Beauvoisina, Kiel & Campbell & Gaillard, 2010

Kiel, Steffen, Campbell, Kathleen A. & Gaillard, Christian, 2010, New and little known mollusks from ancient chemosynthetic environments, Zootaxa 2390 (1), pp. 26-48 : 41

Genus Beauvoisina gen. nov.

Type species: Beauvoisina carinata sp. nov., from the late Jurassic seep deposits at Beauvoisin, southeastern France .

Diagnosis: Shell very large (up to 140 mm), oval, elongate-oval, to nearly rectangular in shape; beak displaced towards posterior in more elongate specimens; sculpture of irregular commarginal ribs; lunule asymmetric, broader in right valve, bordered by ridge in each valve; escutcheon elongate-lenticular. Radial striations on interior shell surface, many of which start dorsally with a deep pit; ventral third of shell with deep commarginal grooves apparently corresponding with growth rings on shell’s exterior. Hinge with two cardinal teeth in each valve, anterior tooth smaller and vertical, posterior tooth bigger and with posteroventral orientation; nymph straight or slightly convex, slightly longer than three-fifths of length of escutcheon.

Etymology: For the type locality of the type species at Beauvoisin, southeastern France.