The freshwater centropagid Osphranticum labronectum Forbes, 1882 (Crustacea: Copepoda: Calanoida) in Mexico with description of a new subspecies

Disponible para usuarios de ECOSUR con su clave de acceso

From a zooplankton survey carried out during January 1998 in several ponds of the Mexican state of Tabasco, southern Gulf of Mexico, several specimens of the freshwater centropagid copepod Osphranticum labronectum Forbes, 1882 were collected. This is a widespread species in North America. There is a single record south of 25°N, in Guatemala (ca. 15°N). The species has not been reported from the large area lying between these records, mostly represented by Mexico. This finding in southeast Mexico is helpful to understand the distributional range of the species. It is also the first record of a freshwater species of the Centropagidae for Mexico. The Mexican specimens show morphological differences when compared with previously described material, mainly on the armature of male and female fifth legs, and in their size. These differences, and the assumed isolation of the Mexican populations from the species main distribution area in the Nearctic region, suggest that the Mexican population is a new subspecies, O. labronectum mexicanum. Taxonomic illustrations, including structures not depicted or described before for the species, are also provided herein. eng