Dragonfly diversity of the Argentinean Chaco

VON ELLENRIEDER

Xalapa, Mexico

Congreso; 6th WDA International Congress of Odonatology; 2009

Instituto de Ecologia, UNAM y WDA

Odonates of temporary pools, permanent ponds, and rivers were sampled in the Chaco biome of NW Argentina. Presence/absence information of species from samples and from examination of collections and literature was recorded in a spatial-relational database. Alpha, beta, and gamma diversity and total species richness expected for the area were estimated. Similarity in composition of Chaco odonate assemblages was analyzed using multivariate cluster analysis. Odonate composition of the Chaco was compared with that of neighboring Yungas and Paranense biomes. Information from 95 localities yielded 88 species, from which five are new records for the country and 31 are new records for four provinces. Species composition was found to be related to both longitudinal sector and type of environment, with eastern assemblages mostly segregated from western ones, and assemblages from large permanent lentic water bodies (oxbow lakes and dams) segregated from those of rivers. Percent complementarity values show Chaco odonate composition to be slightly more dissimilar to that of the Paranense than to the Yungas adjacent areas. Odonate species found in the Chaco are more widely distributed in the Neotropical region, with only three potential endemisms.