Diversity and biogeographic affinities of Apionidae (Coleoptera: Curculionoidea) along an altitudinal gradient in El Cielo Biosphere Reserve of northeastern Mexico

Resumen

The altitudinal and temporal distributions of species in the family Apionidae (Coleoptera: Curculionoidea)
were studied in El Cielo Biosphere Reserve (ECBR) in the state of Tamaulipas, northeastern Mexico. Species richness,
diversity and abundance were recorded along an altitudinal gradient, from 100 to 1 900 m. A total of 571 individuals of
51 species were collected, representing 30% of the total species of Apionidae recorded for Mexico. Richness estimators
(Chao 2) indicated that 75% of the species present were sampled. Species richness and diversity was greatest in tropical
forests. Species geographic distributions were found to fall into 3 categories: mega-Mexico, tropical and temperate. The
majority of the species (55.3%) were restricted to mega-Mexico (southern southwestern US to northern Nicaragua),
with fewer species with tropical (27.7%) and temperate (17.0%) distributions. Species with tropical distributions had
highest diversity and greater overall abundance in low elevations in tropical forests when compared to higher elevation
forests (cloud and pine/oak). In contrast, diversity and abundance for species with temperate and mega-Mexican
distributions were similar in all forest types. Greater richness and abundance occurred during the dry season (December
through May) than the rainy season, suggesting populations of Apionidae were in immature stages during this latter
period, with active adults predominating during the dry season, many of which were probably in a non-reproductive
physiological state.