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245:
These irregular sea urchins are characterized by a particularly marked bilateral symmetry, including for the apical system, which is highly elongated. In some contemporary abyssal groups such as
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253:. The anus (periproct) has migrated towards the periphery of the test. The plastron is never amphisternous.
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249:, some species are even bottle-shaped. The mouth (peristome) does not contain an
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305:This order seems to have appeared at the lower
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482:Saucède, Dudicourt & Courville, 2012
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894:1A780AA7-0020-7EAE-3456-01171EBB8A27
855:23d1ca2c-f1ee-4868-b9bf-ba4f44dbd848
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13:
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14:
1016:
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691:World Register of Marine Species
319:World Register of Marine Species
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258:
122:
32:
1:
638:
953:. You can help Knowledge by
7:
558:(Smith & Jeffery, 2000)
210:Durham & Melville, 1957
10:
1021:
932:
710:
687:World Echinoidea Database
582:Foster & Philip, 1978
518:Foster & Philip, 1978
220:is an order of irregular
119:Scientific classification
117:
108:
99:
23:
398:Smith & Wright, 2003
681:Kroh A, Mooi R (eds.).
268:Hemipneustes pyrenaicus
30:Early Cretaceous–recent
676:Natural History Museum
527:Mooi & David, 1996
242:
238:Ceratophysa ceratopyga
945:This article about a
876:Paleobiology Database
235:
241:by A. Agassiz (1881)
16:Order of sea urchins
293:Echinosigra amphora
251:Aristotle's lantern
111:Pourtalesia wandeli
660:Echinoid Directory
394:Plesiohemipneustes
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863:Open Tree of Life
704:Taxon identifiers
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457:Echinocorythidae
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362:L. Agassiz, 1835
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339:L. Agassiz, 1835
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313:List of families
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27:Temporal range:
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618:(Lambert, 1922)
615:Stenonasteridae
506:Carnarechinidae
500:Mortensen, 1907
350:(Lambert, 1917)
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228:Characteristics
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683:"Holasteroida"
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656:"Holasteroida"
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441:
435:Cardiasteridae
419:Meridosternata
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386:Gauthier, 1889
377:
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347:Hemipneustidae
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298:Pourtalesiidae
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630:Lambert, 1922
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590:Pseudholaster
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438:Lambert, 1917
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428:Cardiasterina
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422:(Lovén, 1883)
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382:Opisopneustes
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374:Jeffery, 1997
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317:According to
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36:
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19:
1000:Holasteroida
955:expanding it
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741:Holasteroida
712:Holasteroida
711:
686:
672:Holasteroida
659:
624:
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588:
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545:Duncan, 1889
515:Corystusidae
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470:Pictet, 1857
467:Holasteridae
460:Wright, 1857
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358:Hemipneustes
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327:Disasteridae
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218:Holasteroida
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206:Holasteroida
205:
196:Atelostomata
192:Superorder:
182:Infraclass:
176:Euechinoidea
109:
24:Holasteroida
18:
801:iNaturalist
626:Stenonaster
606:Pomel, 1883
594:Pomel, 1883
578:Giraliaster
542:Urechinidae
489:Infraorder
426:Infraorder
410:Pomel, 1883
406:Toxopatagus
265:Fossile of
222:sea urchins
186:Irregularia
994:Categories
947:sea urchin
639:References
602:Taphraster
566:Eoholaster
497:Calymnidae
491:Urechinina
330:Gras, 1848
307:Cretaceous
172:Subclass:
166:Echinoidea
727:Q15089970
478:Salvaster
417:Suborder
325:† Family
321: :
142:Kingdom:
136:Eukaryota
721:Wikidata
370:Medjesia
336:Disaster
334:genus †
152:Phylum:
146:Animalia
132:Domain:
904:5983577
793:5964522
780:4711644
674:at the
613:Family
553:Family
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513:Family
504:Family
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465:Family
455:Family
443:Family
433:Family
345:Family
202:Order:
162:Class:
917:160733
901:uBio:
868:574937
852:NZOR:
845:327712
806:152893
754:531892
623:genus
599:genus
587:genus
575:genus
563:genus
475:Genus
403:genus
391:genus
379:genus
367:genus
355:genus
949:is a
912:WoRMS
889:Plazi
881:33281
819:12323
814:IRMNG
767:8ZXGY
951:stub
840:NCBI
788:GBIF
749:BOLD
35:PreꞒ
827:NBN
775:EoL
762:CoL
736:AFD
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85:Pg
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296:(
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271:(
90:N
80:K
75:J
70:T
65:P
60:C
55:D
50:S
45:O
40:Ꞓ
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