Natrix sp.

Delfino, Massimo, Bailon, Salvador & Pitruzzella, Gaetano, 2011, The Late Pliocene amphibians and reptiles from “ Capo Mannu D 1 Local Fauna ” (Mandriola, Sardinia, Italy), Geodiversitas 33 (2), pp. 357-382 : 376

Natrix sp.

MATERIAL EXAMINED. — Trunk vertebra: 1.

DESCRIPTION

The fragmentary vertebra (not figured) has an elongate centrum whose length is of 3.0 mm; the parapophysis and diapophysis are separated by a depression and both distinctly protrude from the lateral wall of the centrum; the parapophyseal processes are horizontally oriented, long, rather wide and with a nearly rounded tip; cotyle and condyle are approximately circular; paracotylar tubercles are weakly developed; subcentral grooves are rather deep; the hypapophysis is present but only its basis is preserved; paracotylar, lateral, and subcentral foramina are small; the orientation of the only preserved postzygapophysis indicates that the missing prezygapophyseal facets were approximately horizontal; the neural arch is tall and its posterior border is nearly straight in posterior view; the neural canal is proportionally wide; the neural spine is nearly completely broken off.

DISCUSSION

The general proportions of the vertebra, the morphology of the paradiapophyses, the shape and proportions of the parapophyseal processes, the orientation of the pre- and postzygapophysis, the presence of a hypapophysis, and the height of the neural arch, indicate that this vertebra belongs to the genus Natrix . The absence of a complete hypapophysis and the overall poor preservation of the vertebra hinder a specific identification, despite the roundness of the parapophyseal processes could suggest the presence of N. natrix (see characters discussed by Szyndlar 1984, 1991b; Holman 1991).

Family VIPERIDAE Laurenti, 1768