115:
338:
136:
480:, only an appendage belonging to the sixth pair with five distal podomeres (podomeres that were not underneath the prosoma) is known. The seventh and eighth podomeres (and perhaps more of them) were somewhat prolonged outwards and flattened. They featured spine-like immovable spurs on their anterior margins. On the posterior margin of the seventh podomere was the movable spine-like podomere 7a, characteristic of the
550:
507:
half of the segment) being less wide than the subsequent ones. The postabdomen was narrow, had a constant width and did not have epimera (lateral "extensions" of the segment), like the preabdomen. The segments of the whole body were hardly distinguishable from each other. The integument of the body
718:, determining that it could no longer be classified as part of Drepanopteridae, thus erecting the new family Alkenopteridae for it. This family was not assigned to any superfamily due to the poor knowledge of the second to fourth appendages of its only genus,
540:
was long, measuring 0.35 cm (0.14 in) in a specimen with 2.03 cm (0.80 in) in total, with a ratio significantly small of 5.8. It had an expanded anterior portion as well. The telson of both species had, however, the same styliform shape.
682:
from Alken, 624-D (a well-preserved prosoma with remains of appendages) and 697-D (a fragmentary specimen with the prosoma, appendages, preabdomen, the last two postabdominal segments and telson). They also redescribed the holotype of
425:
were placed in the center of the carapace. They were reniform (bean-shaped), with a strongly arcuate visual surface (a "half moon" in the eye). Between the eyes was located a
730:-type" sixth appendage, this one having podomeres almost equal in length (except the distal spine) and moderately flattened. Both pairs of appendages lacked spines. The
1087:
762:. This resulted in the detection of a movable podomere 7a instead of a simple projection as previously thought. Therefore, Poschmann assigned it to the family
674:
In 2004, paleontologists Markus
Poschmann and Odd Erik Tetlie described a series of new fossils found in the Nellenköpfchen Formation, in the center of the
414:
part covering the prosoma) was rounded in the front. Its surface was somewhat inflated, being distinguished several narrow grooves and ridges, most of them
1074:
699:
as Alken). PWL 2002/5011 LS is almost complete and well-preserved but somewhat distorted; it is the only known find of this species. It was named
536:"keel" (ridge), with an expanded anterior base articulated to the pretelson (segment that preceded the telson). In the other hand, the telson of
1151:
579:) is a smaller, little preserved and strongly telescoped (with segments overlapping each other, a defect product of the fossilization of the
866:
Poschmann, Markus; Tetlie, Odd Erik (2004). "On the Emsian (Early
Devonian) arthropods of the Rhenish Slate Mountains: 4. The eurypterids
826:"Arthropods from the Lower Devonian (Lower Emsian) of Alken an der Mosel, Germany. Part 4: Eurypterida, Drepanopteridae, and other groups"
1004:
532:
between the total body length and telson of this specimen is around 13.6. It was slightly subtriangular (almost triangular) and had a
499:
1 to 7) and a postabdomen (segments 8 to 12). The preabdomen had lateral convex margins and was quite short and broad, with the first
924:
792:
484:. All the podomeres had similar proportions, except the distal spine which was slightly curved and probably had a pointed tip.
472:
groove. The third to fifth appendages are also known, but they are not exceptionally preserved. Nevertheless, in all of them a
1161:
711:, the former having a longer and broader telson and more strongly expanded distal podomeres in appendage VI than the latter.
1146:
642:(short) and the Ancient Greek word τέλσον (literally "terminal", but here referring to the telson). Størmer also compared
441:
also had between the eyes, behind the tubercle, certain grooves resembling the reversed V-shaped structure found in some
533:
504:
469:
135:
1156:
1141:
584:
387:, represents in fact the smallest species of eurypterid known as far, only measuring 2.03 cm (0.80 in).
787:
114:
495:) suffered a strong to moderate first order differentiation, that is, it was divided into a preabdomen (body
628:
620:
608:
337:
703:, the specific name coming from Burglahr due to the proximity of its type locality with this municipality.
1042:
496:
1113:
528:
was short, measuring only 0.55 cm (0.22 in) in a 7.5 cm (3.0 in) long specimen. The
596:
509:
403:
1023:
980:
941:
891:
130:
1118:
1100:
1092:
763:
696:
419:
310:
216:
203:
1105:
961:"Phylogeny and palaeoecology of the Adelophthalmoidea (Arthropoda; Chelicerata; Eurypterida)"
1013:
972:
933:
883:
755:
751:
714:
Poschmann and Tetlie claimed to find no evidence of a podomere 7a in the sixth appendage of
662:
746:
for not possessing the podomere 7a. However, in 2014, Poschmann reexamined the holotype of
464:(leg segments) were more or less rectangular and constant in width. In the end there was a
465:
434:
364:
1000:"The systematics and phylogeny of the Stylonurina (Arthropoda: Chelicerata: Eurypterida)"
734:-type leg was introduced as a new standard type of non-spiniferous eurypterid appendage.
564:
236:
394:(head) was large, with a subquadrate (almost square) to semielliptic (nearly elliptic),
675:
667:
592:
561:
351:
1135:
960:
945:
915:
895:
825:
759:
648:
616:
449:
346:
72:
1027:
984:
766:, with whom it shared several characteristics. It is assumed that in the fossils of
654:
604:
588:
422:
245:
549:
659:
488:
481:
442:
411:
177:
47:
1065:
1018:
999:
976:
937:
372:
306:
190:
92:
57:
739:
395:
167:
147:
97:
41:
920:(Chelicerata: Eurypterida: Eurypterina) from the Lower Devonian of Germany"
1059:
743:
692:
580:
576:
568:
461:
426:
407:
399:
322:
87:
82:
67:
62:
52:
1079:
887:
600:
500:
492:
456:
are not known in much detail. A pair of poorly preserved appendages of
415:
391:
376:
326:
102:
77:
30:
468:
about as long as the podomeres which was slightly curved, with a long
572:
521:
473:
430:
157:
34:
1036:
691:
was found in another locality in the
Nellenköpfchen Formation, near
635:
548:
529:
336:
770:, this podomere was not preserved, but if this is not the case,
627:, "wing"), commonly used in eurypterids. On the other hand, the
575:
with almost all the appendages missing, while SMF VIII 241 (the
1040:
567:
described two specimens of a new eurypterid. SMF VIII 150 (the
998:
Lamsdell, James C.; Braddy, Simon J.; Tetlie, O. Erik (2010).
383:, being 7.5 centimetres (3.0 inches) long. The other species,
460:
representing the sixth (and last) pair of them is known. The
402:
surrounded by a broad and flat marginal rim that reached its
726:-type B (with no podomere 7a) fifth appendage and an "
524:(the posteriormost division of the body). The one of
742:) would be subsequently included in the Stylonurina
1049:
916:"Note on the morphology and systematic position of
615:, with the generic name composed by Alken and the
512:and was very smooth. The main difference between
959:Erik Tetlie, O; Poschmann, Markus (2008-06-01).
678:, Germany. Among them were two new specimens of
571:) is a relatively complete and well preserved
8:
1037:
722:. Alkenopteridae was distinguished by the
687:. Further, a specimen of a new species of
113:
20:
1017:
774:should be reassigned to Stylonurina and
803:
583:) specimen. Both were collected in the
349:(limbs) are based on a close relative,
607:). Currently, they are located in the
665:Drepanopteridae doubtfully alongside
7:
909:
907:
905:
874:n. gen. (Arthropoda: Chelicerata)".
861:
859:
857:
855:
853:
851:
849:
847:
845:
843:
819:
817:
815:
813:
811:
809:
807:
1005:Journal of Systematic Palaeontology
965:Journal of Systematic Palaeontology
553:Size comparison of both species of
476:spine can be identified. Regarding
750:by carefully removing some of the
355:, while the fifth one is based on
313:. The genus contains two species,
14:
738:(as well as Drepanopteridae, now
309:classified as part of the family
778:to a new onychopterellid genus.
611:. This new eurypterid was named
134:
793:Timeline of eurypterid research
345:. The second to fourth pair of
122:SMF VIII 150, the holotype of
1:
1152:Fossil taxa described in 1974
925:Paläontologische Zeitschrift
291:Poschmann & Tetlie, 2004
16:Extinct genus of arthropods
1178:
918:Alkenopterus burglahrensis
914:Poschmann, Markus (2014).
305:is a genus of prehistoric
1019:10.1080/14772011003603564
977:10.1017/S1477201907002416
938:10.1007/s12542-013-0189-x
788:List of eurypterid genera
433:(simple eye-like sensory
270:
265:
255:Alkenopterus brevitelson
251:
244:
131:Scientific classification
129:
121:
112:
23:
754:of the fossil and using
613:Alkenopterus brevitelson
585:Nellenköpfchen Formation
124:Alkenopterus brevitelson
876:Senckenbergiana Lethaea
830:Senckenbergiana Lethaea
609:Naturmuseum Senckenberg
824:Størmer, Leif (1974).
658:, placing them in the
557:
520:was the length of the
398:-like outline. It was
360:
352:Onychopterella augusti
1162:Eurypterids of Europe
1114:Paleobiology Database
552:
429:or node carrying the
418:-like. The prominent
340:
1147:Devonian eurypterids
707:was very similar to
597:Rhineland-Palatinate
545:History of research
1157:Fossils of Germany
1142:Onychopterelloidea
888:10.1007/BF03043470
558:
361:
204:Onychopterelloidea
1129:
1128:
1101:Open Tree of Life
1043:Taxon identifiers
764:Onychopterellidae
634:derives from the
311:Onychopterellidae
298:
297:
292:
281:
240:
217:Onychopterellidae
1169:
1122:
1121:
1109:
1108:
1096:
1095:
1083:
1082:
1070:
1069:
1068:
1038:
1032:
1031:
1021:
995:
989:
988:
956:
950:
949:
911:
900:
899:
882:(1–2): 173–193.
863:
838:
837:
821:
776:A. burglahrensis
756:light microscopy
748:A. burglahrensis
705:A. burglahrensis
701:A. burglahrensis
538:A. burglahrensis
518:A. burglahrensis
478:A. burglahrensis
385:A. burglahrensis
365:onychopterellids
343:A. burglahrensis
321:, both from the
319:A. burglahrensis
290:
287:A. burglahrensis
279:
235:
228:
215:
202:
189:
139:
138:
117:
107:
44:
29:Temporal range:
21:
1177:
1176:
1172:
1171:
1170:
1168:
1167:
1166:
1132:
1131:
1130:
1125:
1117:
1112:
1104:
1099:
1091:
1086:
1078:
1073:
1064:
1063:
1058:
1045:
1035:
997:
996:
992:
958:
957:
953:
913:
912:
903:
865:
864:
841:
823:
822:
805:
801:
784:
547:
363:Like the other
341:Restoration of
335:
261:
258:
234:
226:
213:
200:
187:
133:
108:
106:
105:
100:
95:
90:
85:
80:
75:
70:
65:
60:
55:
50:
40:409–402.5
39:
38:
27:
17:
12:
11:
5:
1175:
1173:
1165:
1164:
1159:
1154:
1149:
1144:
1134:
1133:
1127:
1126:
1124:
1123:
1110:
1097:
1084:
1071:
1055:
1053:
1047:
1046:
1041:
1034:
1033:
990:
971:(2): 237–249.
951:
932:(2): 223–226.
901:
839:
802:
800:
797:
796:
795:
790:
783:
780:
772:A. brevitelson
768:A. brevitelson
758:with a higher
709:A. brevitelson
685:A. brevitelson
680:A. brevitelson
676:Rhenish Massif
668:Onychopterella
562:paleontologist
546:
543:
526:A. brevitelson
514:A. brevitelson
458:A. brevitelson
439:A. brevitelson
381:A. brevitelson
375:. The largest
357:A. brevitelson
334:
331:
315:A. brevitelson
296:
295:
294:
293:
282:
276:A. brevitelson
268:
267:
263:
262:
259:
249:
248:
242:
241:
224:
220:
219:
211:
207:
206:
198:
194:
193:
185:
181:
180:
175:
171:
170:
165:
161:
160:
155:
151:
150:
145:
141:
140:
127:
126:
119:
118:
110:
109:
101:
96:
91:
86:
81:
76:
71:
66:
61:
56:
51:
46:
45:
28:
15:
13:
10:
9:
6:
4:
3:
2:
1174:
1163:
1160:
1158:
1155:
1153:
1150:
1148:
1145:
1143:
1140:
1139:
1137:
1120:
1115:
1111:
1107:
1102:
1098:
1094:
1089:
1085:
1081:
1076:
1072:
1067:
1061:
1057:
1056:
1054:
1052:
1048:
1044:
1039:
1029:
1025:
1020:
1015:
1011:
1007:
1006:
1001:
994:
991:
986:
982:
978:
974:
970:
966:
962:
955:
952:
947:
943:
939:
935:
931:
927:
926:
921:
919:
910:
908:
906:
902:
897:
893:
889:
885:
881:
877:
873:
869:
862:
860:
858:
856:
854:
852:
850:
848:
846:
844:
840:
835:
831:
827:
820:
818:
816:
814:
812:
810:
808:
804:
798:
794:
791:
789:
786:
785:
781:
779:
777:
773:
769:
765:
761:
760:magnification
757:
753:
749:
745:
741:
737:
733:
729:
725:
724:Drepanopterus
721:
717:
712:
710:
706:
702:
698:
695:(in the same
694:
690:
686:
681:
677:
672:
670:
669:
664:
661:
657:
656:
651:
650:
649:Drepanopterus
645:
641:
637:
633:
630:
629:specific name
626:
622:
618:
617:Ancient Greek
614:
610:
606:
602:
598:
594:
590:
586:
582:
578:
574:
570:
566:
563:
556:
551:
544:
542:
539:
535:
531:
527:
523:
519:
515:
511:
510:ornamentation
506:
502:
498:
494:
490:
485:
483:
479:
475:
471:
467:
463:
459:
455:
451:
446:
444:
440:
436:
432:
428:
424:
421:
417:
413:
409:
406:corners. The
405:
401:
397:
393:
388:
386:
382:
378:
374:
370:
366:
358:
354:
353:
348:
344:
339:
332:
330:
328:
324:
320:
316:
312:
308:
304:
303:
289:
288:
283:
280:Størmer, 1974
278:
277:
272:
271:
269:
264:
260:Størmer, 1974
257:
256:
250:
247:
243:
238:
233:
232:
225:
222:
221:
218:
212:
209:
208:
205:
199:
197:Superfamily:
196:
195:
192:
186:
183:
182:
179:
176:
173:
172:
169:
166:
163:
162:
159:
156:
153:
152:
149:
146:
143:
142:
137:
132:
128:
125:
120:
116:
111:
104:
99:
94:
89:
84:
79:
74:
69:
64:
59:
54:
49:
43:
36:
32:
26:
22:
19:
1051:Alkenopterus
1050:
1012:(1): 49–61.
1009:
1003:
993:
968:
964:
954:
929:
923:
917:
879:
875:
872:Vinetopterus
871:
868:Alkenopterus
867:
833:
829:
775:
771:
767:
747:
736:Alkenopterus
735:
732:Alkenopterus
731:
728:Alkenopterus
727:
723:
720:Alkenopterus
719:
716:Alkenopterus
715:
713:
708:
704:
700:
689:Alkenopterus
688:
684:
679:
673:
666:
655:Moselopterus
653:
647:
644:Alkenopterus
643:
639:
631:
624:
612:
605:West Germany
589:municipality
565:Leif Størmer
559:
555:Alkenopterus
554:
537:
525:
517:
513:
486:
482:eurypterines
477:
470:longitudinal
457:
454:Alkenopterus
453:
447:
443:stylonurines
438:
389:
384:
380:
371:was a small
369:Alkenopterus
368:
362:
356:
350:
342:
318:
314:
302:Alkenopterus
301:
300:
299:
286:
285:
275:
274:
254:
253:
246:Type species
231:Alkenopterus
230:
229:
123:
35:Early Emsian
31:Late Pragian
25:Alkenopterus
24:
18:
660:stylonuroid
632:brevitelson
489:opisthosoma
452:(limbs) of
412:exoskeleton
333:Description
191:Eurypterida
178:Chelicerata
174:Subphylum:
1136:Categories
836:: 359–451.
799:References
450:appendages
400:anteriorly
373:eurypterid
347:appendages
307:eurypterid
168:Arthropoda
946:132432538
896:127313845
740:monotypic
587:near the
560:In 1974,
462:podomeres
404:posterior
396:horseshoe
154:Kingdom:
148:Eukaryota
1066:Q4727682
1060:Wikidata
1028:85398946
985:59488956
782:See also
744:suborder
693:Burglahr
581:organism
577:paratype
569:holotype
497:segments
427:tubercle
408:carapace
323:Devonian
266:Species
210:Family:
164:Phylum:
158:Animalia
144:Domain:
1106:3581728
1093:1266170
1080:4650078
619:suffix
601:Germany
508:lacked
501:tergite
493:abdomen
420:lateral
416:wrinkle
392:prosoma
377:species
327:Germany
237:Størmer
223:Genus:
184:Order:
1026:
983:
944:
894:
752:matrix
663:family
640:brevis
625:pteron
621:πτερόν
603:(then
573:fossil
534:median
522:telson
505:dorsal
474:distal
435:organs
431:ocelli
239:, 1974
1119:18950
1088:IRMNG
1024:S2CID
981:S2CID
942:S2CID
892:S2CID
697:state
646:with
638:word
636:Latin
593:Alken
530:ratio
466:spine
410:(the
1075:GBIF
870:and
652:and
516:and
487:The
448:The
423:eyes
390:The
379:was
317:and
48:PreꞒ
1014:doi
973:doi
934:doi
884:doi
595:in
591:of
437:).
325:of
1138::
1116::
1103::
1090::
1077::
1062::
1022:.
1008:.
1002:.
979:.
967:.
963:.
940:.
930:88
928:.
922:.
904:^
890:.
880:84
878:.
842:^
834:54
832:.
828:.
806:^
671:.
599:,
445:.
367:,
329:.
98:Pg
42:Ma
37:,
1030:.
1016::
1010:8
987:.
975::
969:6
948:.
936::
898:.
886::
623:(
503:(
491:(
359:.
284:†
273:†
252:†
227:†
214:†
201:†
188:†
103:N
93:K
88:J
83:T
78:P
73:C
68:D
63:S
58:O
53:Ꞓ
33:-
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