Retinoinae

Retinoinae is a subfamily of ichneumonid wasps in the family Ichneumonidae, order Hymenoptera. It was proposed in the late 20th century to classify a group of genera sharing certain morphological traits, but its recognition remains disputed among ichneumonid taxonomists.

Members are small to medium-sized wasps, typically 5–15 mm in length, characterized by a slender mesosoma, sculptured propodeum, and distinctive wing venation patterns, with a generally smooth or weakly sculptured metasoma. Females usually possess a long ovipositor or blade-like apparatus adapted for oviposition into hosts concealed within plant tissue, wood, or soil.

Retinoinae species occur in temperate to subtropical regions across multiple continents. They are parasitoids, with the larval stage developing inside the larvae of Lepidoptera and occasionally other insect orders. The life cycle includes egg, larval, pupal, and adult stages, synchronized with host availability.

The circumscription of Retinoinae varies by author; some recognize it as a stable subfamily, while others treat it as a junior synonym or as a tribe within a broader subfamily. The subfamily is currently believed to comprise several genera distributed in different biogeographic regions; precise relationships to other ichneumonid subfamilies remain uncertain.

As parasitoids, Retinoinae contribute to natural control of pest species and play roles in ecosystem regulation. Ongoing revisions in ichneumonid systematics aim to clarify their evolutionary relationships and species boundaries.