First record of buccinid genus Chauvetia

Until now, the buccinid genus Chauvetia was considered of European or West African origin, and is still endemic to these areas today. This paper describes the oldest representative of the genus, Chauvetia inopinata nov. sp., from the upper Burdigalian-lower Langhian transition Cantaure Formation of Venezuela. This surprising record suggests a New World tropical origin to the genus and subsequent immigration to the Old World before the earliest known Old World record, which is upper Tortonian. We postulate that this pre-late Tortonian (pre-8.12-7.42 Ma) dispersal of the tropical Gatunian west-Atlantic Chauvetia into the tropical East Atlantic European-West African Province most probably happened during the 10.71-9.36 Ma interval (early-mid Tortonian) during which the Circum-Tropical Current weakened, and the northward Intra-Caribbean Current had started, enhancing the Gulf Stream and the North Atlantic Current. This new data constitutes compelling evidence of a pre-Pliocene eastward dispersal of New World shallow marine organisms across the Atlantic

A new species of Leptochiton (Polyplacophora: Leptochitonidae) from the Southwestern Atlantic

Leptochiton sanmatiensis, new species, is described from shallow-waters of northern Argentina. The species is characterized by having a quincuncial arrangement of tegmental granules on head valve, lateral areas of intermediate valves and postmucronal area of tail valve, and a longitudinal arrangement of these structures on the central areas of intermediate valves; each granule having a macraesthete and four micraesthetes. In addition, the new species has pectinated dorsal scales, with 14-21 ridges; a low number of ctenidia (up to six on each side in the largest specimens); and the second lateral tooth with three denticles in the cusp. The species lives on small gravel and shells.Fil: Güller, Marina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales ; ArgentinaFil: Liuzzi, Maria Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales ; ArgentinaFil: Zelaya, Diego Gabriel. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin