Drosophila malerkotliana y Zaprionus indianus (Diptera, Drosophilidae) invaden poblaciones ecuatorianas de Drosophila

Abstract

The voluntary or invol· untary introduction of exotic species can cause severe impacts on ecosystem equilibrium. Rere 1 report the presence in Ecuador of Drosophila malerkotliana Parshad y Paika (t 964) and Zaprionus indianus Gupta (1970), both drosophilidea flies native to Asia. D. malerkotliana, a common invasive species, occurs in all world biogeographic regions and shows great plastícity. In February 2006, this species was reported in the "páramo" andean vegetation ofGuamanà(Páramo de la Virgen), Pichincha Province, Ecuador, at 3900-4000m.

 Z. indianus is also present in various world biogeographic regions and has invaded the Neotropics during the last few years. In January 2004, this species was captured for the first time in Pichincha Province, where it was inítially collected on the slopes of the Ilaló mountain near Quito, at 2500 m, and later in Tumbaco, Guayllabamba and Otongachi. Z. indianus has al so been collected in the provinces of Esmeraldas (Playa Ancha), Imbabura (Ibarra), Manabà(Montecristi and Jipijapa) and Ore llana (YasunÍ Scientífic Research Station). D. malerkotliana and Z. indianus are increasing their geographic range in the country: D. malerkotliana occupying unsuspected ecotypes and Z. indianus competing with native ecuadorian drosophilas. The effects these species may cause on ecosystems are unknown