Architectonicidae en la Formación Navidad, Mioceno, Chile Central. Parte II. Architectonica (Architectonica) nobilis karsteni Rutsch, 1934. (Mollusca: Gastropoda)

Abstract

A well preserved specimen of Architectonica (Architectonica) nobilis karsteni Rutsch, 1934 collected a t Navidad Formation is here studied. The sample was found in an isolated boulder a t the base of the coastal cliff, near Punta Perro, Central Chile (33° 54' S). This finding becomes the most southern record known in the dispersal of A. (A) nobilis group, wich has a chronostratigraphic distribution ranging from Lower Miocene to Recent in the present Panamic and Caribean marine provinces. This fact would indicate that the containing beds in Navidad Formation (Navidad Member) would not be older than Lower Miocene. The presence of this subspecies in the mentioned sedimentary deposits is here suggested as a temporal tropical-faunal migrant from the north.