The Guinea wasp, Polistes exclamans, is a social insect known for its structured communal living. This paper wasp species belongs to the Vespidae family within the Hymenoptera order and plays a role in various ecosystems. Understanding its biology and behavior offers insights into the world of social insects.
Recognizing a Guinea Wasp
The Guinea paper wasp, Polistes exclamans, exhibits distinct physical features. Females typically measure 13.0 to 16.5 millimeters in forewing length, and males 12.0 to 15.0 millimeters. They have slender bodies, narrow waists, and are generally brown with yellow markings on their head, thorax, and abdomen. Their antennae are banded with red, black, and yellow, distinguishing them from many other paper wasp species. Wasps in the southeastern United States often display yellow coloration on their propodeum, usually with four yellow stripes, and yellow lines on the mesonotum.
Where Guinea Wasps Live
Polistes exclamans is primarily distributed throughout the United States, extending from New Jersey south to Florida, and west to Nebraska, Colorado, Arizona, and California. Its range also includes Mexico, the Bahamas, and Ontario, Canada. This widespread distribution indicates its adaptability to various temperate and subtropical climates. These wasps prefer well-lit, open sites for nesting, frequently building paper nests in sheltered locations like under the eaves of homes or other human-made structures. They are also found in natural settings like trees, but often favor human habitation.
Life and Habits of Guinea Wasps
The life cycle of Polistes exclamans spans from spring to late fall in temperate regions, with queens overwintering in sheltered spots. In warmer areas, queens may be replaced. The colony cycle occurs between March and September, with the first workers emerging from May to July.
A single foundress queen initiates nest construction in spring, building a small nest of paper cells. The queen lays eggs, which develop into larvae and then pupae, taking approximately six to eight weeks from egg to adult. Sterile female workers then emerge, assisting in foraging, caring for subsequent broods, and maintaining the nest.
Polistes exclamans preys on caterpillars, which adults feed to the larvae. Adults also consume nectar, tree sap, and fruit juices.
Colonies are organized with three castes: males, workers, and queens. Queens typically lay all eggs and are physiologically capable of surviving colder weather for longer periods than workers. The species constructs small, open-combed paper nests, usually a single layer of hexagonal cells. These nests lack an outer envelope and are suspended by a single filament.
Ecological Role of Guinea Wasps
Guinea paper wasps play a dual role in their ecosystems as predators and incidental pollinators. As predators, they hunt insect larvae, particularly caterpillars, to feed their young. This predatory behavior helps control herbivorous insect populations, benefiting plant health and agricultural systems.
While not primary pollinators, adult Polistes exclamans feed on nectar and tree sap, inadvertently transferring pollen between flowers as they forage. This incidental pollination contributes to the reproductive success of various plant species. These wasps are also part of the food web, serving as prey for birds and susceptible to parasites like Elasmus polistis and Chalcoela iphitalis, which infest their larvae.
Guinea Wasps and People
Polistes exclamans interacts with humans, primarily due to their tendency to build nests near human-made structures. While not aggressive away from their nest, they will defend their colony if they perceive a threat. The sting of a Guinea paper wasp contains neurotoxic peptides that can cause pain and localized swelling. The impact of a sting is typically mild, resulting in temporary discomfort, but in some instances, it may lead to severe pain, dizziness, or headaches.
These wasps are considered beneficial insects for controlling pest insect populations, particularly caterpillars. However, their nesting habits near homes can lead to them being perceived as a nuisance. Coexistence involves leaving nests undisturbed in less trafficked areas or carefully relocating them if they pose a direct threat.