H. Wolda et Ds. Chandler, DIVERSITY AND SEASONALITY OF TROPICAL PSELAPHIDAE AND ANTHICIDAE (COLEOPTERA), Proceedings of the Koninklijke Nederlandse Akademie van Wetenschappen, 99(3-4), 1996, pp. 313-333
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.