Helix arbustorum var. trochoidalis Roffiaen, 1868

Helix arbustorum var. trochoidalis Roffiaen, 1868

Fig. 4 B View Figure 4

Helix arbustorum var. trochoidalis Roffiaen, 1868: 69, pl. 1, fig. 2.

Type material.

RBINS I.G.9154 / MT.4172 and I.G.9154 / MT.4171 : respectively, 7 and 6 possible syntypes, ex de Cort coll.

Type locality.

Switzerland: Andeer .

Taxonomic status.

Junior synonym of Arianta arbustorum (Linnaeus, 1758) .

Discussion.

The two available specimen lots were collected at the type locality Andeer and stem from the collection of Hugo de Cort. There is no indication that they came from Roffiaen’s collection, but the specimens are a good conchological match to Roffiaen’s brief description and figures ( Roffiaen 1868: pl. 1, fig. 2 a, b). Thus, we interpret the present specimens as possible syntypes.

This variety was described to denote specimens with an elongated spire, which gives the shell a more trochoid shape. As mentioned above for shell colouration, intraspecific variation in shell shape (including spire height) is common across members of A. arbustorum (e. g., Germain 1930; Baminger 1997). Thus, Helix arbustorum trochoidalis is here considered synonymous with A. arbustorum .