Agriotypinae

Description

Agriotypinae is a small and highly unusual subfamily, easily recognized by several unique characters. The sternites are heavily sclerotized, making the abdomen almost appear Proctotrupid-like. The scutellum is adorned with a strong spike-like projection, and the body is covered by dense silvery hairs. The only European species, Agriotypus armatus, has four more or less distinct dark bands on the forewing.

Ecology

Members of this subfamily are ectoparasitoids of the larvae and pupae of Trichopterans. Females live a semi-aquatic lifestyle, diving into flowing water in search of their hosts. The dense hairs covering their bodies create an air bubble, allowing them to stay underwater for extended periods. Eggs are oviposited on pupae or prepupae. The larvae feed on their host from the outside during its first four stages, completely consuming it during their 5th. They then pupate and overwinter in the host's pupal case. Cases containing Agriotypines are easily recognized by a long silk ribbon extending from its opening, likely serving as a plastron. The adult wasps emerge in the spring once the water temperature reaches 10°C.

Distribution

There is only one European species, Agriotypus armatus. The remaining 15 are all found in east Asia.

References

Broad, G.R., Shaw, M.R. & Fitton, M.G. (2018). Ichneumonid wasps (Hymenoptera: Ichneumonidae): their Classification and Biology. (Handbooks for the Identification of British Insects vol. 7, part 12). Royal Entomological Society.

SLU Artdatabanken (2024). Artfakta: Agriotypinae. https://artfakta.se/taxa/253882 [2024-07-12]

Finlands Artdatacenter (2024). LAJI.FI: Agriotypinae. https://laji.fi/sv/taxon/MX.306928 [2024-07-12]

BugWeb

Agriotypinae

Keys

Northern European species

Gallery

References