Chrysallida flexuosa ( Monterosato, 1874 )

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 : 76

Chrysallida flexuosa ( Monterosato, 1874)

Fig. 17 n–o

Odostomia flexuosa Monterosato, 1874 (p. 267).

Odostomia flexuosa Jeffreys—Jeffreys 1884 [b] (p. 355, pl. 26, fig. 10).

Chrysallida (Besla) flexuosa ([Jeffreys] Monterosato, 1874)— Nordsieck 1972 (p. 97, pl. P II, fig. 2). Chrysallida flexuosa ( Monterosato, 1874 ex Jeffreys ms.)— Cossignani et al. 1992 (fig. 190).? Chrysallida flexuosa ( Monterosato, 1874 ex Jeffreys ms.)— Repetto et al. 2005 (p. 237, mid right fig.). Chrysallida cf. flexuosa ( Monterosato, 1874 ex Jeffreys)— De Frias Martins et al. 2009 (p. 66, fig. 263). Not Chrysallida flexuosa (Jeffreys) — Van Aartsen 1977 (p. 55, fig. 25 =?).

Diagnostic characters. Thin ovate shell; teleoconch whorls with narrow shoulder, separated by incised sutures; drop-shaped aperture; opisthocline sinuous collabral ribs; two peripheral spiral threads low on the whorls, not passing over the ribs. Protoconch: heterostrophic, obliquely immersed (coaxial); about 1.25 visible whorls; diameter about 360 µm; transition to the teleoconch marked by a simple, slightly sinuous lip.

Remarks. Chrysallida flexuosa is herein identified according to the original description given by Monterosato (1874) and that of Micali & Nofroni (2004). Van Aartsen (1977) described C. flexuosa as possessing orthocline ribs and many spiral threads, thus probably misidentifying the specimens he had at hand.

Occurrence. Cores BC21 (2 specimens), BC51 (4), BC67 (2). Maximum height: 1.5 mm.

Distribution and habitat. Chrysallida flexuosa ranges from the northeastern Atlantic to Cape Verde and the Azores and all across the Mediterranean; it is a bathyal species sometimes found on seamounts and knolls ( Nordsieck 1972; Di Geronimo et al. 2001; Galil 2004).

Fossil record. None recorded.

Figures

FIGURE 17. a – c: Mathilda cochlaeformis Brugnone, 1873, samples BC 71 (a) and BC 66 (b – c), scale bars: 2 mm (a), 0.2 mm (b – c, protoconch); d – g: Mathilda coronata Monterosato, 1875, sample BC 71, scale bars: 2 mm (d), 0.2 mm (e – g, protoconch); h – j: Eulimella scillae (Scacchi, 1835), sample BC 72, scale bars: 1 mm (h), 0.2 mm (i – j, protoconch); k – m: Eulimella unifasciata (Forbes, 1844), sample BC 72, scale bars: 2 mm (k), 0.2 mm (l – m, protoconch); n – o: Chrysallida flexuosa (Monterosato, 1874), sample BC 67, scale bars: 0.5 mm (n), 0.2 mm (o, protoconch); p – r: Liostomia sp., sample BC 72, scale bars: 1 mm (p), 0.2 mm (q – r, protoconch).