Anatomical data on Solariellaobscura (Couthouy, 1838) are presented and analyzed. The main features of this species, when compared with other known trochoids, are: ctenidium with thick lamellae; enlarged ureter (that may indicate sexual dimorphism) instead of a modified urogenital papilla; odontophore very different from other trochoids such as Calliostoma, Agathistoma, Monodonta, and Gaza, with short m6, large mj and m4 pairs and absent m8 pair and posterior cartilages; esophageal valve surrounding the odontophore ventrally; anterior and mid-esophagus composed of several thin folds and a very wide cerebral ganglion. Solariellaobscura differs from Solariellavaricosa (Mighels & Adams, 1842) by having lower spire, spiral cords weaker on the base and... |