143:
125:
104:
339:
443:
is not adapted for a sediment-dwelling lifestyle as seen in the modern horseshoe crab. Under the questionable 12-legged interpretation, the legs with snow-shoe-like terminations instead of chela are also more adapted for walking on fine-grained surface instead of searching food items beneath the
358:
and pairs of well-developed, 8-segmented walking legs. Each of the distal leg podomeres (segmental units) bore numerous spines-like projections, forming a snow-shoe-like termination. The opisthosoma possess (possibly 6) pairs of opercula with
403:
was originally described as ten-legged like extant horseshoe crab; Selden, Lamsdell & Qi (2015) noted that the structures previously identified as distal regions of walking legs may be in fact leg-like exopods like those of
374:
is unusual in having 6 pairs of walking legs instead of 5 or less like those of other euchelicerates. The additional 6th leg pair was regarded to be originated from somite 7 (1st opisthosomal segment), thus
478:
Weinberginidae, an interpretation which is not recovered by later phylogenetic analysis. After the revision of relationship between synziphosurines and other euchelicerates done by
Lamsdell 2013,
331:
that possess blunt tergopleurae (lateral extension) and axial nodes. However, the opisthosoma is most likely 11-segmented in origin, with the first segment being highly reduced (a
960:
Bicknell, Russell D. C.; Lustri, Lorenzo; Brougham, Tom (2019-12-01). "Revision of "Bellinurus" carteri (Chelicerata: Xiphosura) from the Late
Devonian of Pennsylvania, USA".
1129:
1116:
542:
1208:
335:
of euchelicerates) and possibly covered by the preceding carapace. The last 3 segments form a narrow postabdomen and lacking lateral nodes.
323:
with blunt genal cornua (posterolateral corners). There is possible evidence of lateral eyes located just below the ophthalmic ridges. The
1193:
997:"Horseshoe crab phylogeny and independent colonizations of fresh water: ecological invasion as a driver for morphological innovation"
896:"A new Ordovician arthropod from the Winneshiek Lagerstätte of Iowa (USA) reveals the ground plan of eurypterids and chasmataspidids"
844:"An unusual euchelicerate linking horseshoe crabs and eurypterids, from the Lower Devonian (Lochkovian) of Yunnan, China"
1198:
1203:
1056:
142:
346:
Compared to other synziphosurines with only scarce or no discovery of any evidence of appendages, the appendages of
1183:
116:
1071:
1155:
439:. However, the lack of doublure (ventral thickening run through the margin of carapace) suggests that
370:
Based on the interpretation of Stürmer & Bergström (1981) and Moore, Briggs & Bartels (2005),
1188:
1103:
907:
894:
Lamsdell, James C.; Briggs, Derek E. G.; Liu, Huaibao P.; Witzke, Brian J.; McKay, Robert M. (2015).
789:
735:
282:
1026:
939:
873:
761:
653:
573:
376:
137:
1160:
1142:
1134:
1018:
977:
931:
923:
865:
817:
809:
753:
701:
645:
565:
293:
124:
1147:
1008:
969:
915:
855:
801:
743:
691:
680:"Revised systematics of Palaeozoic 'horseshoe crabs' and the myth of monophyletic Xiphosura"
637:
557:
475:
289:
1045:
911:
739:
457:
399:. However, the twelve-legged interpretation is not universally accepted - for example,
384:
312:
255:
103:
1177:
996:
895:
765:
696:
679:
577:
417:
197:
61:
1030:
877:
657:
943:
332:
274:
259:
223:
338:
1094:
724:"Pictorial Atlas of Fossil and Extant Horseshoe Crabs, With Focus on Xiphosurida"
498:
483:
466:
412:
324:
263:
184:
36:
973:
919:
805:
396:
392:
355:
81:
46:
1022:
981:
927:
869:
813:
757:
748:
723:
705:
649:
569:
492:
436:
406:
388:
364:
266:
174:
154:
86:
935:
821:
626:(Chelicerata: Xiphosura) from the Lower Devonian Hunsriick Slate, Germany"
1088:
380:
320:
286:
76:
71:
56:
51:
41:
1121:
1013:
641:
561:
432:
328:
316:
297:
91:
66:
860:
543:"Weinbergina, a xiphosuran arthropod from the devonian hunsrĂĽck slate"
270:
164:
1065:
843:
621:
350:
are exceptionally well-preserved in many described fossil materials
620:
Moore, Rachel A.; Briggs, Derek E. G.; Bartels, Christoph (2005).
487:
337:
251:
315:, ranging about 7 cm to 10 cm in full body length. The
1108:
360:
1069:
435:
animal with some degree of swimming ability, similar to modern
416:, while the actual terminations of walking legs (endopods) are
1046:"A summary list of fossil spiders and their relatives"
842:
Selden, Paul A.; Lamsdell, James C.; Qi, Liu (2015).
1078:
788:Dunlop, Jason A.; Lamsdell, James C. (2017-05-01).
722:Bicknell, Russell D. C.; Pates, Stephen (2020).
1044:Dunlop, J. A.; Penney, D.; Jekel, D. (2020).
8:
1066:
790:"Segmentation and tagmosis in Chelicerata"
123:
102:
20:
1012:
859:
747:
695:
684:Zoological Journal of the Linnean Society
541:Stürmer, Wilhelm; Bergström, Jan (1981).
327:is externally 10-segmented, expressed by
490:that included all euchelicerates except
482:was regarded as the basalmost member of
420:(pincer) like those of horseshoe crabs.
363:distal regions and possible evidence of
510:
794:Arthropod Structure & Development
615:
613:
611:
609:
607:
536:
534:
7:
955:
953:
889:
887:
837:
835:
833:
831:
783:
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717:
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593:
591:
589:
587:
532:
530:
528:
526:
524:
522:
520:
518:
516:
514:
474:were once united under the single
354:Underneath the carapace are small
14:
697:10.1111/j.1096-3642.2012.00874.x
342:Fossil with preserved appendages
141:
1:
1209:Fossil taxa described in 1929
796:. Evolution of Segmentation.
319:is covered by a semicircular
630:Paläontologische Zeitschrift
550:Paläontologische Zeitschrift
16:Extinct genus of chelicerate
1057:Natural History Museum Bern
995:Lamsdell, James C. (2016).
678:Lamsdell, James C. (2013).
238:Richter & Richter, 1929
217:Richter & Richter, 1929
1225:
1194:Devonian first appearances
974:10.1016/j.crpv.2019.08.002
728:Frontiers in Earth Science
281:, have been discovered in
920:10.1007/s00114-015-1312-5
806:10.1016/j.asd.2016.05.002
229:
222:
138:Scientific classification
136:
131:
122:
110:
101:
23:
749:10.3389/feart.2020.00098
395:and 4th walking legs of
117:Naturmuseum Senckenberg
962:Comptes Rendus Palevol
343:
311:is a relatively large
1156:Paleobiology Database
900:The Science of Nature
341:
1053:World Spider Catalog
1199:Devonian arthropods
912:2015SciNa.102...63L
740:2020FrEaS...8...98B
622:"A new specimen of
1204:Fossils of Germany
1014:10.1111/pala.12220
642:10.1007/BF02991931
624:Weinbergina opitzi
562:10.1007/BF02988142
344:
273:of the single and
233:Weinbergina opitzi
113:Weinbergina opitzi
1171:
1170:
1143:Open Tree of Life
1072:Taxon identifiers
1059:. pp. 1–296.
861:10.1111/zsc.12124
848:Zoologica Scripta
243:
242:
218:
1216:
1164:
1163:
1151:
1150:
1138:
1137:
1125:
1124:
1112:
1111:
1099:
1098:
1097:
1067:
1061:
1060:
1050:
1041:
1035:
1034:
1016:
992:
986:
985:
957:
948:
947:
891:
882:
881:
863:
839:
826:
825:
785:
770:
769:
751:
719:
710:
709:
699:
675:
662:
661:
617:
582:
581:
547:
538:
431:may have been a
262:group of fossil
216:
209:
146:
145:
127:
106:
96:
33:
29:Temporal range:
21:
1224:
1223:
1219:
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1215:
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1213:
1174:
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1172:
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1038:
994:
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841:
840:
829:
787:
786:
773:
721:
720:
713:
677:
676:
665:
619:
618:
585:
545:
540:
539:
512:
508:
450:
437:horseshoe crabs
426:
306:
239:
236:
215:
207:
140:
132:Reconstruction
97:
95:
94:
89:
84:
79:
74:
69:
64:
59:
54:
49:
44:
39:
31:
30:
27:
17:
12:
11:
5:
1222:
1220:
1212:
1211:
1206:
1201:
1196:
1191:
1186:
1184:Synziphosurina
1176:
1175:
1169:
1168:
1166:
1165:
1152:
1139:
1126:
1113:
1100:
1084:
1082:
1076:
1075:
1070:
1063:
1062:
1036:
1007:(2): 181–194.
987:
968:(8): 967–976.
949:
883:
854:(6): 645–652.
827:
800:(3): 395–418.
771:
711:
663:
636:(3): 399–408.
583:
556:(3): 237–255.
509:
507:
504:
449:
448:Classification
446:
425:
422:
385:horseshoe crab
313:synziphosurine
305:
302:
294:HunsrĂĽck Slate
256:synziphosurine
241:
240:
237:
227:
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55:
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34:
28:
15:
13:
10:
9:
6:
4:
3:
2:
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1210:
1207:
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1202:
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1001:Palaeontology
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584:
579:
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552:(in German).
551:
544:
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531:
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253:
249:
248:
235:
234:
228:
225:
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214:
213:
206:
203:
202:
199:
198:Euchelicerata
196:
193:
190:
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179:
176:
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48:
43:
38:
26:
22:
19:
1079:
1052:
1039:
1004:
1000:
990:
965:
961:
906:(9–10): 63.
903:
899:
851:
847:
797:
793:
731:
727:
687:
683:
633:
629:
623:
553:
549:
497:
491:
479:
472:Willwerathia
471:
465:
461:
453:
451:
440:
428:
427:
424:Paleoecology
411:
405:
400:
371:
369:
351:
347:
345:
333:synapomorphy
308:
307:
278:
275:type species
260:paraphyletic
246:
245:
244:
232:
231:
224:Type species
211:
210:
191:
112:
24:
18:
1189:Prosomapoda
1080:Weinbergina
690:(1): 1–27.
499:Dibasterium
484:Prosomapoda
480:Weinbergina
467:Legrandella
462:Weinbergina
454:Weinbergina
441:Weinbergina
429:Weinbergina
413:Dibasterium
401:Weinbergina
393:dekatriatan
372:Weinbergina
348:Weinbergina
325:opisthosoma
309:Weinbergina
264:chelicerate
247:Weinbergina
212:Weinbergina
185:Chelicerata
181:Subphylum:
25:Weinbergina
1178:Categories
506:References
444:sediment.
397:sea spider
377:homologous
365:book gills
356:chelicerae
304:Morphology
267:arthropods
175:Arthropoda
111:Fossil of
1095:Q18609111
1023:1475-4983
982:1631-0683
928:0028-1042
870:0300-3256
814:1467-8039
766:220405124
758:2296-6463
706:0024-4082
650:0031-0220
578:128408596
570:0031-0220
493:Offacolus
407:Offacolus
389:metastoma
379:with the
279:W. opitzi
161:Kingdom:
155:Eukaryota
1089:Wikidata
1031:85553811
936:26391849
878:55264483
822:27240897
658:84994966
381:chilaria
329:tergites
321:carapace
287:Devonian
283:deposits
171:Phylum:
165:Animalia
151:Domain:
32:Devonian
1148:3581683
1135:1066567
1122:4649977
1109:4305528
944:8153035
908:Bibcode
736:Bibcode
460:genus,
433:benthic
418:chelate
317:prosoma
298:Germany
292:in the
285:of the
271:Fossils
204:Genus:
1029:
1021:
980:
942:
934:
926:
876:
868:
820:
812:
764:
756:
734:: 98.
704:
656:
648:
576:
568:
476:family
361:setose
290:period
1161:18943
1130:IRMNG
1049:(PDF)
1027:S2CID
940:S2CID
874:S2CID
762:S2CID
654:S2CID
574:S2CID
546:(PDF)
488:clade
452:With
252:genus
250:is a
192:Clade
1117:GBIF
1019:ISSN
978:ISSN
932:PMID
924:ISSN
866:ISSN
818:PMID
810:ISSN
754:ISSN
702:ISSN
646:ISSN
566:ISSN
496:and
486:, a
470:and
458:type
410:and
258:, a
37:Preęž’
1104:EoL
1009:doi
970:doi
916:doi
904:102
856:doi
802:doi
744:doi
692:doi
688:167
638:doi
558:doi
456:as
391:of
383:of
254:of
1180::
1158::
1145::
1132::
1119::
1106::
1091::
1055:.
1051:.
1025:.
1017:.
1005:59
1003:.
999:.
976:.
966:18
964:.
952:^
938:.
930:.
922:.
914:.
902:.
898:.
886:^
872:.
864:.
852:44
850:.
846:.
830:^
816:.
808:.
798:46
792:.
774:^
760:.
752:.
742:.
730:.
726:.
714:^
700:.
686:.
682:.
666:^
652:.
644:.
634:79
632:.
628:.
586:^
572:.
564:.
554:55
548:.
513:^
502:.
464:,
387:,
367:.
300:.
296:,
277:,
269:.
194::
115:,
87:Pg
1033:.
1011::
984:.
972::
946:.
918::
910::
880:.
858::
824:.
804::
768:.
746::
738::
732:8
708:.
694::
660:.
640::
580:.
560::
352:.
230:â€
208:â€
92:N
82:K
77:J
72:T
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42:ęž’
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