Scaptotrigona postica

Scaptotrigona postica (also known locally in Brazil as mandaguari) is a species of stingless bee that lives mainly in Brazil. It is a eusocial bee in the tribe Meliponini. S. postica is one of 25 species in the genus Scaptotrigona and is a critical pollinator of the tropical rain forests of Brazil. They construct their nests in hollowed sections of tree trunks, allowing for effective guarding at the nest entrance. This species shows colony structure similar to most members of the Meliponini tribe with three roles within the colony: queen, worker, and male. S. postica individuals have different forms of communication from cuticular hydrocarbons to pheromones and scent trails. Communication is especially useful during worker foraging for nectar and pollen through the Brazilian tropical rain forests. S. postica is a very important pollinator of the Brazilian tropical rain forests and is widely appreciated for its honey. Stingless bees account for approximately 30% of all pollination of the Brazilian Caatinga and Pantanal ecosystems and up to 90% of the pollination for many species of the Brazilian Atlantic Forest and the Amazon. Scaptotrigona postica is one of the 25 species in the genus Scaptotrigona, a eusocial genus of bees. It was first described by Pierre André Latreille in 1807. In the past, it has also been called Melipona postica, Trigona postica and Trigona rustica. This bee is a member of many taxonomic sub groups including the subclass pterygota (winged insects), suborder apocrita, and subfamily Apinae (stingless bees). These groups of bees are winged, have a social hierarchy, and do not have defensive stingers. Instead they bite and try to enter in body orifices as nose and ears. This species can be very aggressive against humans that approach its nest. Other similar species in this genus include Scaptotrigona hellwegeri, Scaptotrigona mexicans and Scaptotrigona pectoralis. Scaptotrigona postica are medium-sized, averaging 1.2 cm in length and cross-sectional area of 5.3 mm2. They appear dark gray with some sections of dark yellow in color, with black eyes. Queens are the largest bees in the nest, averaging 38–50 mg, and are identifiable by their swollen abdomens. Also, they have more of the yellow coloring than the workers and drones. There is one queen per colony, but once virgin queens are born, they are tolerated for 15 days on average until they either leave the colony or are killed. S. postica queens cannot independently colonize, instead needing a group of workers to help build a new colony. While virgin queen bees must leave the colony, a queen holds her position for several years Workers are the smallest bees in the nest, weighing between 15–22 mg and are black in color. They assume different roles in the nest based on their age. Drones are almost identical in size as the workers, but weigh slightly more. They weigh on average 17–30 mg and are black in color. The drones are the male bees hatched from unfertilized eggs. Their role is to mate with the queen to produce female bees. They do not participate in many other activities. Scaptotrigona postica nest in partially hollow sections of trees in the tropical rain forests of Brazil. The nests range from 3–7 meters above ground with a canopy overhead, approximately 15–20 meters above the nest. One of the common trees nested by S. postica is the Caryocar brasiliense, also known as the cerrado-tree. The nest consists of inner brood cells and a short entrance tube. The brood cells are sometimes compacted into combs and large wax pots for storage of honey/pollen. The cells are composed of cerumen, are vertical in shape, and open at the top of the cell. The entrance to the nest has an average cross-sectional area of 143.5 mm2 and is guarded by about 8 guards. These bees stand at attention near the entrance, occasionally flying back and forth in front of the entrance.