Rissoa curticostata Wood 1848

Rissoa curticostata Wood, 1848 (Fig. 9A 1-A 3) Rissoa curticostata Wood, 1848: 102. — Raad et al. 2013: 55, fig. 26. Rissoa semicostata – Wood 1848: 102, pl. 11, fig. 10 (non Montagu, 1803). — Harmer 1920: 634, pl. 51, fig. 16 (not fig. 17). Rissoa (Turboella) curticostata – Van Regteren Altena et al. 1954: 13, pl. 4, fig. 41. — Marquet 1997: 15, pl. 2, fig. 4. MATERIAL AND DIMENSIONS. — Maximum height 1.6 mm, width 1.0 mm. — RGM.1364990 (273), leg. ACJ; RGM.1365196 (1), leg. AWJ; RGM.1365092 (66), leg. AWJ; RGM.1364915 (4), leg. WG. SPECIES CHARACTERISATION. — Small broad rissoiform shell. Three, flattened protoconch whorls. Four teleoconch whorls. Sculpture of around 16 strong, orthocline ribs covering numerous spiral ribs. Base covered by five weak spiral cords. Umbilicus closed; aperture ovate, thick, denticulate outer lip. DISTRIBUTION. — Upper Pliocene: NSB, Red Crag, England (Harmer 1920), Belgium (Marquet 1997). — Pliocene to Lower Pleistocene (indeterminate): Netherlands (Van Regteren Altena et al. 1954; Raad et al. 2013). — Lower Pleistocene: NSB, England (Wood 1848; Harmer 1920); Atlantic, Selsoif, NW France (this paper). REMARKS Wood (1848: 102) figured this species under the name Rissoa semicostata Woodward but stressed that it was not the same species as R. semicostata Montagu, 1803 and in his discussion proposed the name R. curticostata for the Crag species. Harmer (1920: 634) argued that Woodward’s name was available because Montagu's species was a junior subjective synonym of R. striata J. Adams, 1797. However, J. Adams’s name is an unavailable basionym.