New Charopidae from Chile and Argentina, Stephacharopa calderaensis n. gen. and n. sp. (Mollusca: Gastropoda, Pulmonata), with remarks on the taxonomy of genus Stephadiscus.

MIQUEL, S.E.; ARAYA, J.F.

ARCHIV FUR MOLLUSKENKUNDE DER SENCKENBERGISCHEN NATURFORSCHENDEN GESELLSCHAFT

E SCHWEIZERBARTSCHE VERLAGS

Lugar: Stuttgart; Año: 2013 vol. 142 p. 245 - 256

0003-9284

A new genus and new species of Charopidae Stephacharopa calderaensis is described from Chile and Argentina. The new genus is diagnosed by the following characteristics: shell with rib ornamentation of different morphology between protoconch and teleoconch, where the number of embryonic ribs is under a hundred. Its type species S. calderaensis is characterized by having an orbicular shell, of typical size for the family, protoconch with 40-60 radial ribs, teleoconch with sculpture of ribs and nodulose ribs, last whorl with around 90-95 such ribs, umbilicus perspective and well-developed. This new genus includes also Stephacharopa testalba (HYLTON SCOTT 1970) n. comb. and Stephacharopa  distincta (HYLTON SCOTT 1970) n. comb. Stephacharopa is recorded, principally, from central and northern Chile. Genus Stephadiscus is defined by the following: protoconch and teleoconch with similar ornamentation, thin and nodulose ribs, separation between protoconch and teleoconch faintly marked by a tenuous scar or callus, and over a hundred of embryonic ribs . Species included in genus Stephadiscus are S. lyratus, S. rigophila, S. perversus, S. rumbolli and S. stuardoi, with distribution in southern South America.