Akritogyra conspicua (Monterosato, 1880)

Negri, Mauro Pietro & Corselli, Cesare, 2016, Bathyal Mollusca from the cold-water coral biotope of Santa Maria di Leuca (Apulian margin, southern Italy), Zootaxa 4186 (1), pp. 1-97 : 58

Akritogyra conspicua (Monterosato, 1880)

Fig. 13 a–c

Cyclostrema conspicuum Monterosato, 1880 [a] (p. 66).

Cyclostrema valvatoides Forbes—Di Geronimo & Bellagamba 1985 (pl. 2, figs. 1–2). Akritogyra conspicua (Monterosato, 1880) —Warén 1991[a] (p. 163, figs. 14 C–D, 15 D–F); Giannuzzi-Savelli et al. 1994 (p. 104, fig. 345); Repetto et al. 2005 (p. 90, bottom left fig.).

Diagnostic characters. Depressed trochiform, thin shell; flattened spire; large rounded aperture; moderately wide umbilicus; smooth outer surface. Protoconch: very low-spired; 1.25 whorls; diameter about 300 µm; smooth surface (poorly preserved); transition to the teleoconch marked by a thin lip.

Occurrence. Cores BC05 (1 specimen), BC51 (1). Maximum height: 1.5 mm.

Distribution and habitat. Akritogyra conspicua is an endemic Mediterranean species, found in both the western and the eastern basins between 100 and 2400 m depth, sometimes in proximity of cold seeps (Warén 1991[a]; Pons-Moyà & Pons 2000; Galil 2004; Ritt et al. 2011).

Fossil record. Pleistocene ( Upper Glacial ) of Sardinia ( Di Geronimo & Bellagamba 1985).

Figures

FIGURE 13. a – c: Akritogyra conspicua (Monterosato, 1880), sample BC 05, scale bars: 0.5 mm (a – b), 0.1 mm (c, protoconch); d – f: Epitonium tiberii (de Boury, 1889), sample BC 66, scale bars: 0.5 mm (d), 0.1 mm (e – f, protoconch); g – i: Alvania cimicoides (Forbes, 1844), sample BC 72, scale bars: 1 mm (g), 0.1 mm (h – i, protoconch); j – l: Alvania testae (Aradas & Maggiore, 1844), sample BC 72, scale bars: 0.5 mm (j), 0.1 mm (k – l, protoconch); m – o: Benthonella tenella (Jeffreys, 1869), sample BC 04, scale bars: 0.5 mm (m), 0.1 mm (n – o, protoconch).