RESUMO
Tropical South America is rich in different groups of pollinators, but the biotic and abiotic factors determining the geographical distribution of their species richness are poorly understood. We analyzed the species richness of three groups of pollinators (bees and wasps, butterflies, hummingbirds) in six tropical forests in the Bolivian lowlands along a gradient of climatic seasonality and precipitation ranging from 410 mm to 6250 mm. At each site, we sampled the three pollinator groups and their food plants twice for 16 days in both the dry and rainy seasons. The richness of the pollinator groups was related to climatic factors by linear regressions. Differences in species numbers between pollinator groups were analyzed by Wilcoxon tests for matched pairs and the proportion in species numbers between pollinator groups by correlation analyses. Species richness of hummingbirds was most closely correlated to the continuous availability of food, that of bees and wasps to the number of food plant species and flowers, and that of butterflies to air temperature. Only the species number of butterflies differed significantly between seasons. We were not able to find shifts in the proportion of species numbers of the different groups of pollinators along the study gradient. Thus, we conclude that the diversity of pollinator guilds is determined by group-specific factors and that the constant proportions in species numbers of the different pollinator groups constitute a general pattern.
Assuntos
Abelhas/fisiologia , Aves/fisiologia , Borboletas/fisiologia , Clima , Pólen , Estações do Ano , Clima Tropical , AnimaisRESUMO
A new species of cloud forest butterfly, Eretris julieta n. sp. is described from a region of south-central Bolivia known as the Elbow of the Andes. It is the southernmost known representative of the genus, hitherto known only from a restricted area of interandean valleys in the department of Santa Cruz. Its affinities with other congeners are evaluated.
Assuntos
Lepidópteros/classificação , Animais , Bolívia , Feminino , Lepidópteros/anatomia & histologia , MasculinoRESUMO
A new species of cloud forest butterfly, Eretris julieta n. sp. is described from a region of south-central Bolivia known as the Elbow of the Andes. It is the southernmost known representative of the genus, hitherto known only from a restricted area of interandean valleys in the department of Santa Cruz. Its affinities with other congeners are evaluated.
Se describe una nueva especie de mariposa de bosque nublado, Eretris julieta n. sp. de la región situada en el centro-sur de Bolivia, conocida como el Codo de los Andes. Esta especie es la más sureña de todo el género y es conocida hasta la fecha unicamente de una área restringida de valles interandinos en el departamento de Santa Cruz. Se evaluan sus afinidades con otras especies del género Eretris.