Mapping patterns of beta-diversity for Beetles across the Western Amazon Basin: a preliminary case for improving conservation strategies

ERWIN, T. L.; PIMIENTA, M. C.; MURILLO, O. & ASCHERO, V.

PROCEEDINGS OF THE CALIFORNIA ACADEMY OF SCIENCES (1907)

California Academy of Sciences

Lugar: San Francisco, California; Año: 2005 vol. 56 p. 72 - 85

0068-547X

Beetles sampled by insecticidal fogging were investigated to test for temporal andspatial β-diversity between two western Amazon rain forest sites located less thanone-degree latitude from the equator and 21 kilometers distant from each other. Arigorously controlled sampling regime of terrestrial arthropods in the canopy andunderstory resulted in a dataset containing trans-seasonal and trans-annual information.This paper focuses on the Carabidae and Curculionidae (Otidocephalini)from a larger dataset because the species accumulation curves for them nearlyreaches an asymptote, that is, enough samples have been sorted to account for nearlyall the canopy species in the general area. Canopy trees in the two sites are verydifferent at the species level (Complementarity Index = 0.73), moderately differentat the generic level (CI = 0.53), but similar at the family level (CI = 0.26). The beetlefauna was predicted to be different at the two sites depending upon feeding guildsbecause the tree species composition is so different. The assumption is made thatplant feeding species have some degree of host specialization, whereas predators andscavengers do not. For otidocephaline Curculionidae and Carabidae, this analysissuggests the opposite of that prediction: a larger percentage of herbivore species areshared between sites than predator species. These results suggest variable degrees ofspecies turnover across short distances in both forest composition and their insectdependents in the western Amazon Basin and this may impact inventory methodsand the conservation strategies derived from them.