Ondina divisa cf. rubra

Høisaeter, Tore, 2014, The Pyramidellidae (Gastropoda, Heterobranchia) of Norway and adjacent waters. A taxonomic review, Fauna norvegica 34, pp. 7-78 : 46

Ondina divisa cf. rubra

Figure 75

This form is based on eight specimens from Oseberg oilfield at 60º30’N, 106 m, on the western slope of the Norwegian Trench (and thus not strictly part of the Norwegian fauna). It is most similar to O. divisa , because of its sculpture of five or six strong spiral grooves above the suture with dense microscopic striae above that, and the shape and size of the protoconch.The main differences from O. divisa are the narrower, elongated and slightly laterally compressed, shouldered whorls (see Figure 75 ). O. warreni as described in Fretter et al. (1986), (“The four postlarval whorls are more tumid than in obliqua , often with a peripheral flattening, and the sutures are deep,…”) is quite similar, but I could find no evidence for spiral sculpture covering all of the first postlarval whorl as, according to the literature, O. warreni , should have. In addition to the narrow, conical shape, the most characteristic feature of this form is the reddish colour of the soft parts, varying from deep purple to slightly reddish yellow. This might be a reflection of the individual diet, though.

Figures

Figure 75. Ondina divisa cf.rubra, three specimens from Oseberg oilfield, 60º34.7’N, 02º48.7’E, 106 m, 3.6, 3.1 and 2.5 mm (ZMBN 83217). Figure 76. Ondina divisa nobilis. Syntype NHMO D 1116, 4.2 mm. Figure 77. Ondina divisa nobilis. From left: a specimen from Marvollvika, Bodø, (Nordland), 67°12’N, 14°35’E, 25 m, 4.05 mm (N 21-80); syntype NHMO D 1116, 4.2 mm; a specimen from Nordfjorden in Rødøy, (Nordland), 66°34.3’N 13°30.5’E, 15-11 m, 3.35 mm (N 15-84). Figure 78. Ondina warreni, a specimen from near Grimstad (Aust Agder), 58°19’N, 1.55 mm. Figure 79. Ondina warreni. The one at left from Shetland (from Warén 1991), 3.3 mm. The other three from Grønsfjorden, Lindesnes, (Vest Agder), 58°02’N, 07°03’E, 165 m, 3.5, 2.6, 2.15 mm (S 89-88). Figure 80. Ondina diaphana, from Gurskøy in Herøy (Møre og Romsdal) 62°18’N, 05°38’E, 35-30 m, 2.55 mm (ZMBN 83241).