Abelhas euglossina das serras do norte do estado do Amazonas

Abstract

Nineteen hundred and fifty-nine orchid bees have been collected in three distinct mountain ranges in the border between the Amazonas state of Brazil and Venezuela, in the mid/upper Negro basin. Two new species have been found, and the geographic distribution of other species has been increased. The community of each mountain range has been analyzed; the effects of altitude, area of different altitudinal intervals and mountain system on species richness and composition have been tested, as well as the so-called mid-domain effect (MDE). Area and altitude have not affected species richness in any of the mountain systems studied. The species composition in each point was converted to two NMS ordination axes, which explained 79% of data variation. The position of sampling sites relative to those axes could be explained by altitude. The MDE has not explained the species richness in any of the three mountain ranges. The species assemblage has been compared with that of other studies in the amazonic basin, and showed a distinct composition.