Diversification patterns in Melanoplinae (Orthoptera: Acrididae) grasshoppers from the Andes highlands

CIGLIANO M.M.; POCCO M.E.; LANGE C.E.

Kunming

Congreso; 11th International Congress of Orthopterology; 2013

The Orthopterists' Society

Members of the Melanoplinae subfamily usually dominate both in species and individuals in most temperate grasshopper communities of the Americas and are one of the main components of Acrididae fauna in the high Andes of South America. The Andes are characterized by a long list of outstanding features including numerous endemic organisms with interesting life histories. Despite their young age, the tropical Andes are highly diverse due to recent geological uplift. Different scenarios including habitat diversity resulting from differences in orogeny, topography, soils, climate and elevation have been proposed to explain the diversification of high Andean taxa. Species have spread North and South along this mountain chain, and also up and down in elevation during colder times through repeated glaciations. The Andes provide altitudinal zoned habitats from rainforest to Paramo to glaciated peaks, an East?West differentiation into wetter and drier slopes through rain shadow effects. So far, there is no comprehensive study of melanopline fauna of the Andes, and there are only few records of highland species of the Peruvian and Bolivian Andes. Recent surveys that resulted in the discovery of several new melanopline taxa illustrate discrepancies between perceived and actual species diversity. Cladistics-biogeographic analyses on Melanoplinae taxa were conducted to test the different scenarios proposed to explain diversification patterns of distinct possible geographic modes of speciation in montane habitats of Bolivia and Peru.