The Family Marginellidae Fleming 1828 in the Miocene (Tortonian) of South Piedmont (Italy), with the Description of Three New Species

Arch. Molluskenkunde | 144 | (2) | 243–258 | 4 figures | Frankfurt am Main, 21.12.2015

The family Marginellidae Fleming 1828 in the Miocene (Tortonian) of South Piedmont (Italy), with the description of three new species

(Gastropoda: Muricoidea)

Maurizio Sosso, M. Mauro Brunetti & Bruno Dell’Angelo

Abstract

This study is based on specimens of the family Marginellidae Fleming 1828 from the Mio- cene (Tortonian) of South Piedmont sites in the surroundings of Stazzano (Alessandria): Rio di Bocca d’Asino, S. Agata Fossili and Castellania. Seven species are here reported, three of which described as new (Dentimargo elusiva, Eratoidea antoniae, and “Marginella” giuntellii), three already known [Stazzania marginata (Michelotti 1847), Volvarina oblongata (Sacco 1890), and Marginella deshayesi Michelotti 1847] and one identified only at generic level Volvarina( sp.). The distribution of the genus Dentimargo is extended to the Miocene (Tortonian) of Italy. Dentimargo has a wider distribution, and was already known from the Eocene of France and the Pliocene of Spain. Eratoidea antoniae is compared with the syntype of E. eratoformis (Hoernes & Auinger 1880) and with specimens of E. cf. eratoformis from the Pliocene of Estepona (Spain), here figured. Key words: Marginellidae, Tortonian, South Piedmont, taxonomy, new species, distribution.

Introduction

The purpose of present work is to define the family ferent shape; almost always with protoconch paucispiral; Marginellidae Fleming, 1828 from the Miocene (Tor- thick lip with or without internal denticulations, often tonian) of South Piedmont sites in the surroundings of with external varix; siphonal notch present or absent; Stazzano (Alessandria). Several studies were published the columellar lip presents two to six plications; there about this rich molluscan fauna (Bellardi & Michelotti is no operculum (Coovert & Coovert 1995; Moreno & 1840; Michelotti 1847; Bellardi & Sacco 1873-1904; Burnay 1999). Bongo 1914; Caprotti 1964, 2010; Robba 1968), but the The habitat of Marginellids is of wide range, from systematic is often related to old works and taxa are cor- the lower intertidal zone to more than 1000 m depth, related to species of different age, furthermore several and from rocky reefs to soft bottom, the feeding habits small species are frequently incorrectly determined. are not well known, but belike they feed in wide range The family Marginellidae is characterized by a shell of animal food, with high selectiveness; one species of variable dimensions, from small to very large, shell has been observed parasitizing sleeping fishes B( ouchet size is often very valuable as a species-level character; 1989) and two other living in the sand are drilling the painted in various colours, with or without spots of dif- small bivalves and feed on their flesh P( onder 1998).

Authors’ addresses Maurizio Sosso, Via Bengasi 4/4, I-16153 Genova; E-mail: [email protected] M. Mauro Brunetti, Via 28 Settembre 1944 n. 2, I-40036 Rioveggio (Bologna); E-mail: [email protected] Bruno Dell’Angelo, Museo di Zoologia, Via Selmi 3, I-40126 Bologna; E-mail: [email protected]