Native Ropalidia Wasps
Rhopalidia wasps native to the Old World include rhopalidia marginata. It exhibits less predation in brood care than other social insects with greater relational asymmetry, indicating that it is socially primitive. The species uses various colony-forming techniques, sometimes using solitary founders and other times using groups of varying sizes. The queen is shown to use pheromones to prevent other workers from usurping her as queen, rather than physical dominance to control the workforce. These wasps also attach their nests to tree structures, especially under eaves. Individual combs are found in rows and often appear as vertical bands 2 cells wide and of varying length. These nests are made by mixing saliva with chewed wood to form a cardboard-like material. Different animals build their nests in different ways. When their nests are threatened, these wasps fiercely defend them.
The Rhoplidia wasp has a small head, medium-sized eyes, and medium-length antennae in its natural habitat. The waist is very small, and the body is slim. Two pairs of brown wings are present, the first pair being the largest. Although they are mostly black, there are some yellow or orange bands on the abdomen. Recent reports of invasive Rhopalidies Asian wasps (Polistes chinensis) have come from several inner-city Sydney suburbs. This closely related species tend to have more pronounced yellow and brown stripes and are larger than the local Polistes.
The life cycle of the native Ropalidia wasp builds paper nests under tree branches and on the eaves of houses in small colonies. The nests, which look like inverted cones, are formed from a set of hexagonal cells containing a mixture of saliva and wood fibers. Worm-like wasp larvae develop in the papery cells of the nest.
Native Rhopalodia wasps can be found in grasslands, forests, and cities. Australia is home to the native Rhopalidia wasp. While adult wasps feed native Rhopalidia wasp larvae by capturing caterpillars, the adults themselves consume nectar. Native Rhopalidae wasps build their nests in a succession of cells that resemble an inverted cone and are made of saliva and small pieces of wood. Once dried, the decoction takes on a papery consistency, which gives these wasps their name. Although they can sting painfully, native Rhopalodia wasps are not as aggressive as European wasps. Generally, they only attack those who disturb their nest. However, multiple stings can cause a more serious systemic reaction. Wasp, bee, and ant stings can sometimes cause an allergic reaction (anaphylaxis), but this is not common. There is an effective therapy that involves carrying special equipment outside for people known to be allergic to bee, ant, or wasp stings. Desensitization or immunotherapy are other options that can reduce the intensity of allergies.