Angiopolybia pallens is a species of social wasp predominantly found in South America. The wasp is generally seen in Brazilian rainforests. This species was discovered by Lepeletier in 1836. It typically feeds on nectar and carrion. In fact much of its feeding behavior and impact on humans is centered on feeding on animal carcasses. The wasp species displays a caste differentiation that can be seen by difference in ovarian development. Additionally they have a unique colony establishment procedure. It begins with a few individuals from the nest leaving to find a good site and then the rest of the colony follows using specific communication signals that are further discussed in this article.
Taxonomy and phylogeny
The tropical social wasp genus Angiopolybia contains four different species. The wasp is within the tribe Epiponini and is a basal swarm-founding wasp. A swarm founding wasp is a wasp that finds its nest by sending out a group of wasps going out to find a new nest site. It is considered a eusocial wasp. Most social wasps have the unique characteristics of a caste system in which the queen wasp is the primary producer of offspring. This characteristic of a caste system is evident in the behavior of A. pallens. Lepeletier originally discovered the species in 1836. He classified the wasps under a different genus Rhopalidia and when he discovered the wasps he also found another species under the name of R. rufithorax. The species was later transferred to the genus Angiopolybia that shared with A. paranesis, A. obidensis, and A. zischkai. These species are widespread in the Amazon and extend from Costa Rica to Bolivia.
Description and identification
Angiopolybia pallens are distinguished by the ombre-like progression from yellow to black on their bodies. They have four legs that progress from a lighter yellow to a dark orange. The wasp's body is skinny with the back coming to a point. Their wings are slim and black. The slim wings cause A. pallens to fly low and for short distances. This means that their foraging area is limited to about 1,800 square meters. The workers, queens and intermediates of the colony are almost indistinguishable with the queens only occasionally being larger in size.
The nest of A. pallens is generally in a funnel shape with a downward facing entrance. The nest is usually attached to a leaf by a central pedicle. In general the nest is strategically placed at a diagonal in order to provide more coverage from a leaf. The nest is usually made from a mixture of salivary secretions and vegetal fibers. All social wasps use plant fiber as the primary material in the construction of their nests.
Distribution and habitat
Angiopolybia pallens is predominantly found in Brazil. They are among the most common species of wasps in this area by an overwhelming amount, as seen in multiple feeding behavior studies. The wasps prefer more humid environments and are more active when humidity levels are higher. However, the wasps are generally more active during the cooler parts of the day, like the early morning or around dusk. The nests of these wasps are typically found in rainforest environments in clearings or on the edge of the forest. A. pallens typically have nests that are large and easy to see hanging off of the branch of a tree. This means that their nests are subject to predation by ants and other animals. In order to compensate for the size and easy sighting the nests are protected from any ant predation by arboreal ants with which they share the tree.
Colony cycle
The colony cycle begins with the pre-emergence phase where the queen and a few adult workers establish a new nest. The queen already has been fertilized and is able to produce a few workers in the beginning in order to best assist with the building of the nest. The swarm starting the nest is mostly made up of adults that are already mature before the next nesting cycle begins. Then once the nesting cycle begins, the larvae and eggs are laid. Next is the worker production phase where they have the majority of eggs, larvae and pupae. This phase introduces the highest amount of reproduction and the intermediates are produced during this time. Once the nest and colony has reached maturity, the male production phase begins and the males eventually fertilize an intermediate. This fertilization distinguishes the intermediates from the queens and the colony cycle is repeated. The wasps are most active from months of July–December.