Parthenina sarsi ( Nordsieck, 1972 )

Høisaeter, Tore, 2014, The Pyramidellidae (Gastropoda, Heterobranchia) of Norway and adjacent waters. A taxonomic review, Fauna norvegica 34, pp. 7-78 : 18

Parthenina sarsi ( Nordsieck, 1972)

Figure 12

Chrysallida (Besla) sarsi n. sp. - Nordsieck 1972:98 Chrysallida sarsi Nordsieck - Fasseaux 1974 ; Warén 1991; van der Linden & Eikenboom 1992; Høisaeter 2009

Chrysallida (Besla) sarsi Nordsieck - Smith & Heppell 1991 ; van Aartsen & Menkhorst 1996

Parthenina sarsii (Nordsieck) - Schander et al. 2003

Type material: Two syntypes, SMNH 4110 .

Type locality: Charleroi , Belgium (fide Warén 1991) .

Material seen: None.

Diagnosis: Shell: According to Warén (1991), it is most reliably distinguished from P. indistincta in being proportionally wider and having 13 axial ribs visible rather than 10-11 visible ribs in P. indistincta . At least six, usually eight or more spiral cords on lower part of body whorl. Soft parts: Not known.

Operculum: Not known.

Biology: Not known.

Distribution: Its presence in Norway is based on two shells from the Bergen area mentioned in Warén (1991). Outside Norway he reports 12 specimens from the Koster area in western Sweden. Otherwise it is known from the Atlantic coasts of Europe south to NW Spain ( Warén 1991).

Remarks: The species is included here on the authority of Warén (1991). The species was named and described by Nordsieck (1972) based on shells donated by Fasseaux, from La Panne and Colunga, Belgium. A more detailed description and several photographs are given in Fasseaux (1974). The taxon is pictured in van Aartsen (1977), who also regards it as a good species, and says it is found along the Atlantic coast of Europe. In the opinion of Nordsieck (1972) the form was originally described by G.O. Sars (1878) as Parthenia interstincta var. The justification for this identification seems flimsy, and I agree with Warén (1991) that the specimens pictured and described by G.O. Sars are not conspecific with the specimens described and depicted in Fasseaux (1974) and van Aartsen (1977). The specific name is still valid though, even if Nordsieck’s identification of G.O. Sars’ figure should be due to a misidentification. If the specimens from the Bergen area are indeed correctly identified, this is an extremely rare species in our fauna. I have not seen any shells among my roughly 35 000 pyramidellid shells. All shells of ‘ C. decussata ’ reported from the coast of the Netherlands belong to this species (de Bruyne & al. 2013).