Trubatsa ganensis Merle, Pacaud, Ledon & Goret, 2024, n. sp.
Creators: name: Merle, Didier
name: Pacaud, Jean-Michel
name: Ledon, Daniel
name: Goret, Bernard
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Neogastropoda
Muricidae
Trubatsa
Trubatsa ganensis

description: Trubatsa ganensis n. sp.
(Figs 5 A-D; 25I-K)
urn:lsid:zoobank.org:act: 0EBD7F4D-8646-456B-BD5C-10FA4A8625DD
Trubasta [sic] parisiensis – Merle 1990: 169, pl. 3, figs 13-15, pl. 4, fig. 12 [non d’Orbigny, 1850].
TYPE MATERIAL. — Holotype. France • Aquitaine Basin, Pyrénées-Atlantiques, Gan (Tuilerie); Uppermost part of the Marnes de Gan only (top biozone N12/base biozone NP13); Early Eocene (Ypresian); MNHN.F.A90520 (Varone coll.), H: 17 mm (Figs 5A, B; 25I).
Paratype. France • 1 spm; same as for the holotype; MNHN.F.R61441 (Merle coll., figured specimen of Merle (1990: pl. 3, fig. 13) • 1 spm; idem; MNHN.F.A90518 (Merle coll., with complete siphonal canal, Figs 5C; 25J) • 1 spm; idem; MNHN.F.A90517 (Merle coll. with incomplete siphonal canal; Figs 5D; 25K) • 12 spm; idem; MNHN.F.A90519 (Merle coll.) • 17 spm; idem; MNHN.F.A72383 (Varone coll.).
ADDITIONAL MATERIAL. — 4 spm; idem;MNHN.F.A90521 (Combault coll.).
ETYMOLOGY. — From the type locality, Gan (Pyrénées-Atlantiques).
TYPE HORIZON. — Uppermost part of the Marnes de Gan only (top biozone N12/base biozone NP13), see Nolf et al. (2002: 173, fig. 4), Early Eocene (Ypresian).
TYPE LOCALITY. — France, Aquitaine Basin, Pyrénées-Atlantiques, Gan (Tuilerie) (Merle 1986: 8; Nolf et al. 2002: 185, 186).
DISTRIBUTION. — Only known from the type locality.
DESCRIPTION
Bulbous protoconch of 1.5-2 whorls (see Merle 1990: pl. 4, fig. 12). Teleoconch up to 17 mm (canal siphonal not complete) in height, up to 11 mm in width, biconic in profile, composed of five whorls. Moderately high spire. Last whorl representing 72% of total height. Spiral angle 56°. Suture weakly impressed. Axial sculpture consisting in four slightly foliate varices per whorl. On spire, anal tube (P1) and very short spine (P2). Anal tube forming angle of approximately 60-65° with axis of shell. Anal tube (P1) totally integrated within varices, eliminating shoulder. Small callus at base of anal tube. On convex part of last whorl and abapically to anal tube four spinelets (P2, s2, P3, P4 and P5). Intervarical spaces usually smooth, but with P3-P5 cords on holotype. Rounded aperture up to 25% of diameter, up to 74% of height of last whorl (including siphonal canal). Edge, erect, smooth, peristome complete. Siphonal canal closed, usually broken, occupying 60% of apertural lenght (complete siphonal canal longer, see Fig. 5C).
COMPARISONS
Merle (1990: 169) attributed this material collected at Gan to Typhis parisiensis d’Orbigny, 1850 and to the genus Trubatsa Dall, 1889. The generic attribution is correct and the distinction between Siphonochelus Jousseaume, 1880 and Trubatsa is now validated by molecular data (Houart et al. 2021). Nevertheless, after further comparison, specific attribution of the Gan material to this species incorrect. Firstly, the protoconchs are different, that of T. ganensis n. sp. is paucispiral (Merle 1990: pl. 4, fig. 12) and that of T. parisiensis is multispiral (see juvenile specimen from Barton illustrated by A. Morton (2023; www.dmap.co.uk/fossils). In addition, the Bartonian specimens are more sculptured than the specimens from Gan (Fig. 5E, F). They display stronger spines (P2 to P5) and P6, spiral cords (P2 to P5) in the intervarical spaces and a partition recalling that of T. gaasensis (Tournouër in Benoist, 1880) from the Rupelian of Aquitaine Basin. Trubatsa parisiensis occur in the Bartonian from England and in the Priabonian from Germany (von Koenen 1889). Merle (1985) also suggested that Typhis sinuosus Cossmann, 1902 from the Bartonian of Bois-Gouët (France, Loire-Atlantique) was a junior subjective synonym of T. parisiensis. According to Merle (1985), the shape of the varices of the type specimen (Dumas coll.) of T. sinuosus recalls that of Trubatsa. However, it is a juvenile (H: 8 mm) and the varices of the juveniles of Typhina rutoti Cossmann, 1882 are also similar. Moreover, the type specimen of T. sinuosus is worn, lacks a protoconch and finally lacks diagnostic characters. Thus, we consider T. sinuosus as a nomen dubium.
description: Published as part of Merle, Didier, Pacaud, Jean-Michel, Ledon, Daniel & Goret, Bernard, 2024, New Cenozoic Muricidae (Mollusca: Gastropoda) from Europe, pp. 495-551 in Geodiversitas 46 (15) on page 508, DOI: 10.5252/geodiversitas2024v46a15, http://zenodo.org/record/13985760