Simolestes (meaning "snub-nosed thief") is an extinct pliosaurid genus that lived in the Middle to Late Jurassic.[R. Lydekker. 1877. Notices of new and other Vertebrata from Indian Tertiary and Secondary rocks. Records of the Geological Survey of India 10(1):30-43] but the referral of this species to Simolestes is dubious.[Godefroit, P. (1994). Simolestes keileni sp. nov., un Pliosaure (Plesiosauria, Reptilia) du Bajocien supérieur de Lorraine (France). Bulletin des Académie et Société Lorraines des sciences, , 1994, tome 33, n°2, p. 77-95. 33. .]
Description
Simolestes possessed a short, high, and wide skull which was built to resist torsional forces when hunting.
The largest specimens of S. vorax reached approximately in length, if a head to body ratio similar to Liopleurodon is applied.
Palaeobiology
Like most pliosaurs,
Simolestes possessed
salt glands, which would have enabled the animal to maintain salt balance and drink seawater.
[Noè, L. F. (2001). A taxonomic and functional study of the Callovian (Middle Jurassic) Pliosauroidea (Reptilia, Sauropterygia). Chicago] Recent studies on
plesiosaur locomotion indicate that
Simolestes, like other plesiosaurs, possessed a unique bauplan for movement, which differs from modern organisms in similar niches.
Feeding habits
Simolestes's exact feeding habits are unclear. The current consensus, however, is that the genus was primarily teuthophagous, consuming belemnites, soft
squid and
ammonites. It is possible
Simolestes was also ecologically separated from other contemporary pliosaur genera such as
Liopleurodon and
Pachycostasaurus by hunting in deeper waters or at night, as modern cephalopods exhibit diurnal feeding cycles, spending daylight in deeper, safer waters, and rising at night to feed.
Classification
The
cladogram below follows a 2011 analysis by paleontologists Hilary F. Ketchum and Roger B. J. Benson, and reduced to genera only.
