Article: Boreopricea from the Lower Triassic of Russia, and the relationships of the prolacertiform reptiles

Boreopricea funerea from the Lower Triassic of northern Russia is a prolacertiform diapsid, superficially similar to Prolacerta from the Lower Triassic of South Africa. The skull is damaged, but relatively complete. The lower temporal bar is absent. Some parts of the skeleton of Boreopricea, in particular some of the vertebrae and the foot, are well preserved, and offer clear evidence of prolacertiform affinities. Nineteen species of prolaeertiform have been described. Their affinities are difficult to resolve because available specimens for many of the taxa are incomplete. A series of cladistic analyses shows the existence of a tanystropheid clade (Tanystropheus, Tanytrachelos), to which are allied Cosesaurus, Malerisaurus, Boreopricea, and Macrocnemus as successive outgroups. A new synapomorphy of prolacertiforms may be the tight association of astragalus, calcaneum, centrale, and distal tarsal 4 in the ankle, with the centrale in contact with the tibia.