568:
1210:
1269:(the large posterior section of the body) by moving the abdominal plates, as such undulations of the opisthosoma and telson would have acted as the propulsive method of the animal, rendering the swimming legs used by other eurypterid groups useless. What is known of eurypterid anatomy contradicts the undulation hypothesis simply because eurypterid bodies were likely very stiff. The body segments were nearly equal in width and thickness with little difference in size between segments directly adjoining to each other, while there is no evidence for any sort of tapering or other mechanism that would have increased flexibility. Any flexing of the body would require muscular contractions, but no major
1147:
113:
667:
1171:; the capture and cutting of food into smaller pieces and transport of food into the mouth as well as defense. Though most other eurypterid families had simple pincers, the Pterygotidae is the only eurypterid family to possess enlarged and robust chelicerae with claws and teeth, showing unique adaptations to defense and/or prey capture. The chelicerae were composed of several joints, though the exact number is somewhat controversial with some researchers stating three, others four and some claiming that the number of joints varies between three and five depending on the species and genus in question (
1050:. Their remains range in age from 428 to 372 million years old (for a total temporal range of approximately 56 million years), reaching their greatest diversity during the Late Silurian, a period in time when other eurypterid groups became increasingly diverse as well. The enlargement and specialisation of the chelicerae within the Pterygotidae has been recognised as one of the two most striking evolutionary innovations within the Eurypterida, besides the transformation of the most posterior prosomal appendage into a swimming paddle (a trait seen in all eurypterids in the Eurypterina suborder).
2209:
1341:
1742:
521:
137:
2365:
184:
3576:
1290:
3879:
1196:, or "head"), would have been capable of turning the entire appendage in a twisting way, which has led researchers to conclude that the function of the chelicerae would not have been only, or even primarily, for defense but rather to capture and convey food to the mouth. When captured, prey would need to be broken into smaller pieces to be able to fit into the mouth; eurypterid mouths were even less adapted to devour large pieces than mouths of modern
1121:
protection in their prey. The pterygotids reached their maximum size and number in the Late
Silurian and Early Devonian, after which they saw rapid decline during the Devonian. This decline occurred at around the same time as there was an increase in unarmored vertebrates as well as a growth in fish size and the increased migration of fish into marine environments. The Devonian would also see the evolution of significantly faster-moving fish and the
1759:, and the consequential disturbance of character states historically interpreted as primitive and derived within the group when the error was solved. Subsequent descriptions and redescriptions have ensured that the phylogeny of the clade is rather robust at the genus level. Yet, a comprehensive species-level phylogenetic analysis has proven impossible due to the large amount of species based on scant and fragmentary fossilised material. The genus
1082:
1129:
are recorded together. There is also a recorded increase in fish diversity at the same time as the eurypterids began to decline in the early
Devonian, but available data does not support any direct competitive replacement. Though the pterygotids would be extinct at that point, both fish and eurypterids would decline in the Middle Devonian only to peak again in the late Devonian and to begin another decline in the
464:(frontal appendages) with claws. These claws were robust and possessed teeth which would have made many members of the group formidable predators. The strange proportions and large size of the pterygotid eurypterids led to the quarrymen who discovered the very first fossil remains of the group to give them the
1273:(internal ridges of the exoskeleton that supports muscular attachments) or any muscle scars indicative of large opisthosomal muscles have been found. Instead, pterygotids were most likely propelled by the enlarged and flattened paddlelike sixth pair of prosomal appendages, like other swimming eurypterids.
1112:
are often heavily armored, and it is likely that this represents an ancestral vertebrate trait that was later lost or reduced, rather than something that evolved separately in several groups at the same time. Some researchers have suggested that the armor was to protect against hitting rocky surfaces
2300:
are enlarged, as in other pterygotids, though the differentiated denticles and paired distal teeth mean that they were likely not used for specialised feeding, but solely for grasping. Though the number of lenses in its compound eyes is comparable to more derived members of the group, its morphology
1188:
has revealed that the actual count appears to be four joints. Additionally, a three-joint anatomy would have placed the claws at the end of appendages that would essentially have been rigid stalks, rendering their function useless. To have the necessary mobility, the pterygotid chelicerae would have
1120:
environments, they would seem to represent appropriate prey for the pterygotids, which were large predators with grasping claws. There are few other animals that would present appropriate prey and there are virtually no other predators than the pterygotids that would warrant the evolution of armored
2348:
have a very high visual acuity, which researchers could determine by observing low IOA values and large numbers of lenses in their compound eyes. The chelicerae of these genera were enlarged, robust and possessed a curved free ramus and denticles of different lengths and sizes, all adaptations that
1382:
Both Størmer (in 1974) and Erik N. Kjellesvig-Waering (in 1964) would come to consider the pterygotids as distinctive enough, due to their uniquely enlarged chelicerae, to warrant the status of a separate suborder, which was dubbed the "Pterygotina". More modern cladistics and phylogenetic analyses
1309:
at 2.1 metres). There are several known factors that restrict the size arthropods are able to grow to. These factors include respiration, the energy it costs to moult, locomotion and the properties of the exoskeleton. Except the cheliceral claws, which are robust and heavily sclerotized, a majority
1200:
are. The eurypterid walking appendages could not cut, transport or grasp anything, and as such this would also be done with the chelicerae. In crabs, the claws tear food apart and then transport the smaller pieces to the mouth. Based on the feeding process seen in modern arthropods with chelicerae,
1128:
The arguments of Romer were based on evolutionary trends in both groups and the fossil co-occurrences of both groups but he did not present a detailed analysis. The groups do frequently occur together, with pterygotids present at more than two-thirds of fossil localities where eurypterids and fish
475:
Studies on the cheliceral morphology and compound eyes of the pterygotids have revealed that the members of the group, despite overall morphological similarities, were highly divergent in their ecological roles. Pterygotid ecology ranged from generalized predatory behaviour in basal members of the
1327:
Though they were the largest arthropods known to have ever existed, the light-weight build of the pterygotids means that they are unlikely to have been the heaviest. Giant eurypterids of other lineages, notably the deep-bodied walking forms of the
Hibbertopteridae, such as the almost 2 metre long
511:
could be attributed to pressure from pterygotid predation and that later pterygotid decline could be attributed to subsequent evolutionary trends in fish. This hypothesis is mostly considered as far too simplistic of an explanation by modern researchers. Detailed analyses have failed to find any
1125:. These adaptations, potentially a result of pterygotid predation, would have significantly affected the likelihood of fish representing pterygotid prey and larger predatory fish may even have begun preying on pterygotids and other eurypterids, contributing to their decline and extinction.
1276:
An alternate hypothesis first proposed by C. D. Waterston in 1979 postulates that the median keel and the telson at large was used to steer the body, working more like a vertical and horizontal rudder than a tail fluke. Calculations and the creation of models of plaster allowed
Plotnick
2265:
and the interommatidial angle (abbreviated as IOA and referring to the angle between the optical axes of the adjacent lenses). The IOA is especially important as it can be used to distinguish different ecological roles in arthropods, being low in active predators.
1113:
in fast flowing streams, but Romer pointed out that there is no such armor protection in modern fish that live in that type of environment. Instead, Romer stated that the only reasonable explanation for the armor was as "a protection against living enemies".
642:. These appendages are the only ones that appear before the mouth and take the form of small pincers used to feed in all other eurypterid groups. In the pterygotids, the chelicerae were large and long, with strong well developed teeth on specialised
1776:). The cladogram also contains the primary unifying characteristics for the various clades, as well as the maximum sizes reached by the species in question, which have been suggested to possibly have been an evolutionary trait of the group per
2724:
The
Silurian System, Founded on Geological Researches in the Counties of Salop, Hereford, Radnor, Montgomery, Caermarthen, Brecon, Pembroke, Monmouth, Gloucester, Worcester, and Stafford: With Descriptions of the Coalfields and Overlying
2517:
Olive, Sébastien; Pradel, Alan; Martinez-Pérez, Carlos; Janvier, Philippe; Lamsdell, James C.; Gueriau, Pierre; Rabet, Nicolas; Duranleau-Gagnon, Philippe; Cardenas-Rozo, Andres L.; Zapata
Ramirez, Paula A.; Botella, Héctor (2019).
2260:
of the pterygotid eurypterids have revealed that it is possible to separate them into distinct ecological groups. The primary method for determining visual acuity in arthropods is by determining the number of lenses in their
2808:
646:(claws). These specialised chelicerae, likely used for prey capture but differing in the exact role from genus to genus, are also the primary feature that distinguishes members of the group from eurypterids of the other
1179:
five). The most common interpretation historically was that the number of joints were three, with a long basal joint followed by two smaller distal joints with teeth. More modern research on very complete specimens of
2316:
were low in visual acuity (with few lenses in the compound eyes and high IOA values), inconsistent with the traditionally assumed pterygotid lifestyle of "active and high-level visual predators". The IOA values of
1024:. Studies of specimens referred to this genus resolved long-standing contentiousness about the precise phylogenetic position of the Pterygotidae, providing evidence in the form of shared characteristics that
1281:(1988) to determine that the design of the pterygotid telson could functionally work as a rudder, which would have enabled the pterygotids to be agile animals capable of quick turns when chasing after prey.
1318:, are preserved as paper-thin compressions which suggests that pterygotids were very light-weight in construction. Similar adaptations have been observed in other prehistoric giant arthropods, such as
950:, was separated into a distinct genus in 1964 based on the supposed different segmentation of the genital appendage. These supposed differences would later turn out to be false, but briefly prompted
1755:
The clade
Pterygotidae is among the best supported within the Eurypterida. Relationships within it has historically been difficult to resolve due to wrong interpretations of genital appendage of
1367:
in 1912, the phylogenetic status of the
Pterygotidae has changed several times. Leif Størmer considered the group to represent a family within the eurypterid superfamily Eurypteracea. In 1962,
1046:
The pterygotids were one of the most successful eurypterid groups, with fossilised remains having been discovered on all continents except
Antarctica. They are the only eurypterid group with a
2321:
changed during ontogeny but in a way opposite to other pterygotids. Vision becomes less acute in larger specimens, whilst vision tends to get more acute in adults in other genera, such as in
3011:
Tetlie, O. E. (2008). "Hallipterus excelsior, a
Stylonurid (Chelicerata: Eurypterida) from the Late Devonian Catskill Delta Complex, and Its Phylogenetic Position in the Hardieopteridae".
1383:
does not support the classification of the pterygotids as a suborder, but classifies them within the superfamily Pterygotioidea as the most derived members of the suborder Eurypterina.
687:
Due to their unique features within the Eurypterida, the Pterygotidae has attracted a lot of attention ever since their discovery. The first fossils found, discovered by quarrymen in
1261:. The function of these specialised telsons has historically been controversial and disputed. Erik N. Kjellesvig-Waering compared the pterygotid telson to the large tail fluke of
552:
at 20 cm (7.9 in), to the largest known arthropods to have ever lived. Several species reached and exceeded 2 metres in length, the largest known species including
601:. In pterygotids, the outer surface of the exoskeletons, ranging in size from small to gigantic, was composed of semilunar scales. The chelicerate body is divided into two
703:
first thought the fossils represented remains of fish, with the name meaning "winged one", and only recognized their nature as arthropod remains five years later in 1844.
617:(the posteriormost division of the body) was expanded and flattened with a small median keel. The posterior margin (tip) of the telson forms a short spine in some genera (
3059:
Gould, Gina C.; MacFadden, Bruce J. (2004-06-01). "Chapter 17: Gigantism, Dwarfism, and Cope's Rule: "Nothing in Evolution Makes Sense without a Phylogeny"".
2884:
2991:"Fossil giants and surviving dwarfs. Arthropleurida and Pselaphognatha (Atelocerata, Diplopoda): characters, phylogenetic relationships and construction"
441:, exceeding 2 metres (6.6 ft) in length. Their fossilized remains have been recovered in deposits ranging in age from 428 to 372 million years old (
2325:. Pterygotids may thus have been almost equally visually acute early in their life cycle, becoming more differentiated during growth. The chelicerae of
1249:. The telson is in general flat but with a raised thin median keel. The posterior margin (tip) of the telson form a short spine in some genera, such as
791:) in 1935, differentiated by the curvature of the denticles (teeth) of the chelicerae. The same year (1935), Leif Størmer named a new pterygotid genus,
2892:
1116:
With most of the early vertebrates of the Silurian being just a few decimetres in length and often occurring together with pterygotid eurypterids in
954:
to be classified within a family of its own, the "Jaekelopteridae". The error with the genital appendage was later discovered and rectified, making
936:). Kjellesvig-Waering placed the primary taxonomical value on the morphology of the telson, considering potential differences in the chelicerae and
1018:
was recognized as being distinct from, and far more basal than, other species in its genus and was thus named as the type species of a new genus,
3970:
1061:, which is often interpreted as a sister-taxon of the Pterygotidae, as well as more derived pterygotids. The appendages were similar to those of
613:(abdomen). The appendages were attached to the prosoma, and were characterized in pterygotids by being small and slender and lacking spines. The
1163:
The function of pterygotid chelicerae was likely the same as the chelicerae of other eurypterids as well as those of other arthropods, such as
1310:
of fossilized large pterygotid body segments are unmineralized and thin. Even the plates that form the surface of the abdominal segments, the
1201:
one of the claws would hold the prey while the other would cut off pieces and transport it to the mouth with continuous and simple movements.
1133:. Detailed analyses have failed to find any correlation between the extinction of the pterygotids and the diversification of the vertebrates.
1311:
1297:
The Pterygotidae includes the largest known arthropods to have ever lived, with several species surpassing two metres in length (such as
2269:
Despite morphological similarities within the group, the ecology of the pterygotids differed greatly from genus to genus. The vision of
1386:
The cladogram below is simplified from a study by Tetlie (2007), showcasing the derived position of the pterygotids within Eurypterina.
1324:, and may be vital to the evolution of arthropod gigantism as a light-weight build decreases the influence of size-restricting factors.
1104:
suggested in 1933 that early vertebrate evolution might have been heavily influenced by pterygotid predation. Early vertebrates of the
3957:
3103:"All the better to see you with: eyes and claws reveal the evolution of divergent ecological roles in giant pterygotid eurypterids"
4049:
567:
4039:
3655:
3645:
3167:
2649:
2498:
1065:
but the carapace clearly belonged to a pterygotid, further suggesting a close relationship between the Pterygotidae and the
2854:
1293:
Size comparison of the largest recognized species of each pterygotid genus known from reasonably extensive fossil material.
1223:
The large and flattened pterygotid telson is a distinctive feature of the group that is only shared by the closely related
4044:
3607:
2524:
2520:"New insights into Late Devonian vertebrates and associated fauna from the Cuche Formation (Floresta Massif, Colombia)"
2757:
Kjellesvig-Waering, Erik N. (1964). "A Synopsis of the Family Pterygotidae Clarke and Ruedemann, 1912 (Eurypterida)".
2427:
Tetlie, O. Erik; Briggs, Derek E. G. (2009-09-01). "The origin of pterygotid eurypterids (Chelicerata: Eurypterida)".
3622:
2256:
Traditionally interpreted as visual and active predators as a group, recent studies on the cheliceral morphology and
452:
One of the most successful groups of eurypterids, the pterygotids were the only eurypterid family to achieve a truly
2824:
1209:
3866:
3650:
3592:
2383:
3101:
McCoy, Victoria E.; Lamsdell, James C.; Poschmann, Markus; Anderson, Ross P.; Briggs, Derek E. G. (2015-08-01).
2917:
3640:
3630:
3584:
2485:; E. N. K. Clarkson (1998). "Extinction and the fossil record of arthropods". In Gilbert Powell Larwood (ed.).
456:. Several evolutionary innovations made the pterygotids unique among the eurypterids, with large and flattened
3602:
3597:
3024:
2329:
likely served as slicing or shearing devices, adding to the evidence that it would have occupied a distinct
3635:
3612:
3072:
460:(the posteriormost division of the body) likely used as rudders to provide additional agility and enlarged
602:
183:
1371:
raised the groups in question to subordinal and superfamily status, Eurypteracea becoming the suborder
1368:
4034:
4029:
3268:
3160:
2678:
Plotnick, Roy E.; Baumiller, Tomasz K. (1988-01-01). "The pterygotid telson as a biological rudder".
2378:
1047:
453:
1146:
512:
correlation between the extinction of the pterygotids and the diversification of the vertebrates.
4024:
2490:
2296:
suggest that it was a generalised feeder rather than a highly specialised predator. The claws in
554:
503:
Some researchers have suggested that the pterygotid eurypterids evolved in something akin to an "
112:
4001:
3935:
3897:
3575:
718:
based on the morphology of the telsons of the species that had been assigned to it. He divided
586:
3049:. In Orlov, J. A. (ed.): Osnovy Paleontologii - volume 7, 404-423. Akademii Nauk SSSR, Moscow.
1766:
The cladogram below is based on the nine best-known pterygotid species and two outgroup taxa (
3996:
3988:
3975:
2153:
1192:
The first joint of the chelicerae, where it connects to the epistoma (a plate located on the
2855:"A new identity for the Silurian arthropod Necrogammarus | The Palaeontological Association"
3944:
3882:
3153:
2948:
2901:
2787:
2687:
2533:
2436:
1246:
2208:
666:
8:
2370:
711:
306:
2952:
2905:
2691:
2537:
2440:
3127:
3102:
3076:
3028:
2990:
2964:
2836:
2809:"Pterygotids (Chelicerata; Eurypterida) from the Silurian Vernon Formation of New York"
2766:
2699:
2620:
2593:
2559:
2460:
1340:
380:
178:
130:. The massive chelicerae of the pterygotids were their primary distinguishing feature.
3983:
3471:
3404:
3396:
3132:
2972:
2840:
2828:
2703:
2625:
2563:
2519:
2494:
2452:
2448:
1535:
1513:
1491:
1360:
1122:
736:
282:
3080:
3032:
2464:
1741:
3811:
3525:
3517:
3507:
3499:
3479:
3450:
3366:
3315:
3122:
3114:
3068:
3020:
2956:
2909:
2820:
2722:
2695:
2615:
2607:
2549:
2541:
2444:
2353:
and crustaceans. These genera likely represented active and visual apex predators.
2330:
2213:
1447:
1364:
740:
706:
By 1859, 10 species (many of which would later be reassigned) had been assigned to
520:
286:
136:
2545:
1265:
in 1964. The pterygotids were hypothesized to have moved by undulating the entire
1003:, both found in the same locality, but the lack of key diagnostic features in the
3840:
3686:
3543:
3484:
3440:
3343:
3330:
2913:
2598:
2388:
2173:
1585:
1101:
1030:
885:
655:
2960:
2337:
might have been a scavenger or ambush predator, feeding on soft-bodied animals.
3920:
3756:
3714:
3672:
3535:
3462:
3422:
3414:
3338:
2482:
1787:
1777:
1547:
1376:
1232:
1228:
1070:
647:
418:
264:
251:
892:
as the only genus within the Pterygotidae. In 1961, Kjellesvig-Waering raised
4018:
3763:
3735:
3728:
3700:
3679:
3432:
3371:
3361:
3353:
3307:
3297:
3289:
3245:
3209:
2832:
2707:
2456:
2282:
2262:
2257:
2218:
2022:
1469:
1299:
1150:
1105:
983:
981:
In 1986, Paul Selden examined the fossil material of the enigmatic arthropod
700:
643:
543:
539:
526:
484:
446:
442:
431:
362:
354:
312:
146:
70:
32:
28:
2477:
3721:
3489:
3445:
3320:
3136:
3118:
2976:
2629:
2611:
2478:
2242:
1954:
1936:
1911:
1893:
1861:
1801:
1772:
1747:
1561:
1320:
1020:
993:
987:
and concluded that the specimen represents the infracapitulum and attached
940:(a large plate that is part of the abdomen) to be secondary in importance.
793:
761:
728:
631:
573:
478:
346:
338:
295:
170:
152:
3929:
3818:
3795:
3693:
3387:
3280:
3218:
3200:
2292:
or modern actively predatory arthropods. Additionally, the chelicerae of
1434:
1413:
1393:
1372:
1266:
1237:
1117:
680:
610:
582:
508:
465:
225:
45:
1332:, might have rivalled the pterygotids in weight, if not surpassed them.
3962:
3784:
3770:
3749:
3742:
3707:
3548:
3236:
3227:
3176:
2968:
2939:
Romer, Alfred S. (1933). "Eurypterid Influence on Vertebrate History".
2770:
2651:
Treatise on Invertebrate Paleontology, Part P Arthropoda 2, Chelicerata
2554:
2393:
2248:
2236:
2230:
2157:
2065:
2047:
1997:
1346:
1305:
1215:
1164:
1155:
1087:
1066:
999:
872:
Erik N. Kjellesvig-Waering emended the family in 1951, when the genera
787:
676:
671:
651:
639:
625:
619:
560:
548:
535:
496:
490:
461:
437:
410:
405:
370:
330:
238:
164:
158:
126:
121:
90:
55:
1289:
577:, showcasing the distinct scale-like ornamentation of the pterygotids.
3861:
3845:
3835:
3194:
2224:
1315:
1241:
1168:
937:
845:
was proposed by Ferdinand Prantl and Alois Přibyl in 1948, retaining
755:
504:
426:
414:
215:
195:
95:
39:
3891:
1081:
958:
a member of the Pterygotidae once more. In 1974, Størmer raised the
585:, and other arthropods in general, pterygotid eurypterids possessed
3914:
3804:
3777:
2350:
1826:
1609:
1109:
1093:
770:
749:
688:
507:" with early vertebrates, that the evolution of heavy armor in the
85:
80:
65:
60:
50:
1038:
as previously thought, was the closest sister taxon of the group.
2885:"Distribution and dispersal history of Eurypterida (Chelicerata)"
2349:
correspond to strong puncturing and grasping abilities in extant
1270:
1193:
1130:
1057:, preserves a mixture of characteristics that are reminiscent of
606:
594:
590:
100:
75:
3949:
2516:
3188:
2825:
10.1666/pleo0022-3360(2007)081[0725:PEFTSV]2.0.CO;2
2184:
2169:
692:
614:
598:
469:
457:
205:
3145:
3100:
1076:
1007:
remains makes assignment to either impossible, and therefore,
2734:
as "winged fish", but there is no "fish" element in the name.
2592:
Braddy, Simon J.; Poschmann, Markus; Tetlie, O. Erik (2007).
1763:
is thought to represent the sister group to the pterygotids.
1262:
2995:
Verhandlungen des Naturwissenschaftlichen Vereins in Hamburg
896:
to the level of its own genus, recognizing two subgenera of
429:
to have ever lived with some members of the family, such as
1197:
991:
of a large pterygotid. The fossil likely belongs to either
988:
629:) and is indented (giving a bilobed appearance) in others (
2301:
suggests that it was not as active, nor as specialised as
546:
in age, ranged in size from quite small animals, such as
3025:
10.3374/0079-032X(2008)49[19:HEASCE]2.0.CO;2
974:
has later been recognized as representing a synonym of
3073:
10.1206/0003-0090(2004)285<0219:c>2.0.co;2
2790:. In World Spider Catalog. Natural History Museum Bern
2591:
2788:
A summary list of fossil spiders and their relatives
2360:
302:
1257:, and is indented (giving a bilobed appearance) in
589:bodies and jointed appendages (limbs) covered in a
3061:Bulletin of the American Museum of Natural History
2756:
2281:, though it was not as acute as the vision of the
2273:was similar to that of the more basal pterygotoid
3013:Bulletin of the Peabody Museum of Natural History
2893:Palaeogeography, Palaeoclimatology, Palaeoecology
2677:
2212:Restoration of various eurypterids discovered in
4016:
2786:Dunlop, J. A., Penney, D. & Jekel, D. 2018.
2594:"Giant claw reveals the largest ever arthropod"
735:The family Pterygotidae was erected in 1912 by
638:Like other chelicerates, pterygotids possessed
494:, and ambush predators and scavengers, such as
3058:
2882:
3161:
2989:Kraus, O., Brauckmann, C. (2003-08-26).
2878:
2876:
2874:
2806:
2487:Extinction and survival in the fossil record
2426:
2807:Ciurca, Samuel J.; Tetlie, O. Erik (2007).
2730:Note that this work incorrectly translates
1077:Potential influence in vertebrate evolution
3168:
3154:
2871:
1189:had to have been composed of four joints.
714:recognized that it was possible to divide
135:
111:
3126:
2720:
2619:
2553:
1053:The most primitive and basal pterygotid,
1011:is considered an unspecified pterygotid.
769:would also designated as containing two "
2587:
2585:
2583:
2581:
2579:
2577:
2575:
2573:
2333:. A significantly less active predator,
2207:
1740:
1339:
1288:
1208:
1145:
1080:
946:, previously designated as a species of
665:
566:
519:
2647:
1041:
884:were referred to their own family, the
417:. They were members of the superfamily
409:, meaning "winged one") is a family of
403:(the name deriving from the type genus
4017:
3096:
3094:
3092:
3090:
3010:
2512:
2510:
841:). A division into three subgenera of
661:
3896:
3895:
3149:
2938:
2934:
2932:
2930:
2802:
2800:
2798:
2796:
2782:
2780:
2648:Størmer, Leif (1955). "Merostomata".
2570:
2277:and more acute than the more derived
1736:
743:to constitute a group for the genera
732:) for species with a bilobed telson.
538:, which occur in strata ranging from
3004:
2752:
2750:
2748:
2746:
2744:
2742:
2740:
2673:
2671:
2669:
2667:
2665:
2663:
2661:
2643:
2641:
2639:
2422:
2420:
2418:
2416:
2414:
2412:
2410:
2408:
2152:Large angular denticle on the fixed
2069:(210 cm, 6 ft 11 in)
695:" by the quarrymen. When describing
658:, and other eurypterids in general.
482:, to active apex predators, such as
3087:
2507:
2051:(200 cm, 6 ft 7 in)
2026:(250 cm, 8 ft 2 in)
2001:(160 cm, 5 ft 3 in)
1915:(90 cm, 2 ft 11 in)
1830:(100 cm, 3 ft 3 in)
1141:
13:
2927:
2793:
2777:
2721:Murchison, Roderick Impey (1839).
2700:10.1111/j.1502-3931.1988.tb01746.x
2525:Journal of Vertebrate Paleontology
1958:(70 cm, 2 ft 4 in)
1865:(70 cm, 2 ft 4 in)
1751:, the most basal known pterygotid.
14:
4061:
2737:
2658:
2636:
2405:
1335:
970:to the level of separate genera.
3878:
3877:
3574:
2728:. Albemarle Street. p. 606.
2449:10.1111/j.1475-4983.2009.00907.x
2363:
182:
43:
3867:Timeline of eurypterid research
3175:
3052:
3039:
2983:
2847:
2384:Timeline of eurypterid research
2252:can be seen in the center-left.
2203:
2178:
2162:
2146:
1245:, where a flattened telson had
1136:
916:), as well as two subgenera of
4050:Prehistoric arthropod families
2714:
2471:
515:
413:, an extinct group of aquatic
144:Left to right, top to bottom:
1:
2546:10.1080/02724634.2019.1620247
2399:
1375:and creating the superfamily
1344:Illustration of a fossilized
16:Extinct family of eurypterids
4040:Llandovery first appearances
2914:10.1016/j.palaeo.2007.05.011
1284:
1175:would have three joints and
7:
2961:10.1126/science.78.2015.114
2356:
1354:
10:
4066:
4045:Early Devonian extinctions
1937:Erettopterus serricaudatus
1894:Erettopterus waylandsmithi
1369:Nestor Ivanovich Novojilov
801:into two other subgenera,
3904:
3875:
3854:
3828:
3794:
3664:
3621:
3583:
3572:
3534:
3516:
3498:
3470:
3459:
3431:
3413:
3395:
3384:
3352:
3329:
3306:
3288:
3277:
3269:List of eurypterid genera
3261:
3254:
3183:
2379:List of eurypterid genera
2062:
2048:Acutiramus macrophthalmus
2044:
2037:
2019:
2012:
1994:
1987:
1951:
1933:
1926:
1908:
1890:
1883:
1876:
1858:
1851:
1841:
1823:
1816:
1798:
1791:
1630:
1623:
1606:
1599:
1582:
1575:
1558:
1551:
1533:
1526:
1511:
1504:
1489:
1482:
1467:
1460:
1445:
1438:
1411:
1404:
1397:
1204:
1048:cosmopolitan distribution
825:) as a junior synonym of
722:into subgenera, erecting
386:
379:
325:
320:
301:
294:
179:Scientific classification
177:
165:Acutiramus macrophthalmus
143:
134:
119:
110:
23:
1940:(60 cm, 2 ft)
1897:(60 cm, 2 ft)
1862:Ciurcopterus ventricosus
1805:(20 cm, 8 in)
1780:("phyletic gigantism").
1123:evolution of proper jaws
605:(sections); the frontal
171:Ciurcopterus ventricosus
2883:O. Erik Tetlie (2007).
2813:Journal of Paleontology
2759:Journal of Paleontology
2491:Systematics Association
2023:Jaekelopterus rhenaniae
1912:Erettopterus osiliensis
1300:Jaekelopterus rhenaniae
874:Hastimima, Hughmilleria
691:, were referred to as "
574:Erettopterus osiliensis
555:Jaekelopterus rhenaniae
425:were the largest known
147:Jaekelopterus rhenaniae
3119:10.1098/rsbl.2015.0564
2612:10.1098/rsbl.2007.0491
2253:
2187:with a posterior spine
1752:
1359:Since its creation by
1351:
1294:
1220:
1160:
1098:
1016:Pterygotus ventricosus
833:) and not recognizing
684:
578:
531:
454:worldwide distribution
3997:Paleobiology Database
2211:
1802:Hughmilleria socialis
1773:Hughmilleria socialis
1744:
1343:
1292:
1212:
1153:(cheliceral claw) of
1149:
1084:
994:Erettopterus marstoni
869:) to subgenus level.
861:) but also restoring
669:
609:(head) and posterior
570:
523:
3045:Novojilov, N. 1962:
2493:. pp. 171–209.
2066:Acutiramus bohemicus
1955:Erettopterus bilobus
1306:Acutiramus bohemicus
1247:convergently evolved
1042:Evolutionary history
561:Acutiramus bohemicus
153:Erettopterus bilobus
127:Acutiramus cummingsi
2953:1933Sci....78..114R
2906:2007PPP...252..557T
2692:1988Letha..21...13P
2538:2019JVPal..39E0247O
2441:2009Palgy..52.1141T
2371:Paleontology portal
2172:, undifferentiated
1998:Pterygotus anglicus
1227:and by the derived
1000:Pterygotus arcuatus
712:John William Salter
662:History of research
307:Pterygotus anglicus
159:Pterygotus anglicus
3397:Onychopterelloidea
2254:
1827:Slimonia acuminata
1768:Slimonia acuminata
1753:
1745:Reconstruction of
1737:Internal phylogeny
1352:
1303:at 2.5 metres and
1295:
1221:
1161:
1099:
685:
579:
571:Fossil segment of
558:at 2.5 metres and
549:Acutiramus floweri
532:
524:Reconstruction of
4012:
4011:
3984:Open Tree of Life
3898:Taxon identifiers
3889:
3888:
3570:
3569:
3566:
3565:
3562:
3561:
3518:Adelophthalmoidea
3500:Waeringopteroidea
3472:Carcinosomatoidea
3405:Onychopterellidae
3380:
3379:
3047:Order Eurypterida
2947:(2015): 114–117.
2500:978-0-19-857708-9
2200:
2199:
2141:
2140:
2132:
2131:
2123:
2122:
2114:
2113:
2105:
2104:
2096:
2095:
2087:
2086:
2078:
2077:
1976:
1975:
1967:
1966:
1733:
1732:
1724:
1723:
1715:
1714:
1706:
1705:
1697:
1696:
1688:
1687:
1679:
1678:
1670:
1669:
1661:
1660:
1652:
1651:
1643:
1642:
1536:Adelophthalmoidea
1514:Waeringopteroidea
1492:Carcinosomatoidea
1424:
1423:
1361:John Mason Clarke
737:John Mason Clarke
398:
397:
392:
290:
38:428.2–372.2
4057:
4035:Devonian animals
4030:Silurian animals
4005:
4004:
3992:
3991:
3979:
3978:
3966:
3965:
3953:
3952:
3940:
3939:
3938:
3925:
3924:
3923:
3893:
3892:
3881:
3880:
3855:Related articles
3812:Merostomichnites
3578:
3526:Adelophthalmidae
3508:Waeringopteridae
3480:Carcinosomatidae
3468:
3467:
3451:Strobilopteridae
3393:
3392:
3367:Hibbertopteridae
3316:Parastylonuridae
3286:
3285:
3259:
3258:
3170:
3163:
3156:
3147:
3146:
3141:
3140:
3130:
3098:
3085:
3084:
3056:
3050:
3043:
3037:
3036:
3008:
3002:
2987:
2981:
2980:
2936:
2925:
2924:
2922:
2916:. Archived from
2900:(3–4): 557–574.
2889:
2880:
2869:
2868:
2866:
2865:
2851:
2845:
2844:
2804:
2791:
2784:
2775:
2774:
2754:
2735:
2729:
2718:
2712:
2711:
2675:
2656:
2655:
2645:
2634:
2633:
2623:
2589:
2568:
2567:
2557:
2514:
2505:
2504:
2475:
2469:
2468:
2435:(5): 1141–1148.
2424:
2373:
2368:
2367:
2366:
2331:ecological niche
2188:
2182:
2176:
2166:
2160:
2150:
2040:
2039:
2015:
2014:
1990:
1989:
1929:
1928:
1886:
1885:
1879:
1878:
1854:
1853:
1844:
1843:
1819:
1818:
1794:
1793:
1784:
1783:
1626:
1625:
1602:
1601:
1578:
1577:
1554:
1553:
1529:
1528:
1507:
1506:
1485:
1484:
1463:
1462:
1448:Megalograptoidea
1441:
1440:
1407:
1406:
1400:
1399:
1390:
1389:
1365:Rudolf Ruedemann
1142:Cheliceral claws
741:Rudolf Ruedemann
699:itself in 1839,
390:
389:Jaekelopteridae
304:
281:
276:
263:
250:
237:
187:
186:
139:
115:
105:
42:
27:Temporal range:
21:
20:
4065:
4064:
4060:
4059:
4058:
4056:
4055:
4054:
4015:
4014:
4013:
4008:
4000:
3995:
3987:
3982:
3974:
3969:
3961:
3956:
3948:
3943:
3934:
3933:
3928:
3919:
3918:
3913:
3900:
3890:
3885:
3871:
3850:
3841:Chasmataspidida
3824:
3790:
3687:Campylocephalus
3660:
3617:
3579:
3558:
3544:Hughmilleriidae
3530:
3512:
3494:
3485:Megalograptidae
3461:
3455:
3441:Dolichopteridae
3427:
3415:Moselopteroidea
3409:
3386:
3376:
3362:Drepanopteridae
3348:
3344:Hardieopteridae
3331:Kokomopteroidea
3325:
3302:
3279:
3273:
3250:
3179:
3174:
3144:
3113:(8): 20150564.
3107:Biology Letters
3099:
3088:
3057:
3053:
3044:
3040:
3009:
3005:
2988:
2984:
2937:
2928:
2920:
2887:
2881:
2872:
2863:
2861:
2853:
2852:
2848:
2805:
2794:
2785:
2778:
2755:
2738:
2719:
2715:
2676:
2659:
2646:
2637:
2599:Biology Letters
2590:
2571:
2532:(3): e1620247.
2515:
2508:
2501:
2479:D. E. G. Briggs
2476:
2472:
2425:
2406:
2402:
2389:Hughmilleriidae
2369:
2364:
2362:
2359:
2206:
2201:
2192:
2191:
2183:
2179:
2167:
2163:
2151:
2147:
2142:
2133:
2124:
2115:
2106:
2097:
2088:
2079:
1977:
1968:
1739:
1734:
1725:
1716:
1707:
1698:
1689:
1680:
1671:
1662:
1653:
1644:
1586:Herefordopterus
1425:
1357:
1338:
1287:
1207:
1144:
1139:
1102:Alfred S. Romer
1085:Restoration of
1079:
1044:
1031:Herefordopterus
886:Hughmilleriidae
817:), designating
679:illustrated by
664:
656:Hughmilleriidae
581:Like all other
564:at 2.1 metres.
518:
476:group, such as
316:
310:
280:
274:
261:
248:
235:
181:
106:
104:
103:
98:
93:
88:
83:
78:
73:
68:
63:
58:
53:
48:
37:
36:
25:
17:
12:
11:
5:
4063:
4053:
4052:
4047:
4042:
4037:
4032:
4027:
4025:Pterygotioidea
4010:
4009:
4007:
4006:
3993:
3980:
3967:
3954:
3941:
3926:
3910:
3908:
3902:
3901:
3887:
3886:
3876:
3873:
3872:
3870:
3869:
3864:
3858:
3856:
3852:
3851:
3849:
3848:
3843:
3838:
3832:
3830:
3829:Related groups
3826:
3825:
3823:
3822:
3815:
3808:
3800:
3798:
3792:
3791:
3789:
3788:
3781:
3774:
3767:
3760:
3757:Onychopterella
3753:
3746:
3739:
3732:
3725:
3718:
3715:Hibbertopterus
3711:
3704:
3697:
3690:
3683:
3676:
3673:Adelophthalmus
3668:
3666:
3665:Notable genera
3662:
3661:
3659:
3658:
3653:
3648:
3643:
3638:
3633:
3627:
3625:
3619:
3618:
3616:
3615:
3610:
3605:
3600:
3595:
3589:
3587:
3581:
3580:
3573:
3571:
3568:
3567:
3564:
3563:
3560:
3559:
3557:
3556:
3551:
3546:
3540:
3538:
3536:Pterygotioidea
3532:
3531:
3529:
3528:
3522:
3520:
3514:
3513:
3511:
3510:
3504:
3502:
3496:
3495:
3493:
3492:
3487:
3482:
3476:
3474:
3465:
3463:Diploperculata
3457:
3456:
3454:
3453:
3448:
3443:
3437:
3435:
3429:
3428:
3426:
3425:
3423:Moselopteridae
3419:
3417:
3411:
3410:
3408:
3407:
3401:
3399:
3390:
3382:
3381:
3378:
3377:
3375:
3374:
3369:
3364:
3358:
3356:
3350:
3349:
3347:
3346:
3341:
3339:Kokomopteridae
3335:
3333:
3327:
3326:
3324:
3323:
3318:
3312:
3310:
3304:
3303:
3301:
3300:
3294:
3292:
3290:Rhenopteroidea
3283:
3275:
3274:
3272:
3271:
3265:
3263:
3256:
3252:
3251:
3249:
3248:
3239:
3230:
3221:
3212:
3203:
3197:
3191:
3184:
3181:
3180:
3173:
3172:
3165:
3158:
3150:
3143:
3142:
3086:
3051:
3038:
3003:
2982:
2926:
2923:on 2011-07-18.
2870:
2859:www.palass.org
2846:
2819:(4): 725–736.
2792:
2776:
2765:(2): 331–361.
2736:
2713:
2657:
2635:
2606:(1): 106–109.
2569:
2506:
2499:
2470:
2403:
2401:
2398:
2397:
2396:
2391:
2386:
2381:
2375:
2374:
2358:
2355:
2283:apex predators
2205:
2202:
2198:
2197:
2194:
2193:
2190:
2189:
2177:
2161:
2144:
2143:
2139:
2138:
2135:
2134:
2130:
2129:
2126:
2125:
2121:
2120:
2117:
2116:
2112:
2111:
2108:
2107:
2103:
2102:
2099:
2098:
2094:
2093:
2090:
2089:
2085:
2084:
2081:
2080:
2076:
2075:
2072:
2071:
2061:
2058:
2057:
2054:
2053:
2043:
2038:
2036:
2033:
2032:
2029:
2028:
2018:
2013:
2011:
2008:
2007:
2004:
2003:
1993:
1988:
1986:
1983:
1982:
1979:
1978:
1974:
1973:
1970:
1969:
1965:
1964:
1961:
1960:
1950:
1947:
1946:
1943:
1942:
1932:
1927:
1925:
1922:
1921:
1918:
1917:
1907:
1904:
1903:
1900:
1899:
1889:
1884:
1882:
1877:
1875:
1872:
1871:
1868:
1867:
1857:
1852:
1850:
1842:
1840:
1837:
1836:
1833:
1832:
1822:
1817:
1815:
1812:
1811:
1808:
1807:
1797:
1792:
1790:
1788:Pterygotioidea
1782:
1738:
1735:
1731:
1730:
1727:
1726:
1722:
1721:
1718:
1717:
1713:
1712:
1709:
1708:
1704:
1703:
1700:
1699:
1695:
1694:
1691:
1690:
1686:
1685:
1682:
1681:
1677:
1676:
1673:
1672:
1668:
1667:
1664:
1663:
1659:
1658:
1655:
1654:
1650:
1649:
1646:
1645:
1641:
1640:
1637:
1636:
1629:
1624:
1622:
1619:
1618:
1615:
1614:
1605:
1600:
1598:
1595:
1594:
1591:
1590:
1581:
1576:
1574:
1571:
1570:
1567:
1566:
1557:
1552:
1550:
1548:Pterygotioidea
1544:
1543:
1540:
1539:
1532:
1527:
1525:
1522:
1521:
1518:
1517:
1510:
1505:
1503:
1500:
1499:
1496:
1495:
1488:
1483:
1481:
1478:
1477:
1474:
1473:
1466:
1461:
1459:
1456:
1455:
1452:
1451:
1444:
1439:
1437:
1431:
1430:
1427:
1426:
1422:
1421:
1418:
1417:
1410:
1405:
1403:
1398:
1396:
1388:
1377:Pterygotioidea
1356:
1353:
1337:
1336:Classification
1334:
1330:Hibbertopterus
1286:
1283:
1233:Hibbertopterus
1229:hibbertopterid
1206:
1203:
1143:
1140:
1138:
1135:
1078:
1075:
1071:Pterygotioidea
1043:
1040:
663:
660:
517:
514:
419:Pterygotioidea
396:
395:
394:
393:
384:
383:
377:
376:
375:
374:
366:
358:
350:
342:
334:
323:
322:
318:
317:
311:
299:
298:
292:
291:
272:
268:
267:
265:Pterygotioidea
259:
255:
254:
252:Diploperculata
246:
242:
241:
233:
229:
228:
223:
219:
218:
213:
209:
208:
203:
199:
198:
193:
189:
188:
175:
174:
141:
140:
132:
131:
117:
116:
108:
107:
99:
94:
89:
84:
79:
74:
69:
64:
59:
54:
49:
44:
26:
15:
9:
6:
4:
3:
2:
4062:
4051:
4048:
4046:
4043:
4041:
4038:
4036:
4033:
4031:
4028:
4026:
4023:
4022:
4020:
4003:
3998:
3994:
3990:
3985:
3981:
3977:
3972:
3968:
3964:
3959:
3955:
3951:
3946:
3942:
3937:
3931:
3927:
3922:
3916:
3912:
3911:
3909:
3907:
3903:
3899:
3894:
3884:
3874:
3868:
3865:
3863:
3860:
3859:
3857:
3853:
3847:
3844:
3842:
3839:
3837:
3834:
3833:
3831:
3827:
3821:
3820:
3816:
3814:
3813:
3809:
3807:
3806:
3802:
3801:
3799:
3797:
3793:
3787:
3786:
3782:
3780:
3779:
3775:
3773:
3772:
3768:
3766:
3765:
3764:Pentecopterus
3761:
3759:
3758:
3754:
3752:
3751:
3747:
3745:
3744:
3740:
3738:
3737:
3736:Megalograptus
3733:
3731:
3730:
3729:Jaekelopterus
3726:
3724:
3723:
3719:
3717:
3716:
3712:
3710:
3709:
3705:
3703:
3702:
3701:Drepanopterus
3698:
3696:
3695:
3691:
3689:
3688:
3684:
3682:
3681:
3680:Brachyopterus
3677:
3675:
3674:
3670:
3669:
3667:
3663:
3657:
3656:South America
3654:
3652:
3649:
3647:
3646:North America
3644:
3642:
3639:
3637:
3634:
3632:
3629:
3628:
3626:
3624:
3620:
3614:
3611:
3609:
3608:Carboniferous
3606:
3604:
3601:
3599:
3596:
3594:
3591:
3590:
3588:
3586:
3585:Geochronology
3582:
3577:
3555:
3552:
3550:
3547:
3545:
3542:
3541:
3539:
3537:
3533:
3527:
3524:
3523:
3521:
3519:
3515:
3509:
3506:
3505:
3503:
3501:
3497:
3491:
3488:
3486:
3483:
3481:
3478:
3477:
3475:
3473:
3469:
3466:
3464:
3458:
3452:
3449:
3447:
3444:
3442:
3439:
3438:
3436:
3434:
3433:Eurypteroidea
3430:
3424:
3421:
3420:
3418:
3416:
3412:
3406:
3403:
3402:
3400:
3398:
3394:
3391:
3389:
3383:
3373:
3372:Mycteroptidae
3370:
3368:
3365:
3363:
3360:
3359:
3357:
3355:
3354:Mycteropoidea
3351:
3345:
3342:
3340:
3337:
3336:
3334:
3332:
3328:
3322:
3319:
3317:
3314:
3313:
3311:
3309:
3308:Stylonuroidea
3305:
3299:
3298:Rhenopteridae
3296:
3295:
3293:
3291:
3287:
3284:
3282:
3276:
3270:
3267:
3266:
3264:
3260:
3257:
3253:
3247:
3246:Sclerophorata
3243:
3240:
3238:
3234:
3231:
3229:
3225:
3222:
3220:
3216:
3213:
3211:
3210:Euchelicerata
3207:
3204:
3202:
3198:
3196:
3192:
3190:
3186:
3185:
3182:
3178:
3171:
3166:
3164:
3159:
3157:
3152:
3151:
3148:
3138:
3134:
3129:
3124:
3120:
3116:
3112:
3108:
3104:
3097:
3095:
3093:
3091:
3082:
3078:
3074:
3070:
3066:
3062:
3055:
3048:
3042:
3034:
3030:
3026:
3022:
3018:
3014:
3007:
3000:
2996:
2992:
2986:
2978:
2974:
2970:
2966:
2962:
2958:
2954:
2950:
2946:
2942:
2935:
2933:
2931:
2919:
2915:
2911:
2907:
2903:
2899:
2895:
2894:
2886:
2879:
2877:
2875:
2860:
2856:
2850:
2842:
2838:
2834:
2830:
2826:
2822:
2818:
2814:
2810:
2803:
2801:
2799:
2797:
2789:
2783:
2781:
2772:
2768:
2764:
2760:
2753:
2751:
2749:
2747:
2745:
2743:
2741:
2733:
2727:
2726:
2717:
2709:
2705:
2701:
2697:
2693:
2689:
2685:
2681:
2674:
2672:
2670:
2668:
2666:
2664:
2662:
2654:. p. 23.
2653:
2652:
2644:
2642:
2640:
2631:
2627:
2622:
2617:
2613:
2609:
2605:
2601:
2600:
2595:
2588:
2586:
2584:
2582:
2580:
2578:
2576:
2574:
2565:
2561:
2556:
2551:
2547:
2543:
2539:
2535:
2531:
2527:
2526:
2521:
2513:
2511:
2502:
2496:
2492:
2488:
2484:
2480:
2474:
2466:
2462:
2458:
2454:
2450:
2446:
2442:
2438:
2434:
2430:
2429:Palaeontology
2423:
2421:
2419:
2417:
2415:
2413:
2411:
2409:
2404:
2395:
2392:
2390:
2387:
2385:
2382:
2380:
2377:
2376:
2372:
2361:
2354:
2352:
2347:
2343:
2342:Jaekelopterus
2338:
2336:
2332:
2328:
2324:
2323:Jaekelopterus
2320:
2315:
2310:
2308:
2307:Jaekelopterus
2304:
2299:
2295:
2291:
2287:
2286:Jaekelopterus
2284:
2280:
2276:
2272:
2267:
2264:
2263:compound eyes
2259:
2258:visual acuity
2251:
2250:
2245:
2244:
2239:
2238:
2233:
2232:
2227:
2226:
2221:
2220:
2219:Dolichopterus
2215:
2210:
2196:
2195:
2186:
2181:
2175:
2171:
2165:
2159:
2155:
2149:
2145:
2137:
2136:
2128:
2127:
2119:
2118:
2110:
2109:
2101:
2100:
2092:
2091:
2083:
2082:
2074:
2073:
2070:
2068:
2067:
2060:
2059:
2056:
2055:
2052:
2050:
2049:
2042:
2041:
2035:
2034:
2031:
2030:
2027:
2025:
2024:
2017:
2016:
2010:
2009:
2006:
2005:
2002:
2000:
1999:
1992:
1991:
1985:
1984:
1981:
1980:
1972:
1971:
1963:
1962:
1959:
1957:
1956:
1949:
1948:
1945:
1944:
1941:
1939:
1938:
1931:
1930:
1924:
1923:
1920:
1919:
1916:
1914:
1913:
1906:
1905:
1902:
1901:
1898:
1896:
1895:
1888:
1887:
1881:
1880:
1874:
1873:
1870:
1869:
1866:
1864:
1863:
1856:
1855:
1849:
1846:
1845:
1839:
1838:
1835:
1834:
1831:
1829:
1828:
1821:
1820:
1814:
1813:
1810:
1809:
1806:
1804:
1803:
1796:
1795:
1789:
1786:
1785:
1781:
1779:
1775:
1774:
1769:
1764:
1762:
1758:
1757:Jaekelopterus
1750:
1749:
1743:
1729:
1728:
1720:
1719:
1711:
1710:
1702:
1701:
1693:
1692:
1684:
1683:
1675:
1674:
1666:
1665:
1657:
1656:
1648:
1647:
1639:
1638:
1635:
1634:
1628:
1627:
1621:
1620:
1617:
1616:
1613:
1612:
1611:
1604:
1603:
1597:
1596:
1593:
1592:
1589:
1588:
1587:
1580:
1579:
1573:
1572:
1569:
1568:
1565:
1564:
1563:
1556:
1555:
1549:
1546:
1545:
1542:
1541:
1538:
1537:
1531:
1530:
1524:
1523:
1520:
1519:
1516:
1515:
1509:
1508:
1502:
1501:
1498:
1497:
1494:
1493:
1487:
1486:
1480:
1479:
1476:
1475:
1472:
1471:
1470:Eurypteroidea
1465:
1464:
1458:
1457:
1454:
1453:
1450:
1449:
1443:
1442:
1436:
1433:
1432:
1429:
1428:
1420:
1419:
1416:
1415:
1409:
1408:
1402:
1401:
1395:
1392:
1391:
1387:
1384:
1380:
1378:
1374:
1370:
1366:
1362:
1349:
1348:
1342:
1333:
1331:
1325:
1323:
1322:
1317:
1313:
1308:
1307:
1302:
1301:
1291:
1282:
1280:
1274:
1272:
1268:
1264:
1260:
1256:
1252:
1248:
1244:
1243:
1239:
1235:
1234:
1230:
1226:
1218:
1217:
1211:
1202:
1199:
1195:
1190:
1187:
1183:
1178:
1174:
1170:
1166:
1158:
1157:
1152:
1148:
1134:
1132:
1126:
1124:
1119:
1114:
1111:
1107:
1106:Late Silurian
1103:
1096:
1095:
1090:
1089:
1083:
1074:
1073:superfamily.
1072:
1068:
1064:
1060:
1056:
1051:
1049:
1039:
1037:
1033:
1032:
1027:
1023:
1022:
1017:
1012:
1010:
1009:Necrogammarus
1006:
1005:Necrogammarus
1002:
1001:
996:
995:
990:
986:
985:
984:Necrogammarus
979:
977:
973:
972:Truncatiramus
969:
968:Truncatiramus
965:
961:
957:
956:Jaekelopterus
953:
952:Jaekelopterus
949:
945:
944:Jaekelopterus
941:
939:
935:
934:Truncatiramus
931:
927:
923:
919:
915:
911:
907:
903:
899:
895:
891:
888:, which left
887:
883:
879:
875:
870:
868:
864:
860:
856:
852:
848:
844:
840:
836:
832:
828:
824:
820:
816:
812:
808:
804:
800:
796:
795:
790:
789:
784:
780:
776:
772:
768:
764:
763:
758:
757:
752:
751:
746:
742:
738:
733:
731:
730:
725:
721:
717:
713:
709:
704:
702:
701:Louis Agassiz
698:
694:
690:
682:
678:
674:
673:
668:
659:
657:
653:
649:
645:
641:
636:
634:
633:
628:
627:
622:
621:
616:
612:
608:
604:
600:
596:
592:
588:
584:
576:
575:
569:
565:
563:
562:
557:
556:
551:
550:
545:
544:Late Devonian
541:
540:Late Silurian
537:
529:
528:
527:Jaekelopterus
522:
513:
510:
506:
501:
499:
498:
493:
492:
487:
486:
485:Jaekelopterus
481:
480:
473:
471:
467:
463:
459:
455:
450:
448:
447:Late Devonian
444:
443:Late Silurian
440:
439:
434:
433:
432:Jaekelopterus
428:
424:
420:
416:
412:
408:
407:
402:
391:Størmer, 1974
388:
387:
385:
382:
378:
373:
372:
367:
365:
364:
363:Necrogammarus
359:
357:
356:
355:Jaekelopterus
351:
349:
348:
343:
341:
340:
335:
333:
332:
327:
326:
324:
319:
314:
309:
308:
300:
297:
293:
288:
284:
279:
273:
270:
269:
266:
260:
258:Superfamily:
257:
256:
253:
247:
244:
243:
240:
234:
231:
230:
227:
224:
221:
220:
217:
214:
211:
210:
207:
204:
201:
200:
197:
194:
191:
190:
185:
180:
176:
173:
172:
167:
166:
161:
160:
155:
154:
149:
148:
142:
138:
133:
129:
128:
123:
118:
114:
109:
102:
97:
92:
87:
82:
77:
72:
67:
62:
57:
52:
47:
41:
34:
33:Late Devonian
30:
29:Late Silurian
22:
19:
3936:Pterygotidae
3906:Pterygotidae
3905:
3817:
3810:
3803:
3783:
3776:
3769:
3762:
3755:
3748:
3741:
3734:
3727:
3722:Hughmilleria
3720:
3713:
3706:
3699:
3692:
3685:
3678:
3671:
3554:Pterygotidae
3553:
3490:Mixopteridae
3446:Eurypteridae
3321:Stylonuridae
3241:
3232:
3223:
3214:
3205:
3110:
3106:
3064:
3060:
3054:
3046:
3041:
3016:
3012:
3006:
2998:
2994:
2985:
2944:
2940:
2918:the original
2897:
2891:
2862:. Retrieved
2858:
2849:
2816:
2812:
2762:
2758:
2731:
2723:
2716:
2686:(1): 13–27.
2683:
2679:
2650:
2603:
2597:
2529:
2523:
2486:
2483:R. A. Fortey
2473:
2432:
2428:
2345:
2341:
2339:
2334:
2326:
2322:
2318:
2313:
2312:The eyes of
2311:
2306:
2302:
2298:Erettopterus
2297:
2294:Erettopterus
2293:
2289:
2285:
2278:
2274:
2271:Erettopterus
2270:
2268:
2255:
2247:
2243:Hughmilleria
2241:
2235:
2229:
2223:
2217:
2216:, including
2204:Paleoecology
2180:
2164:
2148:
2064:
2063:
2046:
2045:
2021:
2020:
1996:
1995:
1953:
1952:
1935:
1934:
1910:
1909:
1892:
1891:
1860:
1859:
1848:Pterygotidae
1847:
1825:
1824:
1800:
1799:
1771:
1767:
1765:
1760:
1756:
1754:
1748:Ciurcopterus
1746:
1633:Pterygotidae
1632:
1631:
1608:
1607:
1584:
1583:
1562:Hughmilleria
1560:
1559:
1534:
1512:
1490:
1468:
1446:
1412:
1385:
1381:
1358:
1345:
1329:
1326:
1321:Arthropleura
1319:
1304:
1298:
1296:
1278:
1275:
1259:Erettopterus
1258:
1254:
1250:
1240:
1231:
1224:
1222:
1214:
1191:
1186:Erettopterus
1185:
1181:
1177:Erettopterus
1176:
1172:
1162:
1154:
1137:Paleobiology
1127:
1115:
1100:
1092:
1086:
1062:
1058:
1055:Ciurcopterus
1054:
1052:
1045:
1036:Hughmilleria
1035:
1029:
1025:
1021:Ciurcopterus
1019:
1015:
1013:
1008:
1004:
998:
992:
982:
980:
976:Erettopterus
975:
971:
967:
963:
959:
955:
951:
947:
943:
942:
933:
929:
926:Erettopterus
925:
921:
918:Erettopterus
917:
913:
909:
905:
901:
897:
894:Erettopterus
893:
889:
881:
878:Grossopterus
877:
873:
871:
866:
862:
858:
854:
851:Erettopterus
850:
846:
842:
838:
834:
830:
826:
822:
818:
815:Erettopterus
814:
810:
806:
802:
798:
797:, and split
794:Grossopterus
792:
786:
782:
778:
774:
766:
762:Hughmilleria
760:
754:
748:
744:
734:
729:Erettopterus
727:
723:
719:
715:
707:
705:
696:
686:
670:
648:pterygotioid
637:
632:Erettopterus
630:
624:
618:
593:composed of
583:chelicerates
580:
572:
559:
553:
547:
533:
525:
509:ostracoderms
502:
495:
489:
483:
479:Erettopterus
477:
474:
451:
436:
430:
422:
404:
401:Pterygotidae
400:
399:
369:
361:
353:
347:Erettopterus
345:
339:Ciurcopterus
337:
329:
305:
296:Type species
278:Pterygotidae
277:
245:Infraorder:
169:
163:
157:
151:
145:
125:
24:Pterygotidae
18:
3930:Wikispecies
3819:Palmichnium
3796:Ichnogenera
3694:Carcinosoma
3388:Eurypterina
3281:Stylonurina
3219:Prosomapoda
3201:Chelicerata
3199:Subphylum:
3177:Eurypterids
3067:: 219–237.
2555:10784/26939
1778:Cope's rule
1435:Eurypterina
1414:Stylonurina
1394:Eurypterida
1373:Eurypterina
1267:opisthosoma
1238:mycteroptid
1169:xiphosurans
1165:crustaceans
1069:within the
681:Joseph Smit
677:eurypterids
611:opisthosoma
536:eurypterids
534:Pterygotid
516:Description
466:common name
423:Pterygotids
411:eurypterids
239:Eurypterida
226:Chelicerata
222:Subphylum:
4019:Categories
3785:Stylonurus
3771:Pterygotus
3750:Mixopterus
3743:Megarachne
3708:Eurypterus
3593:Ordovician
3549:Slimonidae
3460:Infraorder
3237:Dekatriata
3228:Planaterga
3195:Arthropoda
2864:2018-01-14
2732:Pterygotus
2725:Formations
2400:References
2394:Slimonidae
2346:Pterygotus
2335:Acutiramus
2327:Acutiramus
2319:Acutiramus
2314:Acutiramus
2303:Pterygotus
2290:Pterygotus
2279:Acutiramus
2249:Pterygotus
2237:Eurypterus
2231:Stylonurus
2158:chelicerae
1347:Acutiramus
1255:Acutiramus
1251:Pterygotus
1216:Pterygotus
1213:Telson of
1182:Acutiramus
1173:Pterygotus
1156:Pterygotus
1118:freshwater
1088:Pterygotus
1067:Slimonidae
964:Acutiramus
962:subgenera
960:Pterygotus
948:Pterygotus
914:Acutiramus
906:Pterygotus
898:Pterygotus
890:Pterygotus
867:Acutiramus
859:Pterygotus
843:Pterygotus
839:Acutiramus
835:Pterygotus
831:Pterygotus
827:Pterygotus
823:Curviramus
819:Pterygotus
811:Pterygotus
807:Pterygotus
803:Pterygotus
799:Pterygotus
788:Acutiramus
783:Pterygotus
779:Curviramus
775:Pterygotus
767:Pterygotus
745:Pterygotus
724:Pterygotus
720:Pterygotus
716:Pterygotus
708:Pterygotus
697:Pterygotus
675:and other
672:Pterygotus
652:Slimonidae
650:families,
640:chelicerae
626:Acutiramus
620:Pterygotus
497:Acutiramus
491:Pterygotus
462:chelicerae
438:Acutiramus
427:arthropods
415:arthropods
406:Pterygotus
371:Pterygotus
331:Acutiramus
216:Arthropoda
3862:Metastoma
3846:Xiphosura
3836:Arachnida
3623:Geography
3187:Kingdom:
3019:: 19–99.
2841:140668235
2833:0022-3360
2708:1502-3931
2564:198237241
2457:1475-4983
2351:scorpions
2225:Eusarcana
2174:denticles
1316:sternites
1312:stergites
1285:Gigantism
1242:Hastimima
1014:In 2009,
938:metastoma
771:subgenera
756:Hastimima
693:Seraphims
587:segmented
505:arms race
470:Seraphims
287:Ruedemann
202:Kingdom:
196:Eukaryota
122:chelicera
3921:Q7257012
3915:Wikidata
3883:Category
3805:Arcuites
3778:Slimonia
3603:Devonian
3598:Silurian
3385:Suborder
3278:Suborder
3255:Taxonomy
3193:Phylum:
3189:Animalia
3137:26289442
3081:73556985
3033:85862868
2977:17749819
2630:18029297
2465:84268058
2357:See also
2275:Slimonia
2214:New York
2168:Bilobed
1761:Slimonia
1610:Slimonia
1355:Taxonomy
1271:apodemes
1225:Slimonia
1110:Devonian
1094:Birkenia
1091:hunting
1063:Slimonia
1059:Slimonia
1026:Slimonia
882:Slimonia
750:Slimonia
689:Scotland
683:in 1896.
595:proteins
381:Synonyms
271:Family:
212:Phylum:
206:Animalia
192:Domain:
3989:5128472
3963:3255172
3950:4305745
3651:Oceania
3613:Permian
3128:4571687
2997:.
2993:.
2969:1660350
2949:Bibcode
2941:Science
2902:Bibcode
2771:1301554
2688:Bibcode
2680:Lethaia
2621:2412931
2534:Bibcode
2437:Bibcode
2156:of the
1194:prosoma
1131:Permian
607:prosoma
603:tagmata
591:cuticle
458:telsons
321:Genera
313:Agassiz
232:Order:
120:Fossil
4002:303383
3976:104651
3641:Europe
3631:Africa
3262:Genera
3135:
3125:
3079:
3031:
2975:
2967:
2839:
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2769:
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2463:
2455:
2185:Telson
2170:telson
1363:&
1279:et al.
1263:whales
1205:Telson
1028:, not
928:) and
908:) and
853:) and
809:) and
781:) and
739:&
644:chelae
615:telson
599:chitin
315:, 1844
289:, 1912
285:&
283:Clarke
3971:IRMNG
3242:Clade
3233:Clade
3224:Clade
3215:Clade
3206:Clade
3077:S2CID
3029:S2CID
2965:JSTOR
2921:(PDF)
2888:(PDF)
2837:S2CID
2767:JSTOR
2560:S2CID
2461:S2CID
2340:Both
2154:ramus
1198:crabs
1151:Chela
3958:GBIF
3636:Asia
3133:PMID
2973:PMID
2829:ISSN
2704:ISSN
2626:PMID
2495:ISBN
2453:ISSN
2344:and
2288:and
2240:and
1770:and
1314:and
1253:and
1236:and
1184:and
1167:and
1108:and
989:palp
966:and
880:and
759:and
654:and
623:and
597:and
488:and
435:and
46:PreꞒ
3945:EoL
3123:PMC
3115:doi
3069:doi
3065:285
3021:doi
2957:doi
2910:doi
2898:252
2821:doi
2696:doi
2616:PMC
2608:doi
2550:hdl
2542:doi
2445:doi
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