Aclis minor ( Brown, 1827 )

Bouchard, Blanche, Wesselingh, Frank P., Pouwer, Ronald & Landau, Bernard, 2025, The Gelasian gastropod fauna of Selsoif (Manche, France), Geodiversitas 47 (3), pp. 39-91 : 66

Aclis minor ( Brown, 1827)

( Fig. 10D 1-D 3 )

Turritella minor Brown, 1827 : pl. 57, figs 57-58.

Aclis minor – Van Regteren Altena et al. 1955: 33, fig. 77. — Menkhorst & Wesselingh 2018: 42, figs 13, 14. — Landau & Mulder 2022: 161, figs 10a-c.

For more, see synonymy list in Landau & Mulder (2022).

MATERIAL AND DIMENSIONS. — Maximum height 1.8 mm (incomplete), width 0.6 mm. — RGM.1365077 (11), leg. AWJ ; RGM.1365257 (1), leg. AWJ .

SPECIES CHARACTERISATION. — Small, turriform shell with narrow apical angle. Protoconch absent in all specimens. About six convex teleoconch whorls separated by narrowly impressed suture. Three spiral cords on early whorls, a fourth one appearing above the suture on later whorls; aperture ovate.

DISTRIBUTION. — Upper Miocene: NSB, Denmark ( Rasmussen 1968; Schnetler 2005), Germany ( Moths 1989). — Lower Pliocene: NSB, Coralline Crag, England ( Wood 1842, 1848; Harmer 1925); central Mediterranean, Italy ( Chirli 2009; Brunetti & Cresti 2018). — Upper Pliocene: western Mediterranean, S Spain ( Landau et al. 2006; Landau & Mulder 2022). — Lower Pleistocene: NSB, England, Ireland (Harmer 1925); Atlantic, Selsoif, NW France (this paper); central Mediterranean, Italy ( Cerulli-Irelli 1914); eastern Mediterranean, Rhodes Island ( Chirli & Linse 2011). — Pleistocene (indeterminate): NSB, Netherlands ( Van Regteren Altena et al. 1955; Menkhorst & Wesselingh 2018). — Holocene: NSB ( Strand Petersen 2004). Today this species is present in the Atlantic, from the British Isles ( Guiry & Guiry 2011) to Madeira ( Segers et al. 2009) and in the Mediterranean Sea from Spain ( Peñas et al. 2009) to the Aegean Sea ( Öztürk et al. 2014), at depths of 2-250 m, on calcareous algae, sandy, or muddy bottoms ( Albanesi et al. 1981).

Figures

FIG. 10. — Gastropods from Selsoif. All illustrated specimens are collected from the Sablière du Grand Marais, Selsoif, France and come from the Early Pleistocene Saint-Nicolas de Pierrepont Formation (continuation): A, Calyptraea chinensis s.l. (Linnaeus, 1758), RGM.1365194, leg ACJ, H = 3.2 mm; B, Crepidula gibbosa Defrance, 1818, RGM.1365185, leg AWJ, H = 3.3 mm; C, Capulus ungaricus (Linnaeus, 1758), RGM.1365200, leg AWJ, H = 12 mm; D, Aclis minor (Brown, 1827), RGM.1365257, leg AWJ, H = 1.79 mm; E, Aclis walleri Jeffreys, 1867, RGM.1365001, leg ACJ, H = 2.33 mm; F, Melanella alba (da Costa, 1778), RGM.1365318, leg AWJ, H = 5.96 mm; G, Velutina aff. velutina (Müller, 1776), RGM.1365186, leg AWJ, H = 3.27 mm; H, Trivia coccinelloides (J. de C. Sowerby, 1822), RGM.1365272, leg WG, H = 7.7 mm; I, Trivia coccinelloides (J. de C. Sowerby, 1822), RGM.1365271, leg WG, H = 6.38 mm; J, Trivia coccinelloides (J. de C. Sowerby, 1822), RGM.1365203, leg WG, H = 6.7 mm. Scale bars: A, B, G, 1 mm; C, F, H-J, 2 mm; D, E, 500 μm.

FIG. 1. — Simplified geological map of the Normandy region (after Dugué et al. 2000 and Pareyn 1987) showing the location of Selsoif:1, Precambrian-Palaeozoic basement; 2, Permo-Mesozoic Paris Basin fill; 3, Neogene-Quaternary subbasins.

FIG. 3. — Simplified biographic map of South-West of Europe (after Landau et al. 2011).