Five new dry-area South American Strymon species (Lycaenidae: Theclinae) and their biogeographic significance

Abstract

Five hairstreak species (Eumaeini) are described that occur in dry areas of South America. They are Strymon ahrenholzi Nicolay & Robbins, Strymon jacqueline Nicolay & Robbins, Strymon giffordi Nicolay & Robbins, Strymon michelle Nicolay & Robbins, and Strymon lamasi Nicolay & Robbins. Three inhabit the Atacama/Tumbesian/Río Marañón areas of southwestern Ecuador and northwestern Peru, one the upper Río Apurímac in south-central Peru, and one the central plateau of Brazil. Evidence is presented concerning the closest relatives of each new taxon. The taxonomy of Strymon, which now contains 54 described species, is reviewed. To assess the biogeographic significance of the new taxa, the Strymon species with restricted distributions in various South American xeric regions are listed. The Atacama/Tumbesian/Río Marañón area is currently the richest for Strymon endemics. The closest relatives of the Strymon species in the Atacama/ Tumbesian/Río Marañón region occur in variety of other biogeographic areas, suggesting a lack of diversification within this region. This pattern is similar to that of bird distributions, but not to those of lizards and amphibians.