Helix ruderata var. viridana Roffiaen 1868

Helix ruderata var. viridana Roffiaen, 1868 Helix ruderata var. viridana Roffiaen, 1868: 68. Type material. Not located. Type locality. Switzerland: Handeck (Handegg). “ La Handeck ” (Roffiaen 1868: 68). Taxonomic status. Junior synonym of Discus ruderatus (Hartmann, 1821). Discussion. This variety was described to allocate specimens for which the single conchological character noted by Roffiaen (1868) was the “ pale greenish colour ”. The shell of Discus ruderatus is known to typically to be light brown to reddish brown (Welter-Schultes 2012), though paler yellowish and greenish brown specimens are also common (Kerney et al. 1979; Wiese 2014). Furthermore, the type locality of this variety is within the known distribution of D. ruderatus in Switzerland (Turner et al. 1998), and Roffiaen (1868) himself mentioned “ typical ” D. ruderatus occurring in the same place. Thus, even without access to type material, it can be surmised that Helix ruderata viridana is very likely a junior synonym of D. ruderatus.