6832:
6826:
6822:
6815:
6807:
6801:
6797:
6793:
6792:
6784:
6776:
6770:
6766:
6762:
6761:
6753:
6751:
6742:
6738:
6734:
6730:
6726:
6722:
6715:
6707:
6701:
6697:
6690:
6688:
6686:
6684:
6682:
6680:
6678:
6676:
6674:
6672:
6670:
6668:
6666:
6664:
6662:
6655:
6650:
6644:
6639:
6631:
6627:
6622:
6617:
6613:
6609:
6605:
6601:
6597:
6590:
6582:
6578:
6573:
6568:
6563:
6558:
6554:
6550:
6546:
6539:
6531:
6527:
6522:
6517:
6513:
6509:
6505:
6498:
6490:
6486:
6481:
6476:
6471:
6466:
6462:
6458:
6454:
6450:
6446:
6439:
6431:
6427:
6423:
6419:
6414:
6409:
6405:
6401:
6397:
6390:
6388:
6386:
6377:
6371:
6367:
6363:
6362:
6354:
6352:
6350:
6348:
6339:
6333:
6329:
6325:
6324:
6316:
6308:
6302:
6298:
6291:
6289:
6287:
6285:
6283:
6274:
6268:
6264:
6257:
6255:
6253:
6251:
6249:
6247:
6245:
6243:
6241:
6239:
6237:
6227:
6222:
6218:
6214:
6210:
6203:
6201:
6192:
6188:
6183:
6178:
6173:
6168:
6164:
6160:
6156:
6152:
6148:
6141:
6139:
6137:
6135:
6133:
6131:
6129:
6127:
6112:
6108:
6101:
6094:
6086:
6080:
6076:
6072:
6071:
6063:
6061:
6059:
6057:
6055:
6053:
6051:
6049:
6047:
6045:
6043:
6041:
6039:
6037:
6035:
6033:
6031:
6029:
6027:
6025:
6023:
6021:
6019:
6017:
6015:
6013:
6011:
6009:
6007:
6005:
6003:
6001:
5999:
5997:
5995:
5993:
5991:
5982:
5975:
5973:
5971:
5969:
5960:
5954:
5950:
5946:
5942:
5935:
5933:
5931:
5929:
5920:
5916:
5912:
5908:
5904:
5900:
5896:
5892:
5888:
5884:
5877:
5870:
5862:
5861:
5856:
5851:
5846:
5840:
5832:
5831:
5825:
5820:
5814:
5812:
5803:
5799:
5794:
5789:
5785:
5781:
5777:
5773:
5769:
5762:
5754:
5750:
5746:
5742:
5738:
5734:
5727:
5723:
5717:
5715:
5713:
5708:
5693:
5689:
5685:
5681:
5677:
5673:
5669:
5665:
5661:
5657:
5649:
5642:
5638:
5632:
5628:
5615:
5614:
5606:
5605:
5597:
5596:
5588:
5587:
5579:
5578:
5570:
5569:
5566:
5565:
5559:
5558:
5555:
5554:
5551:
5549:
5539:
5538:
5535:
5534:
5526:
5525:
5522:
5521:
5515:
5514:
5511:
5510:
5507:
5506:
5500:
5499:
5493:
5492:
5486:
5485:
5482:
5481:
5478:
5477:
5476:
5466:
5465:
5459:
5458:
5454:
5453:
5450:
5449:
5441:
5440:
5437:
5436:
5430:
5429:
5426:
5425:
5422:
5421:
5420:
5419:Phragmochaeta
5410:
5409:
5403:
5402:
5396:
5395:
5392:
5391:
5383:
5382:
5374:
5373:
5370:
5369:
5368:
5361:
5360:
5357:
5356:
5353:
5352:
5351:
5341:
5340:
5334:
5333:
5330:
5329:
5326:
5325:
5324:
5314:
5313:
5307:
5306:
5300:
5299:
5296:
5295:
5292:
5291:
5290:
5283:
5282:
5276:
5273:
5272:
5268:
5266:
5262:
5259:
5255:
5251:
5247:
5243:
5242:lophophorates
5239:
5235:
5231:
5227:
5226:lophophorates
5218:
5214:
5212:
5208:
5204:
5200:
5190:
5189:
5181:
5180:
5172:
5171:
5163:
5162:
5154:
5153:
5145:
5144:
5136:
5135:
5127:
5126:
5118:
5117:
5114:
5112:
5108:
5102:
5101:
5098:
5097:
5089:
5088:
5080:
5079:
5076:
5074:
5070:
5064:
5063:
5060:
5059:
5056:
5054:
5050:
5044:
5043:
5037:
5034:
5033:
5030:
5029:
5021:
5020:
5017:
5014:
5009:
5003:
5002:
4999:
4998:
4995:
4993:
4989:
4983:
4982:
4976:
4973:
4972:
4966:
4963:
4962:
4956:
4953:
4952:
4949:
4948:
4945:
4942:
4937:
4931:
4930:
4924:
4923:
4920:
4919:
4916:
4915:
4909:
4908:
4905:
4904:
4901:
4898:
4893:
4887:
4886:
4880:
4877:
4876:
4873:
4872:
4864:
4863:
4860:
4857:
4852:
4846:
4845:
4842:
4841:
4838:
4836:
4832:
4826:
4825:
4819:
4818:
4812:
4809:
4808:
4805:
4804:
4801:
4798:
4793:
4787:
4786:
4780:
4777:
4776:
4773:
4772:
4769:
4767:
4762:
4758:
4752:
4751:
4745:
4742:
4741:
4738:
4737:
4734:
4732:
4728:
4724:
4723:Deuterostomia
4718:
4717:
4711:
4710:
4707:
4706:
4703:
4701:
4697:
4693:
4687:
4686:
4680:
4677:
4676:
4672:
4670:
4666:
4662:
4658:
4654:
4650:
4646:
4642:
4641:independently
4638:
4634:
4630:
4626:
4625:deuterostomes
4622:
4618:
4614:
4599:
4598:
4590:
4589:
4581:
4580:
4572:
4571:
4563:
4562:
4554:
4553:
4545:
4544:
4536:
4535:
4527:
4526:
4518:
4517:
4514:
4511:
4507:
4503:
4496:
4495:
4492:
4491:
4483:
4482:
4479:
4478:
4477:Maldanomorpha
4472:
4471:
4468:
4467:
4464:
4463:
4457:
4456:
4450:
4449:
4443:
4442:
4439:
4438:
4430:
4429:
4421:
4420:
4417:
4416:
4410:
4409:
4406:
4405:
4402:
4401:
4395:
4394:
4388:
4385:
4384:
4381:
4380:
4377:
4376:
4370:
4369:
4363:
4362:
4356:
4355:
4352:
4351:
4343:
4342:
4334:
4333:
4330:
4329:
4323:
4322:
4319:
4318:
4315:
4314:
4308:
4307:
4301:
4300:
4297:
4296:
4288:
4287:
4284:
4282:
4276:
4275:
4272:
4271:
4268:
4267:
4261:
4260:
4254:
4253:
4247:
4246:
4240:
4239:
4236:
4235:
4232:
4231:
4225:
4224:
4218:
4215:
4214:
4211:
4210:
4207:
4206:
4200:
4197:
4196:
4193:
4192:
4184:
4183:
4175:
4174:
4171:
4170:
4164:
4163:
4160:
4159:
4156:
4155:
4154:Polygordiidae
4149:
4148:
4142:
4139:
4138:
4135:
4134:
4126:
4125:
4122:
4121:
4115:
4114:
4111:
4110:
4107:
4106:
4100:
4099:
4093:
4090:
4089:
4083:
4080:
4079:
4073:
4070:
4069:
4063:
4062:
4059:
4058:
4050:
4049:
4041:
4040:
4037:
4036:
4030:
4029:
4026:
4025:
4022:
4021:
4020:
4013:
4012:
4006:
4005:
4002:
4001:
3998:
3997:
3991:
3990:
3984:
3983:
3977:
3976:
3973:
3972:
3964:
3963:
3955:
3954:
3946:
3945:
3942:
3941:
3935:
3934:
3931:
3930:
3927:
3926:
3920:
3919:
3913:
3912:
3909:
3908:
3905:
3904:
3903:
3896:
3895:
3889:
3886:
3885:
3879:
3878:
3872:
3871:
3868:
3867:
3859:
3858:
3850:
3849:
3846:
3845:
3839:
3838:
3835:
3834:
3831:
3830:
3824:
3823:
3817:
3814:
3813:
3807:
3806:
3800:
3797:
3796:
3792:
3790:
3786:
3782:
3778:
3775:contains the
3774:
3770:
3766:
3765:pogonophorans
3762:
3759:contains the
3758:
3754:
3750:
3746:
3742:
3741:
3736:
3732:
3728:
3724:
3720:
3716:
3711:
3709:
3708:invertebrates
3705:
3699:
3696:
3692:
3688:
3684:
3679:
3677:
3673:
3669:
3668:pogonophorans
3665:
3658:
3654:
3643:
3642:
3634:
3633:
3630:
3625:
3624:
3621:
3620:
3612:
3611:
3603:
3602:
3594:
3593:
3590:
3585:
3584:
3581:
3580:
3577:
3574:
3567:
3566:
3560:
3559:
3556:
3555:
3552:
3547:
3546:
3540:
3539:
3536:
3535:
3527:
3526:
3518:
3517:
3509:
3508:
3505:
3500:
3499:
3496:
3495:
3487:
3486:
3483:
3480:
3473:
3472:
3469:
3468:
3465:
3460:
3459:
3453:
3452:
3446:
3445:
3442:
3441:
3438:
3433:
3432:
3429:
3428:
3420:
3419:
3411:
3410:
3407:
3406:
3400:
3399:
3396:
3395:
3387:
3386:
3383:
3376:
3375:
3372:
3371:
3363:
3362:
3354:
3353:
3350:
3343:
3342:
3339:
3338:
3335:
3332:
3328:
3321:
3320:
3314:
3313:
3310:
3309:
3306:
3303:
3295:
3294:
3288:
3287:
3279:
3274:
3273:
3267:
3266:
3263:
3262:
3254:
3253:
3250:
3247:
3240:
3239:
3236:
3235:
3232:
3227:
3226:
3220:
3219:
3213:
3212:
3206:
3205:
3202:
3201:
3198:
3193:
3192:
3186:
3185:
3179:
3178:
3172:
3169:
3168:
3156:
3153:
3150:
3149:Canalipalpata
3147:
3146:
3144:
3141:
3138:
3135:
3134:
3128:
3127:
3119:
3118:
3115:
3114:
3108:
3107:
3104:
3103:
3095:
3094:
3086:
3085:
3077:
3076:
3073:
3072:
3066:
3065:
3062:
3061:
3053:
3052:
3044:
3043:
3040:
3039:
3033:
3032:
3029:
3028:
3025:
3024:
3018:
3017:
3011:
3008:
3007:
3004:
3003:
2995:
2994:
2991:
2990:
2984:
2983:
2980:
2979:
2976:
2975:
2969:
2968:
2965:
2964:
2961:
2960:
2954:
2953:
2947:
2946:Canalipalpata
2944:
2943:
2937:
2934:
2933:
2927:
2924:
2923:
2920:
2919:
2911:
2910:
2907:
2906:
2900:
2899:
2896:
2895:
2892:
2891:
2885:
2884:
2878:
2877:
2871:
2868:
2867:
2864:
2863:
2860:
2859:
2853:
2852:
2846:
2845:
2841:
2840:
2837:
2834:
2830:
2826:
2822:
2818:
2814:
2810:
2800:
2796:
2791:
2787:
2781:
2776:
2772:
2768:
2764:
2758:
2753:
2750:in the early
2749:
2743:
2738:
2734:
2729:
2727:
2726:
2721:
2717:
2716:Burgess shale
2711:
2706:
2702:
2696:
2691:
2690:Carboniferous
2685:
2680:
2676:
2672:
2671:
2664:
2659:
2658:Sirius Passet
2655:
2654:
2653:Phragmochaeta
2649:
2645:
2644:
2639:
2636:
2630:
2625:
2624:Burgess Shale
2621:
2620:
2615:
2614:
2609:
2605:
2601:
2595:
2590:
2589:
2585:
2581:
2577:
2576:
2571:
2567:
2563:
2559:
2552:
2551:
2546:
2540:Fossil record
2536:
2526:
2524:
2520:
2516:
2512:
2507:
2505:
2501:
2497:
2493:
2490:has provided
2489:
2485:
2481:
2477:
2473:
2472:
2466:
2465:blood-letting
2462:
2457:
2454:
2452:
2448:
2444:
2440:
2436:
2432:
2428:
2424:
2420:
2410:
2408:
2404:
2401:
2397:
2393:
2389:
2384:
2382:
2378:
2374:
2370:
2365:
2361:
2359:
2358:
2351:
2349:
2345:
2341:
2337:
2332:
2331:decomposition
2328:
2324:
2320:
2316:
2315:
2310:
2301:
2298:
2294:
2290:
2286:
2282:
2278:
2274:
2270:
2265:
2263:
2259:
2253:
2251:
2247:
2243:
2239:
2234:
2231:
2227:
2223:
2219:
2215:
2211:
2208:
2204:
2200:
2196:
2192:
2182:
2175:
2123:
2110:
2108:
2107:
2102:
2101:
2096:
2091:
2089:
2085:
2083:
2078:
2074:
2070:
2064:
2060:
2055:
2041:
2039:
2035:
2031:
2030:metanephridia
2026:
2024:
2020:
2016:
2012:
2008:
2004:
2000:
1997:
1993:
1989:
1984:
1982:
1978:
1974:
1970:
1966:
1965:Phyllodocidae
1962:
1958:
1953:
1945:
1941:
1937:
1928:
1926:
1922:
1918:
1914:
1910:
1906:
1896:
1894:
1889:
1884:
1881:
1876:
1872:
1868:
1867:chlorocruorin
1864:
1860:
1855:
1853:
1849:
1844:
1840:
1832:
1817:
1815:
1811:
1807:
1803:
1799:
1795:
1791:
1787:
1783:
1779:
1775:
1770:
1766:
1761:
1757:
1753:
1749:
1745:
1741:
1731:
1728:
1724:
1719:
1715:
1714:compound eyes
1711:
1707:
1703:
1699:
1693:
1691:
1687:
1683:
1679:
1674:
1672:
1668:
1665:
1661:
1657:
1653:
1649:
1645:
1641:
1637:
1633:
1623:
1621:
1617:
1613:
1607:
1605:
1601:
1597:
1593:
1589:
1585:
1581:
1577:
1572:
1570:
1569:plesiomorphic
1566:
1562:
1558:
1554:
1550:
1545:
1536:
1527:
1525:
1521:
1516:
1514:
1510:
1504:
1502:
1498:
1494:
1491:contains the
1490:
1486:
1482:
1478:
1473:
1463:
1456:
1443:
1407:
1375:
1344:
1340:
1334:
1333:
1330:
1324:
1321:
1319:
1315:
1309:
1308:
1298:
1294:
1290:
1287:
1286:
1272:
1261:
1254:
1241:
1235:
1231:
1228:
1218:
1215:
1212:
1210:
1207:
1205:
1202:
1200:
1197:
1195:
1192:
1184:
1168:
1166:
1165:blood vessels
1162:
1158:
1154:
1151:and does not
1150:
1146:
1142:
1138:
1134:
1130:
1126:
1122:
1118:
1114:
1110:
1100:
1098:
1094:
1090:
1086:
1082:
1074:
1073:pogonophorans
1070:
1066:
1062:
1061:mitochondrion
1058:
1054:
1053:developmental
1050:
1046:
1042:
1039:
1036:
1032:
1028:
1024:
1020:
1017:
1013:
1009:
1005:
1002:
999:
994:
990:
986:
983:
979:
975:
971:
967:
966:
965:
963:
959:
955:
954:Archiannelida
945:
941:
937:
933:
930:
927:
923:
919:
916:
915:
913:
909:
905:
901:
900:nuchal organs
897:
894:
893:
889:
885:
880:
873:
866:
855:
851:
850:nuchal organs
847:
843:
840:
839:
838:
835:
834:
829:
828:
823:
813:
811:
805:
800:
797:from the mid
796:
790:
785:
784:Carboniferous
781:
778:in the early
775:
770:
766:
762:
757:
754:
753:blood-letting
750:
746:
742:
738:
734:
730:
725:
723:
719:
714:
710:
706:
705:blood vessels
702:
698:
694:
690:
686:
682:
677:
675:
671:
667:
663:
659:
655:
651:
647:
643:
639:
635:
631:
627:
623:
619:
615:
614:triploblastic
611:
606:
604:
600:
596:
592:
588:
584:
580:
576:
572:
570:
565:
559:
527:
521:
489:
478:
474:
469:
466:
461:
458:
453:
450:
445:
442:
438:
434:
431:
429:
426:
422:
416:
412:
411:
410:
406:
402:
396:
392:
391:
390:
388:
376:
373:
371:
370:Maldanomorpha
368:
366:
363:
359:
356:
354:
351:
350:
349:
346:
344:
341:
339:
336:
334:
331:
329:
326:
324:
321:
320:
319:
316:
310:
307:
305:
302:
301:
300:
297:
295:
292:
291:
290:
287:
285:
282:
281:
280:
277:
275:
274:
270:
268:
265:
263:
260:
258:
255:
253:
250:
249:
248:
246:
240:
235:
230:
225:
222:
219:
218:
215:
212:
210:Superphylum:
209:
208:
205:
202:
199:
198:
195:
192:
189:
188:
185:
182:
179:
176:
175:
172:
169:
166:
163:
162:
159:
156:
153:
152:
149:
146:
143:
142:
137:
132:
128:
123:
119:
114:
109:
102:
97:
92:
87:
82:
77:
72:
67:
62:
57:
52:
47:
33:
30:
19:
10909:
10880:
10872:
10858:
10794:Orthonectida
10789:Gastrotricha
10764:Nematomorpha
10739:Chaetognatha
10729:Hemichordate
10656:Pteridophyta
10525:Malawimonada
10399:Korarchaeota
10360:Thermotogota
10345:Synergistota
10320:Nitrospirota
10315:Nitrospinota
10260:Deinococcota
10193:Bacteroidota
10092:Potentially
10087:
10040:
10017:
10016:
10010:Gymnolaemata
10005:Stenolaemata
9994:Ectoproctans
9992:
9963:
9934:
9910:
9904:Pterobranchs
9891:
9867:
9843:
9819:
9795:
9789:within phyla
9787:Major groups
9657:
9644:Bryozoa s.l.
9635:Lophophorata
9623:
9599:
9577:
9576:
9569:
9532:
9521:Orthonectida
9496:
9443:
9436:
9425:
9344:
9337:
9266:
9224:Scalidophora
9173:
9161:Ambulacraria
9148:
9061:(see below↓)
9041:
9033:
8997:
8948:Opisthokonta
8744:
8740:
8730:
8719:. Retrieved
8705:
8695:
8650:
8646:
8636:
8595:
8591:
8585:
8544:
8540:
8534:
8499:
8493:
8466:
8462:
8452:
8433:
8429:
8419:
8394:
8390:
8384:
8341:
8337:
8327:
8316:. Retrieved
8302:
8291:. Retrieved
8279:
8275:
8210:
8206:
8184:
8173:. Retrieved
8164:
8124:
8120:
8086:
8082:
8076:
8065:. Retrieved
8045:
8041:
8028:
8017:. Retrieved
8003:
7968:
7964:
7951:
7918:
7914:
7908:
7886:(1): 57–69.
7883:
7879:
7875:
7849:. Retrieved
7845:the original
7832:
7822:
7811:. Retrieved
7790:
7757:
7754:Paleobiology
7753:
7743:
7724:
7718:
7707:. Retrieved
7700:
7691:
7672:
7662:
7637:
7633:
7629:
7609:. Retrieved
7595:
7585:
7574:. Retrieved
7559:
7552:
7532:
7525:
7506:
7462:
7428:
7422:
7403:
7397:
7373:
7339:
7332:
7308:
7274:
7267:
7243:
7236:
7212:
7205:
7170:
7166:
7156:
7132:
7091:
7087:
7077:
7067:
7064:
7049:
7042:
7031:
7020:. Retrieved
6992:
6988:
6975:
6942:
6938:
6932:
6908:
6901:
6877:
6870:
6846:
6839:
6820:
6814:
6790:
6783:
6759:
6724:
6720:
6714:
6695:
6649:
6638:
6606:(1): 56–59.
6603:
6599:
6589:
6552:
6549:BMC Genomics
6548:
6538:
6511:
6507:
6497:
6452:
6448:
6438:
6403:
6399:
6360:
6322:
6315:
6296:
6262:
6216:
6212:
6154:
6150:
6114:. Retrieved
6110:
6106:
6093:
6069:
5980:
5940:
5886:
5882:
5869:
5858:
5839:
5828:
5775:
5771:
5761:
5736:
5732:
5659:
5655:
5648:
5640:
5631:
5562:
5542:
5518:
5503:
5473:
5469:
5457:Lophophorata
5455:
5434:
5433:
5417:
5413:
5365:
5364:
5348:
5344:
5321:
5317:
5287:
5286:
5252:secreted by
5246:sister group
5223:
5196:
5105:
5067:
5047:
5006:
4986:
4965:Lophophorata
4934:
4913:
4912:
4890:
4849:
4829:
4790:
4755:
4721:
4692:Acoelomorpha
4690:
4610:
4506:oligochaetes
4499:
4475:
4460:
4413:
4400:Capitellidae
4398:
4373:
4326:
4311:
4281:Siboglinidae
4279:
4264:
4228:
4203:
4198:
4169:Protodrilida
4167:
4152:
4120:Phyllodocida
4118:
4103:
4033:
4017:
4016:
3994:
3938:
3923:
3900:
3899:
3842:
3827:
3798:
3738:
3713:The updated
3712:
3704:segmentation
3700:
3695:sister-group
3687:tree of life
3680:
3661:
3652:
3650:
3628:
3588:
3573:Siboglinidae
3570:
3550:
3503:
3476:
3463:
3436:
3403:
3379:
3346:
3324:
3298:
3243:
3230:
3196:
3111:
3069:
3036:
3023:Phyllodocida
3021:
2987:
2972:
2957:
2903:
2890:Euarthropoda
2888:
2856:
2817:oligochaetes
2806:
2786:Body fossils
2777:period from
2763:trace fossil
2733:oligochaetes
2730:
2723:
2707:, less than
2668:
2651:
2641:
2617:
2611:
2608:sea anemones
2586:
2573:
2555:
2548:
2508:
2486:, and their
2484:microsurgery
2469:
2458:
2455:
2453:operations.
2416:
2396:oligochaetes
2385:
2366:
2362:
2355:
2352:
2312:
2307:
2285:spermathecae
2267:Most mature
2266:
2254:
2244:but produce
2235:
2218:metamorphose
2188:
2104:
2100:Chaetopterus
2098:
2092:
2080:
2077:oligochaetes
2067:
2061:tubeworm is
2027:
1992:Siboglinidae
1985:
1949:
1902:
1885:
1871:blood plasma
1856:
1836:
1737:
1702:chemosensors
1694:
1675:
1666:
1629:
1608:
1573:
1541:
1523:
1517:
1505:
1469:
1441:
1405:
1365:Segmentation
1310:Body cavity
1109:invertebrate
1106:
1081:Orthonectida
1078:
970:Siboglinidae
951:
918:Oligochaetes
854:chemosensors
831:
825:
819:
795:body fossils
758:
726:
678:
634:oligochaetes
622:invertebrate
607:
574:
566:
525:
487:
485:
471:(old phylum)
463:(old phylum)
455:(old phylum)
447:(old phylum)
421:paraphyletic
401:paraphyletic
386:
384:
358:Capitellidae
333:Siboglinidae
304:Phyllodocida
271:
244:
242:
223:
200:(unranked):
190:(unranked):
177:
164:
29:
11053:iNaturalist
10934:Wikispecies
10849:Brachiopoda
10824:Cycliophora
10769:Onychophora
10744:Kinorhyncha
10666:Ginkgophyta
10661:Cycadophyta
10626:Chlorophyta
10616:Glaucophyta
10310:Myxococcota
10228:Chlorobiota
10223:Chlamydiota
10068:Tusk shells
10053:Cephalopods
10024:Polychaetes
9971:Turbellaria
9952:Crustaceans
9928:Secernentea
9918:Chromadorea
9899:Acorn worms
9869:Echinoderms
9861:Vertebrates
9803:Demosponges
9737:is disputed
9199:Protostomia
9087:is disputed
9014:ParaHoxozoa
8282:: 229–256.
7705:. July 2008
5564:Brachiopoda
5267:structure.
5236:fossils, a
4988:Brachiopoda
4892:Cycliophora
4744:Protostomia
4657:trochophore
4653:lophophores
4649:brachiopods
4629:vertebrates
4613:protostomes
4387:Capitellida
4205:Myzostomida
3996:Amphinomida
3844:Magelonidae
3785:Myzostomida
3781:phyllodocid
3761:clitellates
3731:Amphinomida
3691:sipunculans
3302:Oligochaeta
2974:Terebellida
2905:Onychophora
2813:clitellates
2809:polychaetes
2580:polychaetes
2575:Dickinsonia
2566:mineralized
2562:Polychaetes
2558:soft-bodied
2451:aquaculture
2447:polychaetes
2443:aquaculture
2425:, a marine
2423:Palolo worm
2405:that cause
2400:myxosporean
2392:flagellates
2373:tidal zones
2369:coral reefs
2323:leaf litter
2291:produces a
2269:clitellates
2238:polychaetes
2222:apical tuft
2207:trochophore
2106:Dodecaceria
2069:Polychaetes
1981:clitellates
1917:clitellates
1913:polychaetes
1909:respiration
1899:Respiration
1875:capillaries
1839:peristalsis
1831:Peristalsis
1802:nitrogenous
1756:mesothelium
1748:mesenteries
1710:camera eyes
1686:Vertebrates
1648:polychaetes
1644:polychaetes
1551:-secreting
1501:polychaetes
1497:peristomium
1472:Diurodrilus
1411: Mouth
1360:Description
1293:polychaetes
1214:Onychophora
1097:Magelonidae
1065:Myzostomida
1023:tardigrades
1012:echinoderms
1004:Myzostomida
908:pack saddle
896:Clitellates
842:Polychaetes
765:mineralized
761:soft-bodied
729:food chains
713:undulations
709:peristalsis
670:brachiopods
662:protostomes
646:Pogonophora
630:polychaetes
599:tidal zones
477:Machaeridia
468:Pogonophora
460:Myzostomida
415:Oligochaeta
348:Capitellida
284:Myzostomida
267:Sipunculida
262:Amphinomida
194:Protostomia
11173:Categories
10882:Parakaryon
10844:Entoprocta
10779:Arthropoda
10774:Tardigrada
10754:Priapulida
10749:Loricifera
10734:Echinoderm
10704:Ctenophora
10676:Gnetophyta
10631:Charophyta
10621:Rhodophyta
10593:Ascomycota
10588:Zygomycota
10530:Metamonada
10505:Euglenozoa
10490:Ciliophora
10198:Balneolota
10173:Aquificota
10048:Gastropods
10029:Clitellata
9936:Arthropods
9875:Sea lilies
9821:Cnidarians
9739:; see also
9669:Brachiozoa
9432:Syndermata
9391:Gnathifera
9089:; see also
9034:Trichoplax
9032:Placozoa (
9019:Planulozoa
8721:2009-07-03
8318:2009-04-13
8293:2009-04-17
8175:2009-04-13
8067:2009-04-13
8019:2009-04-13
7851:2012-08-29
7813:2009-04-12
7709:2009-04-20
7611:2009-04-12
7576:2009-04-02
7438:0030259827
7022:2009-03-11
6727:(8): 953.
6116:2009-04-20
5703:References
5548:Tommotiids
5475:Wufengella
5350:Kimberella
5256:; paired,
5254:microvilli
5240:found the
5203:nemerteans
5069:Ectoprocta
5049:Entoprocta
4975:Brachiozoa
4792:Gnathifera
4761:Arthropods
4637:Articulata
4633:arthropods
4621:bilaterian
4617:superphyla
4502:Clitellata
4217:Sedentaria
3757:Sedentaria
3749:Sedentaria
3653:simplified
3278:Clitellata
2870:Articulata
2821:earthworms
2790:Ordovician
2752:Cretaceous
2679:Ordovician
2533:See also:
2427:polychaete
2273:earthworms
2226:prototroch
2082:Aulophorus
2079:, such as
1905:earthworms
1880:earthworms
1863:hemoglobin
1794:hemoglobin
1723:statocysts
1678:arthropods
1604:arthropods
1596:microvilli
1481:prostomium
1447: Anus
1209:Arthropoda
1157:arthropods
1089:nemerteans
1021:or of the
1010:and other
922:earthworms
799:Ordovician
756:strength.
737:ecosystems
689:locomotion
674:nemerteans
591:earthworms
585:including
409:Clitellata
395:Polychaeta
375:Clitellata
318:Sedentaria
18:Chaetopoda
10799:Dicyemida
10671:Pinophyta
10550:Telonemia
10485:Cryptista
10475:Breviatea
10460:Amoebozoa
10455:Alveolata
10436:Eukaryote
10188:Bacillota
10034:Sipuncula
9981:Monogenea
9976:Trematoda
9947:Myriapods
9912:Nematodes
9856:Tunicates
9851:Lancelets
9845:Chordates
9837:Myxozoans
9744:Nephrozoa
9733:phylogeny
9533:Salinella
9488:Rouphozoa
9329:Tactopoda
9258:Nematoida
9210:Ecdysozoa
9131:Bilateria
9118:Bilateria
9099:Benthozoa
9094:Eumetazoa
9083:phylogeny
9053:Bilateria
8943:Amoebozoa
8921:Alveolata
8909:Cryptista
8884:Eukaryota
8771:1879-0445
8526:242569001
7876:Myoscolex
7189:0960-9822
6157:(1): 57.
5641:annélides
5505:Phoronida
5258:metameric
5207:flatworms
5008:Phoronida
4831:Rouphozoa
4757:Ecdysozoa
4731:chordates
4679:Bilateria
4665:Ecdysozoa
4375:Opheliida
4313:Sabellida
4230:Orbiniida
4092:Aciculata
4035:Sipuncula
3829:Oweniidae
3769:echiurans
3735:Sipuncula
3672:echiurans
3327:Hirudinea
3246:Sipuncula
3155:Aciculata
3137:Scolecida
3113:Sipuncula
3071:Scolecida
3010:Aciculata
2959:Sabellida
2643:Myoscolex
2604:jellyfish
2600:cnidarian
2570:Ediacaran
2504:spreading
2409:in fish.
2403:parasites
2398:transmit
2289:clitellum
2203:nephridia
2003:inorganic
1996:symbiotic
1977:sediments
1961:Eunicidae
1925:parapodia
1915:and some
1893:inchworms
1886:However,
1843:parapodia
1792:-carrier
1763:modified
1740:coelomata
1671:epidermis
1592:follicles
1584:parapodia
1489:periproct
1318:proboscis
1283:α-chitin
1199:Sipuncula
1093:Oweniidae
1069:echiurans
1041:Sipuncula
1027:flatworms
1019:flatworms
1016:trematode
993:taxonomic
944:inchworms
940:parasites
932:Hirudinea
904:clitellum
888:clitellum
884:earthworm
846:parapodia
810:Paleogene
769:Ediacaran
718:pharynges
701:Sipuncula
685:parapodia
654:Sipuncula
642:Cladistic
626:parapodia
618:coelomate
444:Sipuncula
433:Hirudinea
338:Sabellida
323:Orbiniida
299:Aciculata
184:Nephrozoa
171:Bilateria
154:Kingdom:
148:Eukaryota
108:Ediacaran
106:Possible
11179:Annelids
10967:Annelida
10954:Annelida
10940:Annelida
10919:Wikidata
10910:Annelida
10859:Annelida
10854:Mollusca
10834:Phoronid
10829:Nemertea
10804:Rotifera
10784:Flatworm
10759:Nematoda
10724:Chordate
10714:Cnidaria
10709:Placozoa
10540:Rhizaria
10515:Haptista
10495:Cercozoa
10155:Bacteria
10058:Bivalves
10042:Molluscs
10018:Annelids
9377:Spiralia
8984:Animalia
8938:Amorphea
8916:Rhizaria
8904:Hacrobia
8894:Excavata
8879:Bacteria
8814:Annelida
8802:Annelida
8779:36170853
8687:10781038
8569:18322464
8485:83066199
8436:: 1–26.
8376:12919216
8368:26212885
8312:Archived
8169:Archived
8141:86797269
7943:39772232
7935:10881389
7900:85216629
7804:Archived
7782:84073818
7654:22669841
7197:38593767
7110:21672726
7013:Archived
6967:22020406
6959:15982370
6741:84995596
6643:Annelida
6630:19513266
6581:19327168
6530:17921486
6430:14782179
6422:21708764
6191:17411434
5911:23393261
5847:(1911).
5821:(1878).
5802:36417903
5753:35811524
5684:21368831
5435:Annelida
5367:Mollusca
5289:Nemertea
5261:coelomic
5211:cleavage
5199:molluscs
5107:Nemertea
4936:Mollusca
4914:Annelida
4779:Spiralia
4763:, etc.)
4645:molluscs
4328:Spionida
4105:Eunicida
4082:Errantia
3799:Annelida
3773:Errantia
3753:Errantia
3729:and the
3171:Annelida
3038:Eunicida
2989:Spionida
2926:Annelida
2833:families
2775:Triassic
2737:Tertiary
2718:beds in
2705:Jurassic
2692:, about
2681:, about
2660:, about
2638:Cambrian
2588:Cloudina
2519:proteins
2439:Ragworms
2377:sediment
2311:'s book
2281:copulate
2224:and the
2214:plankton
2154:Mesoderm
2084:furcatus
2059:sabellid
1999:bacteria
1957:families
1814:excreted
1798:proteins
1782:glycogen
1760:membrane
1698:ciliated
1580:traction
1544:collagen
1485:pygidium
1329:Hemocoel
1288:Molting
1277:Collagen
1204:Nemertea
1179:Annelida
1149:collagen
1145:secreted
1113:segments
1049:Mollusca
1045:bristles
1031:rotifers
1008:crinoids
1006:live on
801:, about
786:, about
780:Cambrian
722:sediment
681:segments
666:molluscs
587:ragworms
526:Annelida
488:annelids
343:Spionida
309:Eunicida
289:Errantia
224:Annelida
220:Phylum:
204:Spiralia
158:Animalia
144:Domain:
35:Annelida
10839:Bryozoa
10535:Provora
10510:Jakobea
10500:Discoba
10446:Protist
10383:Archaea
10136:Extant
10063:Chitons
9986:Cestoda
9923:Enoplea
9797:Sponges
9570:Symbion
9513:Mesozoa
8953:Animals
8874:Archaea
8850:Extant
8749:Bibcode
8655:Bibcode
8628:4334033
8620:9168109
8600:Bibcode
8577:4397099
8549:Bibcode
8411:5353873
8346:Bibcode
8247:9223304
8215:Bibcode
8091:Bibcode
8050:Bibcode
7762:Bibcode
7379:477–478
7345:466–469
7314:434–441
7280:196–224
7249:423–425
7218:103–104
7138:425–429
7009:1416582
6914:505–510
6883:518–521
6852:271–282
6796:490–495
6765:523–524
6621:2649304
6572:2667193
6555:: 136.
6489:9223304
6457:Bibcode
6366:471–482
6182:1855331
6159:Bibcode
6075:414–420
5919:6112274
5891:Bibcode
5883:Science
5857:(ed.).
5780:Bibcode
5692:4428998
5664:Bibcode
5520:Bryozoa
5323:Wiwaxia
5250:chaetae
5244:as the
4851:Mesozoa
4510:leeches
4415:Echiura
3777:eunicid
3479:Echiura
3331:leeches
3143:Palpata
2936:Palpata
2858:Echiura
2829:leeches
2792:, from
2754:, from
2701:sessile
2675:mollusc
2670:Wiwaxia
2633:in the
2613:Canadia
2591:, from
2515:calcium
2461:leeches
2435:Anglers
2388:leeches
2371:and in
2348:badgers
2297:ovaries
2277:leeches
2167:= cilia
2139:Stomach
2088:leeches
2073:budding
2063:budding
2019:methane
1952:pharynx
1888:leeches
1848:sessile
1806:ammonia
1640:ganglia
1636:pharynx
1524:annelus
1513:leeches
1477:chaetae
1297:leeches
1194:Echiura
1143:but is
1137:cuticle
1085:Mesozoa
989:Echiura
697:Echiura
650:Echiura
595:leeches
583:species
569:anellus
562:, from
475:Class †
452:Echiura
437:leeches
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353:Echiura
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11120:941620
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10699:Sponge
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2344:shrews
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2293:cocoon
2262:gonads
2210:larvae
2095:genera
1959:, the
1907:, all
1861:– red
1812:to be
1790:oxygen
1778:livers
1769:muscle
1727:genera
1706:ocelli
1682:neuron
1676:As in
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1121:organs
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10560:Fungi
10480:CRuMs
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8958:Fungi
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8522:S2CID
8481:S2CID
8407:S2CID
8372:S2CID
8272:(PDF)
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5230:phyla
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2771:fecal
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2502:from
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2431:Samoa
2250:penis
2199:sperm
2191:sexes
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2038:urine
2023:seeps
2021:from
2017:, or
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1921:gills
1852:cilia
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1744:septa
1690:axons
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1632:brain
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1616:cilia
1612:cirri
1600:setae
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1234:mites
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638:leech
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11097:6340
11092:NCBI
11079:ITIS
11040:GBIF
11001:EPPO
10975:BOLD
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10138:life
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2103:and
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1988:anus
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1305:Yes
1280:None
1258:Yes
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8757:doi
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