A remarkable new genus and species of subterranean freshwater snail from a recently dried-up spring of Viesca, Coahuila, Northern Mexico Author Czaja 1, Alexander Facultad de Ciencias Biologicas, Universidad Juarez del Estado de Durango, Av. Universidad s / n, Fraccionamiento Filadelfia, 35010 Gomez Palacio, Durango, Mexico Author Gladstone 2, Nicholas S. Facultad de Ciencias Biologicas, Universidad Juarez del Estado de Durango, Av. Universidad s / n, Fraccionamiento Filadelfia, 35010 Gomez Palacio, Durango, Mexico Author Becerra-Lopez 1, Jorge Luis Facultad de Ciencias Biologicas, Universidad Juarez del Estado de Durango, Av. Universidad s / n, Fraccionamiento Filadelfia, 35010 Gomez Palacio, Durango, Mexico Author Estrada-Rodriguez 1, Jose Luis Facultad de Ciencias Biologicas, Universidad Juarez del Estado de Durango, Av. Universidad s / n, Fraccionamiento Filadelfia, 35010 Gomez Palacio, Durango, Mexico Author SaenzMata 1, Jorge Facultad de Ciencias Biologicas, Universidad Juarez del Estado de Durango, Av. Universidad s / n, Fraccionamiento Filadelfia, 35010 Gomez Palacio, Durango, Mexico Author Hernandez-Teran 3, Fernando Facultad de Ciencias Biologicas, Universidad Juarez del Estado de Durango, Av. Universidad s / n, Fraccionamiento Filadelfia, 35010 Gomez Palacio, Durango, Mexico text Subterranean Biology 2021 2021-08-05 39 129 141 http://dx.doi.org/10.3897/subtbiol.39.67799 journal article http://dx.doi.org/10.3897/subtbiol.39.67799 1314-2615-39-129 7C135129340D49D48BBDDD8C9AD3C358 949FA919D03D5786B2FC5FD157ECCCD3 Phreatoviesca Czaja & Gladstone gen. nov. Type species. Phreatoviesca spinosa by present designation. Diagnosis. Shell small, conical in form, protoconch sculptured with coarsely honeycomb-like pits, teleoconch with curved ribs which are at the carina modified into regularly spaced shovel-shaped spines (Figs 14 , 24 ), body whorl always open-coiled, some specimens with a corkscrew morphology, apertures large, ovate, rarely rounded, often trumpet-like. Differential diagnosis. The characteristic combination of three aforementioned shell features (open coiling of the last whorl, shovel-shaped spines, and protoconch with coarsely honeycomb-like pits) separate the new genus clearly from shells of all other subterranean (and epigean) genera. Some members of Phreatodrobia Hershler & Longley 1986 and Paludiscala Taylor 1966, genera which include exclusively subterranean species, also have conical shells, but these are not uncoiled (except the slightly uncoiled Phreatodrobia nugax (Pilsbry & Ferriss, 1906) to this extent do not possess prominent spine ornamentations. Etymology. The name is derived from Greek phreato = groundwater environment, and Viesca (referring to the town of Viesca where the shells were found).