Arcotomus

Taxonomy

Acrotomus succinctus is a parasitic wasp in the subfamily Tryphoninae in the family Ichneumonidae. The geographic range of A. succinctus spans across Europe, Asia, North Africa and North America. In North America, they are primarily found in regions of the United States and Canada. 

Description

Acrotomus succinctus are smaller Ichneumon wasps. They usually range in length from 5 to 7mm. Their head, thorax, and abdomen are mostly black, while their face, clypeus, and mandibles are yellow. Various parts, such as the pronotum's anterior edge, tegulae, wing base, and others, also exhibit yellow markings. Yellow-brown markings appear on certain areas like the femora and tibiae, while the posterior tibia and tarsi tend to darken. Tergites 2 to 6 feature a thin yellow border at their rear. Both sexes display yellowish lateral edges on their posterior abdominal segments, with males having a yellow ventral abdomen and females a brown one. Notably, the forewings exhibit a distinctive venation with a small rectangular areola, and the pterostigma's basal end is yellow. 

Nest Structure

Most Ichneumonids are parasitoids whose larvae feed and develop on a single host, although some species' larvae are mobile and will feed on more than one host. Hosts include a wide range of insects in the orders Hymenoptera, Lepidoptera, Diptera, Coleoptera, Neuroptera, and Mecoptera, and spiders and spider egg sacs. Most Ichneumonids are solitary. We had three nests that were parasitized by Arcotomus succinctus in the Bee Atlas project, but we did not get any information about the insect host from them.

Hole Sizes

No information at this time.

Voltinism

No information at this time.

Activity Period

No information at this time.

References

Triplehorn, C.A and N.F. Johnson. 2005. Borror and DeLong's introduction to the study of insects, 7th ed. Thomson, Brooks/Cole, Australia. 

BugGuide. 2024. "Species Acrotomus succinctus”- BugGuide.Net." Accessed May 17, 2024. https://bugguide.net/node/view/2077332

Discover Life. 2024. "Ichneumonidae." In Proceedings of the Ecological Society of America, vol. 6. Accessed May 17, 2024. https://www.discoverlife.org/proceedings/0000/6/html/Ichneumonidae.html

Gupta, V. K. 1991. A review of the Exenterine Genus Acrotomus Holmgren 1855 (Hymenoptera, Ichneumonidae). Entomofauna 12(3): 33-48.

Thank you to John Luhman for identifying all of our Ichneumonid specimens.