Muricopsis neraudeaui, Merle & Pacaud & Ledon & Goret, 2024

Merle, Didier, Pacaud, Jean-Michel, Ledon, Daniel & Goret, Bernard, 2024, New Cenozoic Muricidae (Mollusca: Gastropoda) from Europe, Geodiversitas 46 (15), pp. 495-551 : 504

Muricopsis neraudeaui n. sp.

( Figs 3 E-H; 25C, D)

urn:lsid:zoobank.org:act:3804E413-7336-4510-ADC1-B1108F47EDA6

TYPE MATERIAL. — Holotype. France • Rennes Basin , Ille-et-Vilaine , Saint-Jacques-de-la-Lande; Yellow bed of the quarry; Late Miocene (lower Messinian); MNHN.F.A77746 (Néraudeau’s sample), H: 8.5 mm ( Figs 3E, F ; 25C ).

Paratypes. France • 1 spm ; same as for the holotype; MNHN.F.A77747 (Néraudeau sample, Figs 3G, H ; 25D ) • 12 spm; idem ; MNHN.F.A90516 (Néraudeau’s sample).

ETYMOLOGY. — Dedicated to Didier Néraudeau who collected and provided the material.

TYPE HORIZON. — Yellow bed of the quarry, Late Miocene (lower Messinian), see Néraudeau et al. (2002).

TYPE LOCALITY. — France, Rennes Basin, Ille-et-Vilaine, Saint-Jacques-de-la-Lande (Lilion sand pit).

DISTRIBUTION. — Only known from the type locality.

DESCRIPTION

Protoconch not preserved. Teleoconch up to 8.5 mm in height, up to 4 mm in width, biconic in profile, composed of five whorls. Moderately high spire with subcarinate whorls. Last whorl up to 69.6% of total length. Apical angle 50°. Spiral sculpture with coarse primary cords. First whorl eroded; second whorl appearance of IP; P2 more developed than P1; second to fourth whorl: no change (IP, P1 and P2). Fifth whorl (last whorl): IP, P1 to P5, P6 atrophied (on siphonal canal), ADP and MP well developed, ABP poorly developed. Secondary cords s2 and s3. On second whorl: 12-13 varices; on fourth whorl: 10-11; on fifth whorl: 9-10 varices. On spire, axial ornamentation forming marked nodules on IP, P1 and P2. P1 and P2 nodules more developed than IP nodule. On convex part of last whorl, P1 to P5 acute nodules more or less equally developed; on siphonal canal, only ADP and MP displaying nodules. Ovate aperture up to 44% of diameter and up to 72% of length of last whorl (including siphonal canal). Columellar lip narrow, entirely adherent, bearing two tubercles anteriorly. No anal sulcus; no parietal callus. Outer lip with strong internal denticles. Series of denticles including ID, D2 to D5. D1 missing. D2 stronger. Outer lip not crenulate. Siphonal canal open, up to 32% of apertural length, slightly dorsally recurved. Pseudo-umbilicus narrow.

COMPARISONS

Like Muricopsis pontileviensis n. sp., M. neraudeaui n. sp. is another very small species for the genus and is comparable to the Langhian M. pontileviensis n. sp. in size. However, M. neraudeaui n. sp. is even smaller (8.5 mm for 5 whorls instead 12-14 mm for 5.5-6 whorls). Muricopsis neraudeaui n. sp. displays a stronger sculpture formed by acute nodules on IP, P1 to P5 and ADP, MP), whereas M. pontileviensis n. sp. bears only a swelling on the varices. In addition, the secondary cords are less numerous in M. neraudeaui n. sp. (only s2 and s3 instead s1, s2, s3, s4, s5 and s 6 in M. pontileviensis n. sp.). In spite of its very small size, M. neraudeaui n. sp. bears strong columellar denticles. This is the first record of very small Muricopsis species in fossil record. Assemblages containing very small species of Muricopsis are only documented in the Recent faunas. The best examples come from the islands of São Tomé and Martinique which contain several very small Muricopsis species ( Houart 1996; Garrigues & Lamy 2019 respectively).

Figures

FIG. 3. — Spiral cords and internal denticles of the outer lip in Muricopsis pontileviensis n. sp.(A-D) and M. neraudeaui n. sp. (E-H): A, B, holotype,MNHN.F.A71120 (Dollfus coll.), Pontlevoy,Loire-et-Cher,Loire Basin,France,Middle Miocene (Langhian);C, D, paratype,MNHN.F.A77743, (Dollfus coll.), Pontlevoy;E, F, holotype, MNHN.F.A77746 (Néraudeau sample),Saint-Jacques-de-la-Lande (Ille-et-Vilaine),Rennes basin,France,Late Miocene (Messinian);G, H, paratype,MNHN.F.A77747 (Néraudeau sample), Saint-Jacques-de-la-Lande. Scale bars: 5 mm. Credits: A-D, D. Lamy; G, H, P. Loubry (MNHN/CNRS).

FIG. 25. — New species of Muricopsis Bucquoy & Dautzenberg, 1882, Favartia Jousseaume, 1880, Dermomurex Monterosato, 1890, Trubatsa Dall, 1889 and Timbellus De Gregorio, 1885: A, B, Muricopsis pontileviensis n. sp.: A, holotype, MNHN.F.A71120 (Dollfus coll.), Pontlevoy, France, Langhian; B, paratype, MNHN.F.A77743, (Dollfus coll.), Pontlevoy; C, D, M. neraudeaui n. sp.: C, holotype, MNHN.F.A77746 (Néraudeau sample), Saint-Jacques-de-la-Lande, France, Messinian;D, paratype,MNHN.F.A77747 (Néraudeau sample),Saint-Jacques-de-la-Lande;E, F, Favartia jansseni n. sp.:E, holotype,RGM.225979,Winterswijk,The Netherlands, Langhian; F, paratype,MNHN.F.A77748 (Ledon coll.),Winterswijk;G, H, Dermomurex (Gracilimurex) ligerianus n. sp.: G, holotype,MNHN.F.A33456 (Dollfus coll.), Pontlevoy; H, paratype, MNHN.F.A33457 (Dollfus coll.); I-K, Trubatsa ganensis n. sp.: I, holotype, MNHN.A90520 (Varone coll.), Gan (Tuilerie), France, Ypresian; J, paratype, MNHN.F.A90518 (Merle coll.), Gan (Tuilerie); K, paratype, MNHN.F.A90517 (Merle coll.), Gan (Tuilerie); L, T. calviniacensis n. sp., holotype,MNHN.F.A25590 (Pacaud coll.), Cauvigny (Châteaurouge),France, Lutetian; M-O, Timbellus magnificus n. sp.: M, holotype, MNHN.F.A90522 (Pacaud coll.), Baron (Sablière Heudebert), France, Bartonian; N, paratype, MNHN.F.A90525 (Schtrock coll.), Saint-Vaast-lès-Mello (Barisseuse), France, Bartonian; O, paratype, MNHN.F.A90523 (Pacaud coll.), Baron (Sablière Heudebert). Scale bars: A-L, 5 mm; M-O, 20 mm.