Chrysallida sublustris ( Friele, 1886 )

Høisaeter, Tore, 2014, The Pyramidellidae (Gastropoda, Heterobranchia) of Norway and adjacent waters. A taxonomic review, Fauna norvegica 34, pp. 7-78 : 23

Chrysallida sublustris ( Friele, 1886)

Figures 25-26

Odostomia sublustris Friele, 1886:29 Odostomia sublustris Friele - Friele & Grieg 1901 ; Grieg 1915;

Høisaeter 1986 Chrysallida (Odostomella) sublustris (Friele) - Nordsieck 1972 Chrysallida sublustris (Friele) - Warén 1991; Micali et al. 1993;

Schander 1995; Høisaeter 2009 Turbonilla (s.str.) sublustris (Friele) - Kobelt 1903

Type material: Several syntypes ZMBN 21612 , 21613 , 21614 (see Micali et al. 1993) .

Type locality: Norwegian continental slope, off NW Norway, 640-1187 m .

Material seen: Norway – Lower slope off Norway, between 62° and 63°N, 9 spms, 1 shell .

Diagnosis: Shell: Semitransparent, glossy of a greenishyellow hue. Cyrtoconoid to conical, with distinctly convex whorls. Maximum shell length 3.1 mm. Growth lines nearly orthocline. Sculpture consisting of shallow and wavy axial ribs fading away on the lower part of the body whorl. No spiral sculpture. Columellar tooth is barely visible. Protoconch large, smooth and glossy. Soft parts: Eyes black, fairly large with distance between double the diameter. Operculum: Not studied.

Biology: Not known.

Distribution: Norwegian Sea and lower slope off Norway. Until recently recorded only a few times. Friele (1886) reported it from three stations 66° 640 m, 68° 1150 m, and 69° 1187 m. Grieg (1915) reported a single specimen from the slope outside ‘Tampen’ (62°15’N, 0°15’E, 800 m). Warén (1991) added two shells from south of Jan Mayen and one shell from northeastern Iceland. Warén (1993) reported it from two stations on the slope north of the Faroes, while Schander (1995) reported it from seven BIOICE stations in the Norwegian Sea north and east of Iceland. In my material nine specimens from five stations, all on the slope at negative temperatures, 62°31.5’N, 701 m, one specimen; 62°12’N, 708 m, three specimens; 63°10’N, 830 m, one specimen; and 63°13’N, 1003 m, three specimens. So far only reported from negative temperature water masses from the continental slopes around the Norwegian Sea (see Høisaeter 2010).

Remarks: This species is little known, and only occasionally mentioned in the literature. It is apparently not closely related to any of the other pyramidellids from our region. Three different generic designations have been proposed for it, none of them satisfying. The original designation to Odostomia by Friele was correct enough according to the system used by him, but the attempts to transfer it to Turbonilla (by Kobelt 1903) or to Chrysallida (or Odostomella, Nordsieck 1972) lack factual support. The species’ closest congeners must probably be sought among species known from Arctic waters, maybe Menestho or Aartsenia .