Ondina divisa (J. Adams, 1797 )

Ondina divisa (J. Adams, 1797) View in CoL

( Fig. 13I View FIG 1-I View FIG 3 View FIG )

Turbo divisus J. Adams, 1797: 254 .

Turbo insculptus Montagu, 1808: 129 .

Odostomia insculpta View in CoL – Wood 1872: 62, pl. 4, fig. 18.

Odostomia (Ondina) insculpta View in CoL – Harmer 1923: 839, pl. 64, fig. 20.

Evalea divisa View in CoL – Graham 1988: 566, fig. 244.

Ondina divisa View in CoL – Marquet 1997: 108, pl. 10, fig. 3.

MATERIAL AND DIMENSIONS. — Maximum height 1.1 mm, width 0.6 mm. — RGM.1365021 (1), leg. ACJ; RGM.1365266 (1), leg. AWJ ; RGM.794507 (19), leg. AWJ ; RGM.961906 (1), leg. AWJ ; RGM.1365022 (1), leg. ACJ , RGM.1365123 (6), leg. AWJ .

SPECIES CHARACTERISATION. — Elongate-ovoid shell, strongly intorted type C protoconch ( Landau et al. 2020a), teleoconch of three moderately convex whorls, separated by deeply impressed suture, opisthocline to orthocline growth-lines, sinuous towards adapical suture, fine spirals cover entire whorl, last whorl inflated, regularly convex, narrow umbilical chink. Aperture pyriform, columella bearing weak fold mid-aperture.

DISTRIBUTION. — Lower Pliocene: NSB, Coralline Crag, England ( Wood 1872); Kattendijk Formation, Belgium ( Marquet 1997). — Late Pliocene: St Erth, Atlantic, England (Harmer 1923), Selsoif, NW France (this paper). Today this species occurs in northern Europe from North Norway to the Bay of Biscay ( Fretter et al. 1986).

REMARKS

The specimens from Selsoif differ slightly from modern ones in having the spiral sculpture extending along the entire whorl surface, whereas in extant specimens it is restricted to the abapical portion of the whorl.