Abstract

Cladistic parsimony analysis of the subfamily Deiphoninae Raymond, 1913 was conducted to produce a hypothesis of relationship for the group. The genera DeiphonBarrande, 1850 and OnycopygeWoodward, 1880 are found to be monophyletic, while the genus SphaerocorypheAngelin, 1854, as it was previously defined, is paraphyletic. A modified Brooks Parsimony Analysis using the phylogenetic hypothesis reveals patterns of biogeography, in particular, vicariance and geodispersal, during the Ordovician-Silurian. The analysis yields three major conclusions about deiphonine biogeography: Eastern Laurentia and Baltica were close enough during the late Ordovician to exchange taxa via sea level rise and fall; chance dispersal occurred between Northwestern Laurentia and Australia; and deiphonine trilobites likely originated in Baltica or Eastern Laurentia.

You do not currently have access to this article.