22048 - Nicely Preserved 3.59 Inch Crotalocephalina (Crotalocephalus) gibbus Lower Devonian Trilobite Dyrosaurus phosphaticus • Silurian of Canada (

• Silurian of Canada ( Northwest Territories

They are characterised by a shovel-like cephalon (head)

Impressive specimen of the genus Cyphaspis

The exact taxonomic classification is complex given that there are very few published studies that refer to the claw rests of the Pterosaurs in the North African Upper Cretaceous

22048 - Nicely Preserved 3.59 Inch Crotalocephalina (Crotalocephalus) gibbus Lower Devonian Trilobite Dyrosaurus phosphaticus • Silurian of Canada (Nice and well prepared specimen. Crotalocephalina sp, Pibyl and Vanek 1964 (trilobite) Trilobita Phacopida Cheiruridae Parent taxon: Cheiruridae according to P. A. Jell and J. M. Adrain 2002 See also Sepkoski 2002 Sister taxa: Acanthoparyphinae, Anasobella, Ancyginaspis, Arcticeraurinella, Areia, Areiaspis, Borealaspis, Bornholmaspis, Ceraurinium, Ceraurinus, Cerauroides, Cerauromeros, Cerauropeltis, Ceraurus, Chacomurus, Cheirurinae, Cheirurus,