A revision of the early jurassic ichthyosaur hauffiopteryx (Reptilia: Ichthyosauria), and description of a new species from Southwestern Germany

Abstract

Hauffiopteryx typicus is an Early Jurassic ichthyosaur species from Europe, for which geographically partitioned morphological variation between specimens from England and Germany has been described. We provide a complete anatomical description of the German material to address this taxonomical issue. We also identify and describe a new species of Hauffiopteryx from the southwest German Basin, Hauffiopteryx altera sp. nov., differring from H. typicus in the morphology of the arrangement of cranial elements surrounding the external nares. A phylogenetic analysis recovers the German and English material referred to H. typicus as sister taxa, suggesting that these are indeed conspecific. H. typicus forms a monophyletic group with H. altera and a specimen from the Pliensbachian of Switzerland previously referred to Leptonectes tenuirostris but consistent with H. typicus. We conclude that Hauffiopteryx represents a valid genus, defined by a set of synapomorphies from both the skull and postcranium. Parsimony analysis recovers Hauffiopteryx as sister taxon to Stenopterygius + Ophthalmosauridae.