Manzonia crassa
Creators: name: Bouchard, Blanche
name: Wesselingh, Frank P.
name: Pouwer, Ronald
name: Landau, Bernard
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Littorinimorpha
Rissoidae
Manzonia
Manzonia crassa

description: Manzonia crassa (Kanmacher, 1798)
(Fig. 8D 1-D 3)
Turbo crassus Kanmacher 1798: 638, fig. 20.
Manzonia (Manzonia) costata – Cuerda Barceló 1987: 202, pl. 16, fig. 18.
Manzonia crassa – Chirli & Linse 2011: 83, pl. 24, fig. 4. — Van Dingenen et al. 2016: 140, pl. 10, fig. 2. — Landau et al. 2018: 274, pl. 103, fig. 1.
For more, see synonymy list in Van Dingenen et al. (2016) and Landau et al. (2018).
MATERIAL AND DIMENSIONS. — Maximum height 1.7 mm, width 1.0 mm. RGM.1364988 (4), leg. ACJ; RGM.1365201 (1), leg. ACJ; RGM.1365093 (16), leg. AWJ.
SPECIES CHARACTERISATION. — Shell small, rissoiform. Protoconch not preserved. Four strongly convex teleoconch whorls separated by deeply impressed suture; sculpture of numerous, regular, flattened spiral cords; about ten high, widely spaced, sinuous, prosocline axial ribs. Ribs stop abruptly at strong, elevated peribasal cord; base narrow, deeply concave forming wide groove between peribasal cord and peristome. Aperture ovate, outer lip strongly thickened by rounded labial varix, peristome complete.
DISTRIBUTION. — Middle Miocene: Atlantic, Loire Basin, France (de Morgan 1915; Cossmann 1918; Glibert 1949); Paratethys, Austria (Kowalke & Harzhauser 2004), Hungary (Strausz 1966), Poland (Friedberg 1923; Bałuk 1975), Romania (Kowalke & Harzhauser 2004); Proto-Mediterranean, Karaman Basin, Turkey (Landau et al. 2013). — Upper Miocene: Atlantic, NW France (Calas 1949; Landau et al. 2018); Proto-Mediterranean, Italy (Sacco 1895; Venzo & Pelosio 1963). — Lower Pliocene: Atlantic of NW France (Van Dingenen et al. 2016); central Mediterranean, Italy (Chirli 2006), Tunisia (Fekih 1975). — Upper Pliocene: Atlantic, Portugal (Silva 2001); western Mediterranean, Spain (Landau et al. 2004); central Mediterranean, Italy (Sacco 1895; Malatesta 1974; Cavallo & Repetto 1992; Sosso & dell’Angelo 2010; Tabanelli et al. 2011). — Lower Pleistocene: NSB, British Isles (Harmer 1918); Atlantic, Selsoif, NW France (this paper); western Mediterranean of France (Glibert 1962); central Mediterranean, Italy (Cerulli-Irelli 1914; Buccheri 1970); eastern Mediterranean, Rhodes Island (Chirli & Linse 2011). — Upper Pleistocene: NSB, the Netherlands (Van Regteren Altena et al. 1954; Raad et al. 2013); western Mediterranean, Balearic Islands (Cuerda Barceló 1987). Today this species occurs in the northeastern Atlantic from Norway southwards to Morocco, entire Mediterranean, from extreme low tide line to 50 m depth, often on sandy bottoms, but also under stones and in weeds (Poppe & Goto 1991).
REMARKS
For discussion on fossil populations, see Landau et al. (2013: 74) and Van Dingenen et al. (2016: 140).
description: Published as part of Bouchard, Blanche, Wesselingh, Frank P., Pouwer, Ronald & Landau, Bernard, 2025, The Gelasian gastropod fauna of Selsoif (Manche, France), pp. 39-91 in Geodiversitas 47 (3) on page 60, DOI: 10.5252/geodiversitas2025v47a3, http://zenodo.org/record/14823602