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326:) is roughly pentangular, and it substantially overhangs the frontal cephalic border. The cheeks are roughly triangular, with the eyes (or palpebral lobes) occupying the frontal quarter of its length. The eye has between 1 and 11 or more individual lenses. The pygidium is more than 3 times wider than long and is almost rectangular because the posterior thorax segments angle backwards when approaching the side of the exoskeleton.
301:
is an example of rapid evolution. Subsequent populations exhibit a declining average and an increasing variation in the number of lenses per eye from about 10 to between 7 and 1. This rapid trend does not occur in other characters of the exoskeleton. This suggests the absence rather than the presence
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348:"Variation in the eye of Acuticryphops (Phacopina, Trilobita) and its evolutionary significance: a biometric and morphometric approach"
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Feist, R. (2002). "Trilobites from the latest
Frasnian Kellwasser Crisis in North Africa (Mrirt, central Moroccan Meseta)".
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405:"Trilobites between Lower and Upper Kellwasser events, Mrirt area, Morocco (Devonian of Morocco)"
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of selective pressure on the number of lenses per eye. This is presumably associated with the
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Crônier, Catherine; Feist, Raimund; Auffray, Jean-Christophe (2004).
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10.1666/0094-8373(2004)030<0471:viteoa>2.0.co;2
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284:was probably ancestral to the species of the genus
250:is a genus of trilobite that lived during the late
265:(Harz Mountains and Rhenish Slate Mountains) and
322:). The central raised area of the cephalon (or
273:margin (Coumiac, France and central Morocco).
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318:has a rounded triangular headshield (or
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269:(Thuringia: Schleiz) and the North
570:. You can help Knowledge (XXG) by
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261:. It is known from mid-European
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642:Devonian trilobites of Africa
622:Devonian trilobites of Europe
394:Acta Palaeontologica Polonica
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125:Scientific classification
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316:Acuticryphops acuticeps
299:Acuticryphops acuticeps
203:Cronier and Feist, 2000
566:-related article is a
529:Paleobiology Database
637:Fossils of Morocco
632:Fossils of Germany
304:eustatic deepening
235:Cryphops acuticeps
627:Fossils of France
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516:Open Tree of Life
432:Taxon identifiers
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231:Phacops acuticeps
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314:In dorsal view,
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26:Temporal range:
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358:(3): 471–481.
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440:Acuticryphops
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400:(2): 203–210.
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22:Acuticryphops
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572:expanding it
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412:. Retrieved
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375:. Retrieved
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352:Paleobiology
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219:A. acuticeps
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414:17 December
409:Fossilworks
377:23 December
310:Description
617:Phacopidae
611:Categories
330:References
256:Kellwasser
184:Phacopidae
148:Arthropoda
564:Phacopida
455:Q15409318
402:cited in
294:Evolution
172:Phacopida
160:Trilobita
131:Kingdom:
449:Wikidata
372:86285217
324:glabella
320:cephalon
277:Taxonomy
271:Gondwana
267:Armorica
263:Avalonia
259:horizons
252:Frasnian
179:Family:
143:Phylum:
136:Animalia
30:Frasnian
521:4705824
508:1189213
495:4632992
482:4322176
210:species
191:Genus:
167:Order:
155:Class:
97:↓
370:
562:This
534:56894
503:IRMNG
368:S2CID
568:stub
490:GBIF
416:2021
379:2013
224:type
36:PreꞒ
477:EoL
469:NVJ
464:CoL
360:doi
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338:^
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362::
228:=
91:N
81:K
76:J
71:T
66:P
61:C
56:D
51:S
46:O
41:Ꞓ
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