Subgenus Drouetia Gude, 1911

Original description. Shell hyaline, very finely striated, and covered with excessively fine spirals, imperforate, the reflexed columella slightly twisted.

Type species. Helix atlantica, Morelet & Drouët, 1857, from the Azores [São Miguel Island (Riedel 1964)].

Remarks. Gude (1911) proposed Drouetia as a monotypic genus for the endemic Helix atlantica, which according to Morelet (1860) occurred in most islands of the Azores. Zilch (1959) relegated the name to subgeneric status, and since then it has been generally accepted in this category. After Riedel’s (1964) anatomical research, several new species of Drouetia have been recognized (Martins 1981, 1989) and the group was recorded in all Azorean islands (Martins et al. 1989, 1990).