Compare the above pictorial approach to the purely narrative description
Cephalon: proparian sutures (a few opisthoparian), glabella usually expanding forwards or barrel-shaped, up to 4 pairs of furrows; holochroal eyes, often small; gena often with fine pitting; with rostral plate; hypostome conterminant, with anterior wing bearing prominent process.
Thorax: variable numbers of distinctive segments within Phacopida range of 8-19, often spine-tipped.
Pygidium: often highly modified with 2-16 distinct pairs of ribs, and lobed or spinose margin.
Other: often with tuberculate exoskeleton.
Superfamilies/Families: Cheiruroidea/Cheiruridae, Encrinuridae, Hammatocnemidae, Pilekiidae, Pliomeridae, Staurocephalidae
Representative Genera: Ceraurus, Cheirurus, Coronocephalina, Crotalocephalina, Cybeloides, Cyrtometopus, Encrinuroides, Encrinurus, Heliomera, Ktenoura, Lyrapyge, Pilekia, Placoparia, Pliomera, Pseudocybele, Sphaerocoryphe, Sphaerexochus, Staurocephalus
Here are some members of the Cheirurina
PHACOPIDA includes three Suborders
Return to Phacopida Fact Sheet
Walking Trilobite animation ©2000 by S. M. Gon III
All line drawings this page ©1999 - 2008 by S. M. Gon III