Crenilabium exile ( Jeffreys, 1870 )

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 : 79

Crenilabium exile ( Jeffreys, 1870)

Fig. 18 g–i

Actaeon exilis Jeffreys, 1870 (p. 85).

Actaeon exilis Jeffreys—Hidalgo 1917 (p. 114).

Crenilabrum exilis ([Forbes] Jeffreys, 1870)— Nordsieck 1972 (p. 8, pl. O I, fig.).

Lissactaeon exilis (Jeffreys) — Di Geronimo & Panetta 1973 (p. 89, pl. 1, fig. 13).

Crenilabium exile (Jeffreys, 18970 ex Forbes ms.)— Smriglio & Mariottini 1996 (p. 187, figs. 8–9); Repetto et al. 2005 (p. 254, mid right fig.).

Crenilabrum [sic] exile ( Jeffreys, 1870) — Beck et al. 2006 (p. 92, top fig.).

Diagnostic characters. Elongately oval, high-spired shell; drop-shaped aperture; markedly prosocyrt external lip; thin parietal callus; slightly twisted columella; curved growth lines; fine, slightly wavy spiral striation. Protoconch: heterostrophic, blunt; 1 visibile whorl; diameter about 690 µm; surface smooth; transition to the teleoconch marked by a narrow prosocline furrow.

Remarks. Acteon nitidus Verrill, 1882 is currently regarded as a junior synonym of the present taxon (CLEMAM 2016).

Occurrence. Box-corer samples BC04 (1 specimen), BC67 (1), BC72 (1); cores BC04 (2), BC05 (6), BC21 (3), BC51 (9), BC52 (1), BC72 (1). Maximum height: 6.5 mm.

Distribution and habitat. Crenilabium exile is distributed from the northern Atlantic southward to the Caribbean and the Azores and throughout the Mediterranean, at bathyal depths ( Jeffreys 1870; Nordsieck 1972; Poppe & Goto 1991; Di Geronimo et al. 2001; Galil 2004). Among the bathyal faunas of Taranto, it was ascribed to the Abra-Nucula biocoenosis ( Di Geronimo & Panetta 1973).

Fossil record. Pliocene of northern Italy ( Tabanelli 2008).

Figures

FIGURE 18. a – c: Turbonilla micans (Monterosato, 1875), sample BC 51, scale bars: 0.5 mm (a), 0.2 mm (b – c, protoconch); d – f: Graphis gracilis (Monterosato, 1874), sample BC 72, scale bars: 0.5 mm (d), 0.2 mm (e – f, protoconch); g – i: Crenilabium exile (Jeffreys, 1870), samples BC 67 (g) and BC 04 (h – i), scale bars: 2 mm (g), 0.2 mm (h – i, protoconch); j – l: Japonacteon pusillus (MacGillivray, 1843), sample BC 72, scale bars: 2 mm (j), 0.2 mm (k – l, protoconch); m – o: Callostracon thyrrenicum (Smriglio & Mariottini, 1996), sample BC 71, scale bars: 1 mm (m), 0.2 mm (n – o, protoconch).