Rissoa parva ( da Costa, 1778 )

Rissoa parva ( da Costa, 1778) View in CoL

( Fig. 9B View FIG 1-B View FIG 3 View FIG )

Turbo parvus da Costa, 1778: 132, fig. 4.

Rissoa parva View in CoL –Harmer 1920: 630, pl. 51, figs 11, 12. — Símonarson et al. 1998: 31, figs 12d, 15. — Raad et al. 2013: 57, figs 31-32.

Rissoa (Turboella) parva View in CoL – Van Regteren Altena et al. 1954: 13, pl. 4, fig. 42.

Turboella (Turboella) parva View in CoL – Cuerda Barceló 1987: 208, pl. 16, fig.26.

MATERIAL AND DIMENSIONS. — Maximum height 2.4 mm, width 1.1 mm. — RGM.1364991 (89), leg. ACJ ; RGM.1365260 (1), leg. ACJ ; RGM.1365035 (7), leg. AWJ ; RGM.1365094 (60), leg. AWJ .

SPECIES CHARACTERISATION. — Small elongated rissoiform shell. Up to six convex teleoconch whorls. Sculpture only on the three last whorls of around eight axial ribs separated by wider interspace. Base smooth. Aperture pyriform; columella oblique; imperforate.

DISTRIBUTION. — Lower Pliocene: NSB, Coralline Crag, England (Harmer 1920). — Lower and Upper Pleistocene: British Isles (Harmer 1920). — Lower Pleistocene: Atlantic, Greenland ( Símonarson et al. 1998), Selsoif, NW France (this paper). — Upper Pleistocene to Holocene: Netherlands (Van Regteren Altena et al. 1954; Raad et al. 2013). — Holocene: NSB (Harmer 1920; Strand Petersen 2004). Today, this species is present along the entire European Atlantic coast, Norway ( Christie et al. 2003), North Sea ( Ziegelmeier 1966; de Bruyne 1991), entire Mediterranean and into the Aegean ( Öztürk et al. 2014) and Black Sea ( Öztürk et al. 2014).

REMARK

This species shows large morphological variations in the shape, size and whorl profile, as well as ornamentation (from smooth to strongly ribbed on the three last whorls).