Oxychilus (Drouetia) viridescens (Gastropoda: Pulmonata: Oxychilidae), a new species from Santa Maria, Açores, and a review of the subgenus Author De Frias Martins, António M. Author Brito, Carlos P. Author Backeljau, Thierry text Zootaxa 2013 3619 3 343 368 journal article http://dx.doi.org/10.11646/zootaxa.3619.3.5 1557e4fb-c16a-447b-a152-f4a08a8739b8 1175-5326 217371 4FB7A97C-D25F-41C8-8C62-2664E6E6F148 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 ).