Carabid beetle diversity and community composition as related to altitude and seasonality in Andean forests

Abstract

Carabid beetle (Coleoptera: Carabidae) diversity and community composition was investigated along an altitudinal gradient from 1400 m to 3400 m in southeastern Peru, utilizing recently published data of the first systematic inventory of carabid beetles in the region. The study transect is located in one of the highest biological diversity regions in the world. Active and passive collection techniques were used to examine temporal (rainy and dry seasons) and spatial (altitude) structure of adult carabid beetle assemblages. After adjusting for collection effort, species richness, as estimated by the Mao Tau richness estimator, peaked at 2000 m, some 600 meters above the lowest sampled altitude in this study. Similarity between species assemblages from different altitudinal sites was ≤52%. Species richness was approximately 10% higher in the rainy season than the dry season, with 64% of species occurring in both seasons. Despite the importance of multi-seasonal survey sampling for Neotropical habitats, most surveys to date have been limited to the dry season. Studies of organisms that can serve as indicators of habitat shift along altitudinal gradients become increasingly relevant with predicted global climate change.