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.

We investigated whether Lepidoptera species richness in the tropical Andes is distributed evenly across the latitudinal gradient, explored the spatial correlations between different taxonomic groups, and investigated historical and ecological factors responsible for shaping the observed patterns. We interpolated species richness from collecting records of nine ecologically diverse taxa of montane Lepidoptera, eight of butterflies (Ithomiini, Acraeini, Callicorini, Pronophilina, Aporiina, Leptophobia, Penaincisalia, and Forsterinaria) and one of moths (Geometridae: Erateina) along elevational transects from 1000 to 3500 m every two degrees in latitude between 11°N and 27°S. We used multiple regression to assess the role of climatic and historical variables in shaping their species richness patterns, and Spearman's correlation coefficient to examine the correlation of species richness gradients between pairs of taxa. We found that Lepidoptera species richness in the tropical Andes is distributed unevenly across the latitudinal gradient, differing considerably between the least and the most diverse transects, with a peak at 3–11°S, and is strongly correlated among all nine taxa. Geological age of the Andes, area and climatic seasonality explained the most variation in species richness, with age dominating in the north and seasonality in the south. The latitudinal gradient in east Andean Lepidoptera species richness is likely a result of historical and contemporary factors, in particular temperature seasonality and the greater age of the Andes south of the Equator. Local aspects of species richness patterns are due to small‐scale geological or climatic phenomena, for example, the peak at 3–5°S which results from local mixing of east‐west Andean faunas in the Huancabamba Deflection area.

Una Nueva Especie de Eretris Thieme (Lepidoptera: Nymphalidae, Satyrinae) de la Región del Codo de Los Andes en Bolivia RESUMEN -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 afi nidades con otras especies del género Eretris. PALABRAS-CLAVE: Eretris subpunctata, ocelos, Pronophilina, Yungas, taxonomíaABSTRACT -A new species of cloud forest butterfl y, 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 affi nities with other congeners are evaluated.

The geographical distribution of Morpho helenor (Cramer) in Bolivia is mapped from the study of specimens preserved in Bolivian and foreign collections, and from recent field studies in various ecoregions. One subspecies, M. h. theodorus Fruhstorfer, inhabits Amazonian moist forests in the western and northern parts of the country. Another subspecies, M. h. coelestis Butler, is common in moist cloud forests (Bolivian Yungas), but also occurs to the North and North-East. We describe a new subspecies, M. h. prometa ssp. nov., from Southern Andean Yungas. Transition zones between theodorus and coelestis are highlighted, where specimens exhibiting intermediate phenotypes were collected. The pattern of geographic transition from M. h. coelestis to M. h. prometa needs to be documented. M. h. prometa inhabits sub-humid, semideciduous forests, whereas M. h. theodorus and M. h. coelestis live in rainforests. M. h. coelestis populations are found from less than 100 m to more than 1600 m a.s.l.; M. h. theodorus has been collected at more than 1000 m a.s.l.; and M. h. prometa between 500 m and 1400 m a.s.l.. Therefore, Bolivian M. helenor populations are distributed throughout a wide range of ecological contexts: we discuss the habitat plasticity of the species in light of available knowledge of its geographical distribution and habitats in the Neotropical Region.

Eryphanis zolvizora (Hewitson, 1877) is a rare Andean endemic butterfly, described from Bolivia, which has been historically classified either as a unique species, or as part of a group of three allopatric species from Bolivia, Ecuador and Colombia. In this paper, the group is revised using more than 200 specimens housed in 34 European, and North and South American public and private collections. For the first time, the presence of the group in Western Ecuador and Venezuela is confirmed, and important data on Peruvian populations are provided. In some populations, individual variations of genitalia are observed. Nevertheless, male genitalia allow the distinction of four geographical groups. Considering also habitus characters, eight taxa are distinguished and considered to be subspecies, of which five are new: Eryphanis zolvizora inca ssp. nov., Eryphanis zolvizora chachapoya ssp. nov., Eryphanis zolvizora casagrande ssp. nov.., Eryphanis zolvizora reyi ssp. nov., and Eryphanis zolvizora isabelae ssp. nov.  In the present state of knowledge, these taxa are allopatric, except for a possible geographic overlap in central Peru, where data are insufficient to prove sympatry. The “several subspecies vs. several species” dilemma is discussed, considering its impact for conservation action and policies.

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