Paulista Bumble Bee

B. pauloensis are predominantly black in color. The thorax of the bee is completely black while the abdomen is black with a small amount of paler hair towards the apex. B. pauloensis have a long tongue that facilitates the process of retrieving nectar from flowers with deep corollas. The antennae of B. pauloensis are also relatively long. Workers have a wing length that ranges between 4 and 10 mm. Queens are usually two to three times the mass of workers.

B. pauloensis nests are usually found above the ground. Nests have been found in an array of different locations, including warm, tropical areas and cold, high altitude environments. Such a diverse geographic distribution illustrates how B. pauloensis has the ability to adapt to a wide range of conditions and pollen sources. Although most nests are built on the ground, nests have been found elevated in trees above the ground. Research indicates that climate dictates whether a particular nest will oscillate between polygynous and monogynous cycles. B. pauloensis are found throughout South America, including Colombia, Ecuador, Brazil, and Argentina.

Agonistic behaviors have been recorded between B. pauloensis queens in colonies that are in polygynous phases. These interactions are mainly a result of queens establishing and maintaining specific territories within the brood clump. In such environments, queens guard their brood clump territories by lunging at other queens that may intrude into their territory. Conflicts between queens in such environments can lead to the death and expulsion of rival queens by the dominant queen. After all of the other queens are expelled, the dominant queen will take over the colony and initiate the monogynous phase of the colony life cycle. Relative levels of queen aggression and dominance correlate with a number of physical indicators including, ovary size, age.