Nucellopsis parisiensis n. sp.

(Figs 23 A-F; 28F, G)

urn:lsid:zoobank.org:act: 36606EEC-3983-4334-8A8C-E7FAF7894FEE

Muricopsis depauperatus – Cossmann & Pissarro 1911: fig. 169bis-2 [non Deshayes, 1865]. Muricopsis sp. non depauperata – Merle in Le Renard & Pacaud 1995: 114, réf.: GA 169bis-2.

Nucellopsis dudariensis – Merle 2005c [non Strausz, 1966].

TYPE MATERIAL. — Holotype. France • Paris Basin, Val d’Oise, Saint-Witz (Le Guépelle); Sable du Guépelle (biozone NP16); middle Eocene (early Bartonian, Auversian); MNHN.F.R64955 (Merle coll.), figured specimen in Merle (2005c: fig. 2H), H: 21.5 mm (Figs 23E, F; 28F). Paratypes. France • 1 spm; same as for the holotype; MNHN.F.A71797 (Pons coll.), figured specimen in Merle (2005c: fig. 1G) • 1 spm; idem; MNHN.F.A71798 (Pons coll.), figured specimen in Merle (2005c: fig. 1H, I) • 1 spm; idem; MNHN.F.J02585 (Cossmann coll.); figured in Cossmann & Pissarro (1911: pl. 36 fig. 169bis-2) • 1 spm; idem; MNHN.F.A90963 (Faullummel coll.) (Figs 23C, D; 28G) • 1 spm; idem; MNHN.F.A90964 (Faullummel coll.) (Fig. 23A, B) • 6 spm; idem; MNHN.F.A90962 (Faullummel coll.). ADDITIONAL MATERIAL. — France • 1 spm; Paris Basin, Val d’Oise, Saint-Witz (Le Guépelle); Sable du Guépelle (biozone NP16); early Bartonian; MNHN.F.A27771 (Pacaud coll.) • 1 spm; Paris Basin, Val d’Oise, Auvers-sur-Oise (Bois-le-Roi); idem; MNHN.F.A27770 (Pacaud coll.) • 1 spm; Paris Basin, Aisne, Nogent-l’Artaud; idem; MNHN.F.A90565 (Margerie coll.) • 1 spm; Paris Basin, Aisne, Bézu-le-Guéry; idem;MNHN.F.A90825 (Faullummel coll.) • 1 spm; Paris Basin, Aisne, Mont-Saint-Martin; idem; MNHN.F.J07787 (UMPC coll.) • 1 spm; Paris Basin, Seine-et-Marne, Sainte-Aulde (Caumont); idem; MNHN.F.A90826 – (Faullummel coll.) • 1 spm; Paris Basin, Seine-et-Marne, Luzancy; idem; MNHN.F.A90827 (Faullummel coll.) • Paris Basin, Oise, Loisy; idem; MNHN.F.A90828 (Faullummel coll.).

ETYMOLOGY. — From the Latin adjective parisiensis, the geographic origin of this species being the Paris Basin.

TYPE HORIZON. — Sable du Guépelle (biozone NP16, see Gély & Lorenz (1991: pl. 1), middle Eocene (early Bartonian, Auversian).

TYPE LOCALITY. — France, Paris Basin, Val d’Oise, Saint-Witz (Le Guépelle), INPN (2024).

DISTRIBUTION. — Paris Basin (France), middle Eocene (early Bartonian, Auversian).

DESCRIPTION

Smooth, multispiral protoconch of up to 2.5 whorls (see Merle 1999: pl. 23, fig. 5, holotype). Biconic teleoconch, up to 21.5 mm in height, up to 14 mm in width, biconic in profile and composed of six whorls. Moderately high spire with rounded or subcarinate whorls. Last whorl up to 73% of total length. Apical angle 64°. Spiral sculpture with strongly marked primary cords. First whorl: appearance of P1, s1, P2; P1 less marked than s1-P2; from second to third whorl, no addition of cord, P1 of equal strength to s1-P2; on fourth whorl, appearance of IP poorly marked. Fifth whorl: no addition of cord. Last whorl: IP (weak), P1 to P6, P6 not atrophied (on convex part of whorl), ADP, MP and ABP; s1 to s3 dominant, equal in strength to primary cords. First to second whorl: twelve varices. Third to fourth whorl: eleven varices. Fifth whorl: ten varices. Sixth whorl: nine varices. Varices more or less sublamellose. No true spine except angular point on P1. Suboval aperture up to 31% of diameter and up to 66% of length of last whorl (including siphonal canal). Columella slightly angular. Columellar lip narrow, adherent, smooth or with one tubercle. Outer lip with five or six denticles including D1 to D6. D1 appearing late in ontogeny. D6 occasional. ID missing. Siphonal canal, short, open, up to 31% of aperture length, slightly dorsally recurved. Pseudo-umbilicus deep, rather wide.

COMPARISONS

Nucellopsis ponsi Merle, 2005c differs from N. parisiensis n. sp., N. plicatilis (Deshayes, 1835) and N. dudariensis (Strauzs, 1966) by having a deeper posterior sinus and weaker spiral cords. Its columellar lip is occasionally ornamented by a weak denticle mid-columella, whereas it is usually smooth in the other three species. Nucellopsis parisiensis n. sp., N. plicatilis and N. dudariensis bear more numerous cords on the siphonal canal (MP and ABP) and more secondary cords than N. ponsi . Nucellopsis parisiensis n. sp. differs from N. plicatilis by the appearance of P1 and s1 on the first teleoconch whorls, by having more angular teleoconch whorls, and by usually lacking D6. Both species share a multispiral protoconch. Nucellopsis parisiensis n. sp. was erroneously identified as Jsowerbya depauperata (Deshayes, 1865) by Cossmann & Pissarro (1911) in spite of numerous differences, such as a narrower shell shape, IP on the sutural ramp and a deeper anal sulcus (Merle 2005b). Merle (1999, 2005c) identified N. parisiensis n. sp. as N. dudariensis due to several similarities with the holotype of Cantharus (Pollia) dudariensis (Fig. 23G, H) from the upper Lutetian of Hungary [apical angle near 64°, subangular whorls, thick varices, poorly developed shoulder sinus, five internal denticles (D1 to D5, D6 missing), angular columella with one small tubercle]. These similarities suggest that N. parisiensis n. sp. and N. dudariensis are closely related. However, close examinaton of the holotype of N. dudariensis (Fig. 23G, H) reveals several differences with the Parisian species, such as the late appearance of s1 on the last whorl, s1 less coarse than the primary cords P1 and P2, fewer secondary cords (only s1 instead s1 to s3), and the stronger development of IP.