| Helveticosauridae | |
|---|---|
 | |
| Eusaurosphargis dalsassoi PIMUZ A/III 4380 | |
Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Clade: | Archosauromorpha (?) |
| Family: | †Helveticosauridae Peyer,1955 |
| Genera | |
Helveticosauridae is anextinctfamily ofbasalmarine reptiles known from theMiddle Triassic (Anisian-Ladinian boundary) of southernSwitzerland and northernItaly.[1][2]
Thetype species of the family isHelveticosaurus zollingeri, named byBernhard Peyer in 1955 based on a single nearly complete specimen T 4352 collected at Cava Tre Fontane from the Anisian-Ladinian boundary ofMonte San Giorgio, Switzerland. Peyer (1955) considered the species to be a very distinctive member of the orderPlacodontia, and thus erected Helveticosauridae as well as thesuperfamily Helveticosauroidea to contain it within Placodontia.[1]
Nosotti and Rieppel (2003) describedEusaurosphargis from the equivalent beds at Cava di Besano of theBesano Formation (Anisian-Ladinian boundary) of Italy. Theirphylogenetic analysis recovered it as thesister taxon ofHelveticosaurus, and thus it was assigned to Helveticosauridae. Based on the description in the literature available forSaurosphargis (whoseholotype is lost), they considered it to also fall in the Helveticosauridaeclade.[2] The anatomy ofSaurosphargis was finally clarified by comparisons with the well-preserved specimens ofSinosaurosphargis, and as a resultSaurosphargis was no longer considered to be anomen dubium, and thus could be included in a phylogenetic analysis. Liet al. (2011) foundSaurosphargis andSinosaurosphargis to form a clade separate from that ofEusaurosphargis andHelveticosaurus, thusSaurosphargis was removed from Helveticosauridae, and placed in its own familySaurosphargidae together withSinosaurosphargis.[3]
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