Medorippe ampla Garassino, De Angeli, Gallo & Pasini, 2004

Fig. 2B

Medorippe ampla Garassino, De Angeli, Gallo & Pasini, 2004: 260-262, figs. 5, 6a, b.

Medorippe ampla – De Angeli & Garassino 2006: 40. — De Angeli et al. 2009: 174, fig. 6. — Schweitzer et al. 2010: 79.

Material and measurements: Two carapaces in dorsal view (MSF 2301 – lcxp: 14 mm, wcxp: 15 mm; MSF 2317 – lcxp: 15 mm, wcxp: 16 mm).

Discussion. Though both specimens are preserved as moulds of the interior, some main proxy characters of the carapace of one specimen (MSF 2317) allow us to assign them to Medorippe Manning & Holthuis, 1981, in having a subhexagonal convex carapace; divergent anterolateral margins; sinuous posterior margin, slightly convex at the intestinal margin; dorsal regions well marked by grooves; deep cervical groove joining branchial grooves laterally; sinuous branchial grooves joining groove dividing urogastric from cardiac region; and well-developed hepatic regions. Moreover, the carapace is wider than long, the narrow front with two short lobes, the well-developed and elongate extraorbital teeth and the presence of (?granulate) carinae on hepatic, branchial, and supraorbital regions, are all peculiar characters that distinguish Medorippe ampla from the extant and fossil type species M. lanata, reported from the Pleistocene of Sicily (Gemmellaro, 1914) (Garassino et al., 2004: 262). Based on these distinctive characters the studied specimens are confidently ascribed to M. ampla Garassino, De Angeli, Gallo & Pasini, 2004 .

Medorippe ampla was previously reported from the late Miocene (Messinian) of Cocconato (Asti, Piedmont) and from the Rio Popogna (Livorno, Tuscany) (Garassino et al., 2004; De Angeli et al., 2009).