DIVERSITY AND SEASONALITY OF TROPICAL PSELAPHIDAE AND ANTHICIDAE (COLEOPTERA)

Diversity and seasonal abundance patterns in anthicid and pselaphid be etles were studied at six sites in the Republic of Panama by means of light-traps. Pselaphids were much richer in species than anthicids, an d the latter were rare or absent at higher elevations. Many more speci es of pselaphids were found in these tropical samples than in any temp erate zone samples known to us. Between-site similarities in species c omposition were generally low, much lower than between-year within-sit e similarities, but were highly correlated with such similarities calc ulated for other groups of insects from these same sites. Seasonal var iation in abundance was characterized using circular statistics. The d egree of seasonality, measured by the 'Mean Vector', was higher at the seasonal than at the less seasonal sites, but much lower than at most temperate zone sites. At two of the three sites where anthicids were relatively common, they had the mean of their seasonal distribution ma inly at the late dry season and early rainy season, while the means of the pselaphids were found throughout the rainy season. At the third s ite, an aseasonal one, means of abundance of species of both families were found throughout the year. At two sites, but not at the other sit es, many species had a distinct bimodal distribution. The between-site variation in seasonality was of the same order of magnitude as the wi thin-site between-year variation.