Timbellus magnificus 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
Timbellus
Timbellus magnificus

description: Timbellus magnificus n. sp.
(Figs 7 A-F; 25M-O)
urn:lsid:zoobank.org:act: BAAFF825-EC4D-448B-A23A-DEDB085F9C53
TYPE MATERIAL. — Holotype. France • Paris Basin, Oise, Baron (Sablière Heudebert); Sables d’Auvers (biozone NP16); middle Eocene (lower Bartonian, Auversian); MNHN.F.A90522 (Pacaud coll.), H: 58.5 mm (Figs 7A, B; 25M).
Paratypes. France • 1 spm; same as for the holotype; early Bartonian; MNHN.F.A90523 (Pacaud coll.) (Figs 7E, F; 25O) • 3 spm; idem; MNHN.F.A90524 (Faullummel coll.) • 1 spm Paris Basin, Oise, Saint-Vaast-lès-Mello (Barisseuse); idem; MNHN.F.A90525 (Schtrock coll.) (Figs 7C, D; 25N) • 1 spm; Paris Basin, Aisne, Montreuil-aux-Lions; idem; MNHN.F.A73852 (Pons coll.) • 1 spm; Paris Basin, Seine-et-Marne, Isle-les-Meldeuses; idem; MNHN.F.A90526 (Faullummel coll.) • 1 spm; Paris Basin, Val d’Oise, Auvers-sur-Oise (Bois-le-Roi); idem; MNHN.F.A90527 (ex galerie de Zoologie coll.).
ADDITIONAL MATERIAL. — France • 1 spm; Paris Basin, Aisne, Bézu-le-Guéry; Sables d’Auvers (biozone NP16); early Bartonian; MNHN.F.A90528 (Faullummel coll.) • 1 spm; Paris Basin, Aisne, Baron (Sablière Heudebert); idem;MNHN.F.A90529 (Merle coll.) • 1 spm; Paris Basin, Seine-et-Marne, Le Limon; idem; MNHN.F.A90530 (Pacaud coll.).
ETYMOLOGY. — From the Latin magnificus meaning magnificent.
TYPE HORIZON. — Sables d’Auvers (biozone NP16), see Gély & Lorenz (1991, pl. 1), middle Eocene (lower Bartonian, Auversian).
TYPE LOCALITY. — France, Paris Basin, Oise, Baron (Sablière Heudebert), see Wyns (1980).
DISTRIBUTION. — Paris Basin (France), Sables d’Auvers, middle Eocene (lower Bartonian, Auversian).
DESCRIPTION
Unknown not preserved.Teleoconch up to 58.5 mm in height, up to 33 mm in width, subfusiform in profile, composed of seven whorls. Moderately high spire. Last whorl up to 85% of total length. Apical angle 71°. Spiral sculpture with moderately marked primary cords on varices. From first to fourth whorl, no spiral sculpture. Fifth whorl: appearance of weak cords corresponding to P1, P2, P3, s1 and s2; primary and secondary cords of same thickness. Sixth whorl: increase of thickness of cords. Seventh whorl: P1 to P6, s1 to s5, P6 weak; ADP, MP and ABP on siphonal canal. Axial sculpture eroded on first whorl. On second whorl, eight protovarices. On third whorl: appearance of varices; three varices and one intervarix between. From fourth to last whorl no change; intervarices low. Higher relief intervarices around on P2. Varices sublamellose on early whorls, thickened on last whorls. Appearance of short P1 spine on fourth whorl. On last whorl, short P1 spine oriented adapically; no other cord spine. Ovate aperture up to 36% of diameter and up to 70% of length of last whorl (including siphonal canal). Columellar lip smooth, narrow, slightly erect anteriorly and forming very flat curved inductura at base. Parietal lip slightly adherent. Outer lip with small denticles, ID, D1, D7 simple, D2-D6 bifid or trifid for D4. Siphonal canal narrow, open, bent, slightly dorsally recurved, up to 43% of apertural length. Pseudoumbilicus narrow.
COMPARISONS
With a length exceeding 55 mm, it is one of the largest Eocene Timbellus with T. capitaneus Pacaud, Goret & Ledon, 2017 which can exceeed a length of 65 mm. The spiral cords of T. magnificus n. sp. are weak in juvenile specimens of four whorls, whereas they are already well developed and well marked in juvenile specimens of T. capitaneus at the same growth stage. In addition, T. magnificus n. sp. bears a small and very short P1 spine oriented adapically, whereas that of T. capitaneus is strong and abaxially oriented. Moreover, T. capitaneus and T. magnificus n. sp. share a series of internal denticles including D1 to D6, but all internal denticles of T. magnificus n. sp. are bifid and more or less of the same size.
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 pages 510-511, DOI: 10.5252/geodiversitas2024v46a15, http://zenodo.org/record/13985760