Jordaniella nivosa (Montagu, 1803)

Figures 68 -69

Turbo nivosus - Montagu 1803:326

Chemnitzia nivosa (Montagu) - Clark 1855

Odostomia nivosa (Montagu) - Jeffreys 1867; Marshall 1899, 1918; van Aartsen & al. 1984; Høisaeter 1986

Odostomia (Jordaniella) nivosa (Montagu) - Winckworth 1932; van Aartsen 1987

Jordaniella nivosa (Montagu) - Fretter et al. 1986; Graham 1988; Smith & Heppell 1991; Schander et al. 2003

Chrysallida nivosa (Montagu) - Peñas et al. 1996; Høisaeter 2009

Ptychostomon (Ondina) nivosum (Montagu) - Kobelt 1903

Odostomia cylindrica Alder, 1844:327 - Forbes & Hanley 1850 - 51; Jeffreys 1859

Type material: BMNH (Montagu’s type, with “nivosus ” in his handwriting, is still preserved in the British Museum, Jeffreys 1867:117) .

Type locality: Devonshire, Great Britain (Peñas et al. 1996)

Material seen: Norway - Hordaland, 19 spms.

Diagnosis: Shell: (Figure 68) small (max. 2.1 mm), almost cylindrical. Suture channeled. Sculpture restricted to one or two spiral grooves, just above the suture, in addition to rather coarse prosocline growth lines. Protoconch intorted (type B). Aperture oval. Columellar tooth weak and retracted. Soft parts: Most specimens with dark (chocolate brown) digestive gland, filling all whorls, except the body whorl. Some specimens with grayish, greatly diminished digestive gland. Colour of alcohol conserved animal, grayish yellow. Eyes distinct, fairly far apart (distance between eyes double of eye diameter). Operculum: Thin, yellowish, translucent, elongated, slightly kidney-shaped. No internal ridge visible on operculum in situ.

Biology: Not known, but in this investigation only found on the stipes of Laminaria hyperborea (with much epifauna) in a semiexposed locality, 1 to 3 m depth.

Distribution: Not previously reported from Norway. In my material 19 specimens from a rather exposed locality near Lyroddane outside Sotra (60°10’N) in 1992. Outside Norway it is recently reported from Laesø, Kattegat (Olesen 2005), but not yet recorded from Sweden. It is further recorded from the Scottish North Sea coast (McKay & Smith 1979), Shetland, the outer Hebrides and the Scottish and British west coast, western Ireland and the south coast of the British Isles and the Channel Isles (Jeffreys 1867). Found also further south on the European Atlantic coast and occurring abundantly in the Strait of Gibraltar, but not in the western Mediterranean proper (van Aartsen et al. 1984, Peñas et al. 1996).

Remarks: Van Aartsen(1987) placed this species in Odostomia, but the molecular analyses of Schander et al. (2003) suggested that J. nivosa is closer related to Liostomia and Parthenina, and only distantly related to Odostomia s.s.