Anatomy and phylogeny of a New, Peculiar Species of Saurichthys from Monte San Giorgio (Ticino, Switzerland)

aurichthys (Actinopterygii, Osteichthyes) is an iconicTriassic genus, characterized by a highly specialized morphology. Over 40 species of this ambush predator are known from marine and freshwater localities worldwide. Of these, six species have been previously described from marine Middle Triassic beds of the UNESCO World Heritage Site Monte San Giorgio (Canton Ticino, Switzerland and Lombardy, Italy). Recent, systematic excavations in a newly-discovered, fossiliferous interval of the Meride Limestone (Sceltrich beds, Ladinian), brought to light several new specimens of Saurichthys. The material includes complete individuals, mostly belonging to a new species with a peculiar anatomy. The new species resembles Saurichthys curionii, known only from older beds of Monte San Giorgio, in many characters, but it is clearly distinct from the latter in several features. The new species is characterized by unsegmented paired and unpaired fins with branched lepidotrichia, presence of ossified haemal spines in the whole axial skeleton, and diamond-shaped mid-lateral scales. A cladistic analysis is presented to reveal the interrelationships of the new species from the Sceltrich beds.