Altitudinal distribution, diversity and endemicity of Carabidae (Coleoptera) in the páramos of Ecuadorian Andes

Pierre Moret (1)

1 TRACES - Travaux et recherches archéologiques sur les cultures, les espaces et les sociétés

Species richness and diversity of Carabidae (Coleoptera), as well as rates of endemicity, are studied along altitudinal transects in the páramo of Ecuadorian Andes, from 3500 to 5000 m. Whereas a global tendency to reduction of species richness is evident from 4200 m upwards, two zones of high diversity and high proportion of endemic species occur at 3800-4000 m and at 4200-4400 m. Species turnover between grass páramo and superpáramo is signifi cantly higher in drier mountains, especially in the Western Cordillera, than in humid mountains of the Eastern Cordillera. The altitudinal range of Carabid species tends globally to decrease along the vertical gradient, but with important local variations due to microenvironmental factors, especially humidity rate. When compared with recent phytogeographical studies, these results tend to support the idea that the majority of tussockgrass páramo is a secondary anthropogenic ecosystem. On the contrary, it is argued that the xeric landscape of the Chimborazo "arenal" is primordial, based on the presence of a stenotopic and possibly relict species, Pelmatellus andium Bates 1891.

Mots clés: Coleoptera; Carabidae; biodiversity; altitudinal distribution; Andes; páramo; Ecuador

Domaines: Biodiversité; Biodiversité et Ecologie

Pierre Moret. Altitudinal distribution, diversity and endemicity of Carabidae (Coleoptera) in the páramos of Ecuadorian Andes. Annales de la Société Entomologique de France, 2009, 45 (4), p. 500-510. ⟨hal-00723855⟩