Abstract

A new species of Crepidula is described. It was collected together with Pagurus edwardsii Dana and Pagurus perlatus H. Milne Edwards, inhabiting the inside of empty shells of Tegula euryomphala Jones and other gastropods. The shell is low convex-oval in juveniles, low convex-oblong in males and concave-oblong elongated in females. In the adult phases the apex projects slightly al the posterior border. The sinusoidal septum is 'V' shaped at its centre, with a smooth sulcus in the left quarter. The osphradium has 2-13 digitiform leaflets according to phases of the life cycle. The characteristically thin, external-lateral teeth of the taenioglossate radula possess a row of denticles. In addition, evidence is given that: (1) males have a lanceolate penis with a spermatic tube; (2) the intracapsular-embryonic development starting with many embryos, occurs with a decrease at the larvae-protoconch stage, each one with an adhered-vitelline mass, and culminates with a few prehatching juveniles of 1 mm size. In the expression of the consecutive-protandric hermaphroditic sexuality, the male phase is truly separated from the female phase by a transition period at the population level. The shell and radular morphology, intracapsular development and ecological antecedents allow the proposal of Crepidula coquimbensis as a new species, and suggest a future taxonomic revision of the group based, moreover, on osphradium structure and new characters of the reproductive system, such as penis morphology.