Ondina divisa nobilis (G.O. Sars, 1878 )

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

Ondina divisa nobilis (G.O. Sars, 1878)

Figure 76-77

Auriculina insculpta var. nobilis G.O. Sars, 1878:204 Odostomia insculpta var. laevissima (G.O. Sars) ? - Marshall 1893, 1900

Type material: Syntype ZMON-D1116 .

Type locality: Hasvik , western Finnmark, northern Norway .

Diagnosis: Shell: Shell large, reported to reach 4.6 mm, conical with moderately convex whorls and fairly deep sutures. Sculpture of rather fine spiral grooves separated by broader interspaces, most distinct on lower half of each whorl but weaker grooves present also on rest of whorl. Soft parts: Not known. Operculum: Not known.

Distribution: Apparently endemic to northern Norway.

A number of specimens in my material from northern Norway do not fit the description of O. divisa , nor of O. coarctata , the only other spirally lirated Ondina known from the northern coast of Norway. The variety of O. divisa from Hasvik in western Finnmark which G.O. Sars (1878) called Auriculina insculpta var. nobilis (Figure 76) is similar to these specimens. This variety has not been mentioned in the literature since. A possible exception is Marshall (1893 and 1900) who introduced a ‘var. laevissima G.O. Sars’, a name I could not find referred to in G.O. Sars (1878). The term ‘ laevissima ’ is however used in G.O. Sars’ latin diagnosis of the variety. According to the diagnosis in G.O. Sars, the variety is larger (reaching 4.6 mm in length), with deeper suture and much finer spirals distributed over most of the shell (not just the basal part). The syntype illustrated in Figure 76 and 77, is broadly conical, not rather cylindrical as the specimen of O. divisa from northern Norway shown in Figure 73. The spiral incisions on the lower half of the shell are also less concspicuous than in the specimen in Figure 73. Altogether the morphological peculiarities are too few to proclaim this a separate species, although future studies of living specimens might certainly justify a reevaluation of its specific status.