Rissopsetia islandica Warén, 1989

Høisaeter, Tore, 2014, The Pyramidellidae (Gastropoda, Heterobranchia) of Norway and adjacent waters. A taxonomic review, Fauna norvegica 34, pp. 7-78 : 53-55

Rissopsetia islandica Warén, 1989

Figures 90 -91

Rissopsetia islandica sp.n. Warén 1989:24

Rissopsetia cf. islandica Warén - Høisaeter 2009

Type material: Holotype and several paratypes, SMNH 3897 and 3898.

Type locality: Skeidarardypi , off Vatnajökull, southeastern Iceland .

Material seen: Norway – Troms, upper slope, 1 shell.

Diagnosis: Shell: Almost cylindrical shell with distinctly convex whorls and deep sutures. 1.9 mm with four whorls. No visible sculpture. No visible columellar fold. Protoconch at roughly 130° and mostly submerged in first teleoconch whorl. Protoconch of same type as in Chrysallida sublustris . Soft parts: Not known. Operculum: Not known.

Biology: Not known.

Distribution: In my material a single, slightly broken, shell from Bleiksdjupet northwest of Andøya, (69°25’N, 200-700 m, stones and clay). R. islandica was described from southeastern Iceland, and reported also from western and southern Iceland in 200-570 m, and southeastern Greenland, 900 m ( Warén 1989).

Remarks: Warén (in litt 2008) confirms that, based on living material, his species is indeed a pyramidellid. My shell from the upper slope near Andøya may be of the same species,

although the illustrated types (cf. Figure 91) have strong growth lines not seen in my specimen.

Figures

Figure 90. Rissopsetia cf. islandica. A shell from Bleiksdjupet northwest of Andøya, 69°25’N, 700-200 m, 1.9 mm (Ast 5256). Figure 91. Rissopsetia islandica. Types, 2.70 and 2.77 mm long. (SEM, from Warén 1989). Figure 92. Aartsenia candida. Syntype, western Greenland (SMNH 3812) 7.0 mm. From Warén (1991). Figure 93. Eulimella laevis. (S 17-88, near Kragerø, SE of Portør 58°47’N, 09°29’E, 60 m, 4.25 mm (S 17-88). Figure 94. Eulimella laevis. Three orientations of protoconch, head-foot complex, and pigmented mantle organ. Figure 95. Eulimella ataktos. Specimen from Kobbeleia, east of Sotra, 60°17.7’N, 05°08.7’E, 70 m, 2.2 mm (ZMBN 82902). Figure 96. Top whorls of two specimens of E. ventricosa flanking one of E. ataktos, all from the same sample as the specimen in Figure 92 above (ZMBN 82902).