This is a hymenopteran insect belonging to the family Vespidae, characterized by a slender and robust body with a total length ranging between 15 and 22 millimeters. Its general coloration is predominantly reddish-brown or ferruginous, accented by bright yellow bands or markings distributed conspicuously on the abdomen, the posterior margin of the pronotum, and the clypeus. The wings exhibit a smoky or amber tint with dark venation. It displays clear morphological sexual dimorphism; males possess antennae with curved tips and a lighter facial region compared to females, who bear a functional stinger modified from their ovipositor.
Geographical distribution: It is widely distributed across the southern cone of South America, spanning a vast region that encompasses central and northern Argentina, extending throughout the entire territory of Uruguay, southern Paraguay, and the southernmost states of Brazil, particularly Rio Grande do Sul. Its geographic range demonstrates a remarkable adaptability to different climatic gradients, ranging from humid temperate zones to subtropical regions.
Habitat: It inhabits a variety of environments, ranging from natural ecosystems such as grasslands, savannas, open woodlands, and shrublands, to biomes heavily modified by human activity. It is particularly common in urban and suburban areas, where it takes advantage of artificial structures such as building eaves, roofs, window frames, and utility poles to establish its colonies, finding a favorable microclimate and protection against adverse weather conditions.
Feeding: It exhibits a dual dietary regime that varies drastically depending on the developmental stage and caste. Adults are primarily glucophagous and phytophagous, feeding on carbohydrate-rich sources such as flower nectar, plant sap, aphid secretions, and ripe fruit juices. In contrast, the larvae are strictly carnivorous and depend on the protein supply provided by the workers, which actively hunt a wide variety of prey, particularly lepidopteran caterpillars and other soft-bodied insect larvae, masticating them into a soft bolus before feeding them to the offspring.
Behavior: It is a eusocial species that organizes its life in seasonal colonies of moderate size. Unlike other more aggressive vespids, it shows a relatively peaceful temperament, attacking only when the nest is directly disturbed. It has the ability to construct open, single-comb nests without an external envelope, made from a paste of masticated plant fibers mixed with saliva, resulting in a paper-like or cardboard texture. Intra-colony communication is conducted through chemical signals (pheromones) and physical vibrations on the comb.
Reproduction: The reproductive cycle begins in early spring when a fertilized founding female (queen) that survived the winter in a state of diapause emerges from her shelter to initiate a new nest solitarily. She deposits a single egg in each hexagonal cell of the initial structure. After hatching, the foundress feeds the first larvae until they pupate and emerge as sterile female workers, at which point the queen dedicates herself exclusively to egg-laying. Towards late summer and early autumn, the colony begins to produce reproductive individuals: males and future queens (gynes). These perform nuptial flights where mating occurs; subsequently, the males and the workers of the old colony perish with the arrival of cold temperatures, while the newly fertilized queens seek shelter under tree bark or building crevices to overwinter.
Conservation status: It has not been formally evaluated by the International Union for Conservation of Nature (IUCN), and therefore lacks an official classification on the Red List. However, due to its wide distribution, high ecological resilience, local abundance, and remarkable ability to adapt to anthropic environments, its populations are considered stable and under no immediate threat of extinction, additionally serving as a valuable agent for the biological control of agricultural and garden pests.
Compilation and publication: EcoRegistros – 16/08/2026