108:
367:
indicates a calm environment with little influx of terrestrial silt. There is an alternation of dark and light layers, which may indicate a seasonal change, such as freezing over in winter. The bottom of the lake was probably
290:. Twelve specimens are known, with a total body length of 3–5 cm (1.2–2.0 in). On some specimens, details of the internal anatomy can be seen due to the exceptional preservation.
356:
rocks. They are formed from lake deposits, based on the presence of five families of freshwater fish and other terrestrial taxa, and the fossil-bearing sediments have been dated to the
745:
510:
therefore relied on the form of the telson, which has a diaeresis (division into two halves) in
Astacoidea, but none in Parastacoidea; this distinction was noted by
498:
The chief distinction between the
Northern Hemisphere superfamily Astacoidea and the Southern Hemisphere superfamily Parastacoidea is usually the form of the
668:
750:
542:
Fossils of freshwater crayfish are extremely rare. Only 13 species are known in total, and only two from North
America, the Astacidae species
558:, by contrast, belongs to the Southern Hemisphere family Parastacidae, and is that family's only Northern Hemisphere representative.
755:
707:
602:
449:
598:"New Eocene crayfish from the McAbee Beds in British Columbia: First record of Parastacoidea in the Northern Hemisphere"
492:
320:
107:
740:
266:
544:
481:
550:
429:
636:
302:
735:
694:
220:
712:
519:
511:
534:, suggesting that its apparent absence from the telson is not merely an artefact of preservation.
306:
102:
699:
384:
have been recovered, with total body lengths of between 3–5 centimetres (1.2–2.0 in). The
681:
488:
393:
389:
686:
611:
515:
310:
270:
282:
353:
729:
433:
405:
369:
61:
471:
421:
357:
278:
179:
149:
425:
169:
36:
659:
453:
by Rodney
Feldmann, Carrie Schweitzer and John Leahy in 2011. The genus name,
81:
46:
335:
322:
499:
404:
are larger than the others, and are armed with a nearly symmetrical pair of
401:
349:
139:
119:
86:
464:
653:
530:, which is seen in both superfamilies, is preserved in some specimens of
400:
have not been preserved on any of the known specimens. The first pair of
385:
360:
274:
259:
159:
76:
71:
56:
51:
41:
480:, which is frequently used as a suffix for genus names of crayfish. The
673:
554:, both of which belong to families still represented in North America.
476:
420:
show exceptional preservation. In some specimens, dark areas formed of
252:
91:
66:
616:
597:
412:(abdomen) is generally smooth, and ends in a broad, slightly tapering
527:
413:
364:
314:
263:
256:
129:
630:
458:
409:
348:. The McAbee beds comprise a 30-metre (100 ft) thickness of
634:
397:
502:, but these have not been preserved in any known specimen of
273:, and was described in 2011. It is the first member of the
363:. The deposition of a silica-rich sediment deriving from
372:, which may have aided the preservation of fossils.
643:
522:. While no diaeresis is visible on the telson of
596:Feldmann, R.; Schweitzer, C.; Leahy, J. (2011).
447:was described as a new genus and species in the
8:
281:to be found in the Northern Hemisphere, and
462:
631:
591:
20:
615:
589:
587:
585:
583:
581:
579:
577:
575:
573:
571:
352:sediments within a sequence dominated by
746:Freshwater crustaceans of North America
567:
432:of extant crayfishes. The trace of the
424:can be seen, which appear to represent
380:Twelve "nearly complete" specimens of
239:Feldmann, Schweitzer & Leahy, 2011
199:Feldmann, Schweitzer & Leahy, 2011
396:are as long as the carapace, but the
7:
416:with no diaeresis. The specimens of
436:is also visible in some specimens.
14:
487:commemorates the crayfish expert
428:in a pattern congruent with the
283:is the only species in the genus
267:Okanagan Highlands lake deposits
106:
1:
751:Fossil taxa described in 2011
603:Journal of Crustacean Biology
474:", and the name of the genus
450:Journal of Crustacean Biology
493:George Washington University
388:is thin and the form of the
548:and the Cambaridae species
772:
226:
219:
103:Scientific classification
101:
23:
16:Extinct genus of crayfish
756:Monotypic decapod genera
336:50.786350°N 121.142800°W
262:. It was found in early
645:Aenigmastacus crandalli
545:Pacifastacus chenoderma
445:Aenigmastacus crandalli
248:Aenigmastacus crandalli
233:Aenigmastacus crandalli
25:Aenigmastacus crandalli
463:
341:50.786350; -121.142800
301:was discovered in the
695:Paleobiology Database
551:Procambarus primaevus
526:, a diaeresis on the
430:endophragmal skeleton
303:Tranquille Formation
277:-distributed family
520:Horton H. Hobbs, Jr
512:Thomas Henry Huxley
457:, derives from the
332: /
260:freshwater crayfish
741:Eocene crustaceans
392:is not known. The
307:McAbee Fossil Beds
723:
722:
682:Open Tree of Life
637:Taxon identifiers
617:10.1651/10-3399.1
489:Keith A. Crandall
244:
243:
212:A. crandalli
200:
763:
716:
715:
703:
702:
690:
689:
677:
676:
664:
663:
662:
632:
622:
621:
619:
593:
516:Martin Glaessner
482:specific epithet
468:
434:alimentary tract
347:
346:
344:
343:
342:
337:
333:
330:
329:
328:
325:
311:British Columbia
271:British Columbia
235:
231:
198:
191:
111:
110:
96:
33:
29:Temporal range:
21:
771:
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84:
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12:
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5:
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718:
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691:
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641:
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635:
624:
623:
610:(2): 320–331.
566:
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560:
539:
536:
441:
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377:
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354:volcaniclastic
295:
292:
242:
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28:
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6:
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3:
2:
768:
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588:
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582:
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578:
576:
574:
572:
568:
561:
559:
557:
556:Aenigmastacus
553:
552:
547:
546:
537:
535:
533:
532:Aenigmastacus
529:
525:
524:Aenigmastacus
521:
517:
513:
509:
505:
504:Aenigmastacus
501:
496:
494:
490:
486:
483:
479:
478:
473:
469:
467:
466:
460:
456:
455:Aenigmastacus
452:
451:
446:
439:
437:
435:
431:
427:
423:
419:
418:Aenigmastacus
415:
411:
408:(claws). The
407:
403:
399:
395:
391:
387:
383:
382:Aenigmastacus
375:
373:
371:
366:
362:
359:
358:Early Eocenes
355:
351:
345:
316:
312:
308:
304:
300:
299:Aenigmastacus
293:
291:
289:
288:
287:Aenigmastacus
284:
280:
276:
272:
268:
265:
261:
258:
254:
250:
249:
236:
234:
225:
222:
221:Binomial name
218:
214:
213:
207:
204:
203:
196:
195:
194:Aenigmastacus
188:
185:
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93:
88:
83:
78:
73:
68:
63:
58:
53:
48:
43:
38:
26:
22:
19:
736:Parastacidae
644:
627:
607:
601:
555:
549:
543:
541:
538:Biogeography
531:
523:
507:
503:
497:
484:
475:
472:inexplicable
461:
454:
448:
444:
443:
422:fluorapatite
417:
381:
379:
298:
297:
294:Distribution
286:
285:
279:Parastacidae
247:
246:
245:
232:
227:
211:
210:
193:
192:
180:Parastacidae
150:Malacostraca
24:
18:
506:. Feldmann
470:, meaning "
426:soft tissue
376:Description
339: /
327:121°8.568′W
324:50°47.181′N
170:Pleocyemata
730:Categories
562:References
402:pereiopods
166:Suborder:
140:Arthropoda
500:genitalia
485:crandalli
350:siliceous
205:Species:
126:Kingdom:
120:Eukaryota
660:Q4687834
654:Wikidata
440:Taxonomy
394:antennae
386:carapace
361:Ypresian
275:Gondwana
176:Family:
160:Decapoda
136:Phylum:
130:Animalia
116:Domain:
32:Ypresian
687:6185018
674:8037818
528:uropods
477:Astacus
465:aenigma
390:rostrum
365:diatoms
253:species
230:†
209:†
186:Genus:
156:Order:
146:Class:
713:853698
700:217955
508:et al.
414:telson
406:chelae
370:anoxic
315:Canada
264:Eocene
257:fossil
708:WoRMS
459:Latin
410:pleon
317:, at
251:is a
669:GBIF
518:and
398:eyes
37:PreꞒ
612:doi
491:of
309:of
305:'s
269:in
255:of
732::
710::
697::
684::
671::
656::
608:31
606:.
600:.
570:^
514:,
495:.
313:,
87:Pg
620:.
614::
190:†
92:N
82:K
77:J
72:T
67:P
62:C
57:D
52:S
47:O
42:Ꞓ
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