Resumen

BONILLA-RIVERO, Ana; LOPEZ-ROJAS, Héctor  y  MACHADO-ALLISON, Antonio. Especiación vicariante en el género gephyrocharax eigenmann 1912 pisces: characidae: glandulocaudinae de venezuela. INCI [online]. 2002, vol.27, n.3, pp.118-127. ISSN 0378-1844.

To obtain preliminary information on the biogeography of Gephyrocharax species, the morphologic and genetic patterns of its Venezuelan representatives were identified. Evidence from vicariant events associated with the eastwardly progression of the Orinoco River to its present position and the Andes uplifting, the species’ actual distribution patterns, and the unique morphologic and genetic patterns of G. melanocheir, which differentiate it from the other two species, allow us to hypothesize that the current distribution of the three species was produced by the isolation of small populations in Colombia and northeastern Venezuela (present G. melanocheir), followed by the separation of the present G. venezuelae in central-western Venezuela. Most of the ancestral population remained in the main channel of the Orinoco River (present G. valencia).

Palabras clave : Especiación ; Morfología Cuantitativa ; Isoenzimas ; Biogeografía ; Pisces .