Stenogastrinae

Stenogastrinae, commonly known as stenogastrine wasps, is a subfamily of wasps in the family Vespidae, order Hymenoptera. The group includes several genera, with Stenogaster as the type genus. Historically, Stenogastrinae has been treated by some authors as a separate family (Stenogastridae), but in modern classifications it is placed as a subfamily within Vespidae. Molecular and morphological data support its status as a relatively early-branching vespoid lineage, contributing to understanding of eusocial evolution.

Distribution and habitat: Stenogastrinae is predominantly tropical, with most species occurring in Asia and Africa and occasional records in other tropical regions. Habitats include forested areas, where nests are typically located in sheltered spots such as tree hollows, leaf shelters, or under bark.

Biology: The degree of sociality in Stenogastrinae ranges from solitary to primitively eusocial. Some species build small colonies with little or no morphological differentiation between queens and workers; reproduction and caretaking duties may be shared or not strongly organized into castes. Adults forage for nectar and prey for the larvae, typically immobilizing prey to provision brood cells.

Nests: Nests are usually constructed from plant materials bound with saliva or other secretions, and may be enclosed or partially shielded. The structure and exact materials vary among genera.

Relation and study: Stenogastrinae is of interest for studies of eusociality and vespoid evolution. Ongoing research, including molecular analyses, continues to refine the relationships among vespoid subfamilies and the placement of Stenogastrinae within Vespidae.