Spixia pyriformis

Oroño, Eugenia Salas, 2007, Taxonomic review of the Spixia pyriformis species complex (Gastropoda: Pulmonata: Odontostominae), Zootaxa 1498, pp. 1-25 : 4

Spixia pyriformis species group:

Diagnosis: Pyriform to subpyriform shell shape. Aperture corresponds to 1/3 of total shell length in the S. pyriformis group. If shell shape is pyriform diameter of first three whorls changes abruptly towards body whorl. First three whorls turret shaped, last two whorls convex of abrupt growth. Spiral angle from 40° to 65°. Maximum angle from 105° to 135°. If shell shape is subpyriform diameter of first whorl changes smoothly and uniformly towards the body whorl. First five whorls convex, of continuous growth, rest of the whorls less convex. Spiral angle from 30° to 42°. Maximum angle from 125° to 140°. Pallial system with conspicuous pallial gland at distal portion of pulmonary roof. Penis with internal penial gland. Penis inner wall with five areas (I to V) clearly defined through different sculptural pattern. Vas deferens sticked to retractor muscle at penial proximal area (I) or constriction and widening area (II).