Dolichosauridae Gervais, 1852

Conrad, J. L., 2008, Phylogeny And Systematics Of Squamata (Reptilia) Based On Morphology, Bulletin of the American Museum of Natural History 2008 (310), pp. 1-182 : 125

Dolichosauridae Gervais, 1852

(figs. 54F, 55F, 56D)

DEFINITION: All taxa sharing a more recent common ancestor with Dolichosaurus longicollis than with Mosasaurus hoffmanni .

DIAGNOSIS: Dolichosauridae as defined here in the context of the present analysis includes only Dolichosaurus longicollis and Aphanizocnemus , and is united by 243(2) cervical intercentra fused to the posterior part of the preceding intercentrum.

COMMENTS: Lee and Caldwell (2000) coded Dolichosauridae based on Coniasaurus and Dolichosaurus longicollis , but their analysis does not resolve the position of Aphanizocnemus with respect to their Dolichosauridae , Adriosaurus , and/or snakes. Carroll (1988b: 618) included Adriosaurus , Dolichosaurus longicollis , Eidolosaurus trauthi , and Pontosaurus in his Dolichosauridae , but placed Coniasaurus tentatively with the Aigialosauridae .

The current analysis offers no unambiguous character support for uniting Coniasaurus and Dolichosaurus longicollis . The principle trees recovered in this analysis always recover a basal position for a clade containing Dolichosaurus longicollis and Aphanizocnemus , but the relative phylogenetic placement of Coniasaurus is more problematic. Coniasaurus is recovered as the sister taxon to Dolichosaurus longicollis , as the sister taxon to all other mosasaurs, as a nested mosasauroid (above the level of adriosaurids), or as the sister-taxon to Opetiosaurus within mosasauroids. Note that the existing cranial remains are very limited in most of the basal mosasaur taxa and that Coniasaurus is known primarily from partial skulls. Future inclusion of a Judeasaurus tchernovi , recently described by Haber and Polcyn (2005), may help to resolve this problem.