The aim of this work was to study communities of euglossine bees in three fragments of semideciduous forest with different sizes (8.5 ha, 86 ha and 2280 ha), in Northern Paraná State (Brazil). From November 2001 through April 2002 males of euglossine bees were sampled using chemical baits. A total of 245 males from four genera and seven species visited the baits. In the largest fragment were sampled 152 males of 6 species, in the medium, 45 males of five species and, in the smallest, 48 males of seven species. The diversity (H') and species evenness (J') varied from 1.21 to 1.42 and from 0.62 to 0.86, respectively. A change in abundance order of species was verified in the different areas. Apparently, a reduction on fragment size affected negatively the frequency of Eufriesea violacea Blanchard, the most common species (43.4%) in the largest fragment and the fourth (8.3%) in the smallest one. The results suggest the need of maintenance of large forest areas to keep viable populations of this and probably other species of euglossine bees.
Neotropical bee; orchid bee; chemical bait; semideciduous forest
