Rhopalum

Rhopalum is a genus of potter wasps belonging to the family Vespidae. These wasps are characterized by their relatively slender bodies and their distinctive nesting behavior. Rhopalum wasps are solitary, meaning each female builds and provisions her own nest independently, unlike social wasps that live in colonies.

The nests of Rhopalum are typically constructed from mud or a mixture of mud and saliva, hence the common name "potter wasp." They often build their nests in pre-existing cavities such as hollow stems, abandoned beetle burrows, or even in crevices on buildings. The female wasp collects small pellets of mud and carefully molds them into a pot-like structure. Once the pot is formed, she provisions it with paralyzed prey, usually small insects or spiders, which she has hunted and stung. After laying a single egg within the nest, she seals it with mud. Each nest may contain one or more cells.

The larvae that hatch from the eggs feed on the stored prey until they mature. The adult Rhopalum wasps are predators and feed on nectar and other sugary liquids for energy. They are found in various regions, with species distributed across different continents. Identification of individual species within the genus Rhopalum often relies on subtle morphological differences, such as the shape and markings of the abdomen and thorax. Their ecological role includes controlling populations of their prey insects and spiders.