Liostomia hansgei Warén, 1991

Høisaeter, Tore, 2014, The Pyramidellidae (Gastropoda, Heterobranchia) of Norway and adjacent waters. A taxonomic review, Fauna norvegica 34, pp. 7-78 : 53

Liostomia hansgei Warén, 1991

Figures 87-89

Liostomia hansgei sp.n. - Warén 1991:108

Liostomia hansgei Warén - Peñas et al. 1996 ; Høisaeter 2009

Type material: Holotype and four paratypes, SMNH 4098 and 4099.

Type locality: Swedish west coast, Koster area, south of Lilleskär, 30-40 m, fine silt.

Material seen: Norway - Hordaland, 6 spms ; Nordland, 1 spm.

Diagnosis: Shell: Medium size, fairly solid, with deep suture. Cylindrical, colour-less, often covered by solid ferruginuous deposit, has a blunt apex and a small aperture. Soft parts: (Based on a specimen from Fanafjorden, mid-part, 145-155 m). The front of the foot strongly ciliated. On the edges of the foot and in a wide band behind the eyes, a mixture of scattered, dirty white, opaque, and somewhat bigger oily-clear, and deep purple-brown spots and blotches. A collection of larger purple-brown pigment in the heart region. Pigmentation dense and gradually more pronounced farther up on the specimen. Opaque white pigment visible beneath operculum on the side of the columella. Small, inconspicuous eyes. Short wide, triangular tentacles. (Figure 88). Pigmented mantle organ conspicuous, yellow, sometimes with brownish edges. Long, narrow, colourless, slightly opaque, ciliated ridge in the roof of the mantle. Spots of deep purple on the part of the body where the pigmented organ is found. Operculum: Very thin and translucent, lacking ‘ridge’ on its inner side.

Biology: Not known.

Distribution: Earlier records from Norway: three specimens and two shells from Korsfjorden and the outer part of Fanafjorden (60°12’-14’N, 150-280 m) ( Warén 1991). In my material seven specimens of which six are from the Espegrend area, mostly from the outer part of Fanafjorden, 140-220 m (close to the localities in Warén 1991). Apparently the commonest species of Liostomia in the area around Bergen. In addition to the material from Fanafjorden/Korsfjorden, two shells from around 63°10’N - 63°15’N (110-145 m, soft to sandy bottom). Finally a single specimen from Tomfjorden (66°15’N, 380- 300 m) and two shells from locations in the same general area but from somewhat shallower depths (80-160 m, mostly rather soft bottom). Outside Norway reported from western Sweden, and from the stomachs of a number of Astropecten taken near Barcelona in the western Mediterranean ( Peñas et al. 1996).

Remarks: Figure 89 shows specimens with same number of whorls of the three species of Liostomia from the southern part of Norway. L. hansgei is much longer and wider at same number of whorls than both L. afzelii and L. clavula . While the narrow, almost cylindrical L. clavula have a polished, unblemished shell surface, most specimens of L. afzelii have part of the outer layer of the shell surface eroded away. This is also the case for L. hansgei , a species where especially the protoconch is exposed to erosion. Almost 90% of specimens seen (both empty shells and live caught ones) had badly eroded protoconchs.