Acaenitus dubitator

Description

Acaenitus dubitator is a medium-sized, blackish, and rather robust member of Acaenitinae. White interspaces between the posterior tergites sometimes give it an almost striped appearance. The legs are predominantly red, with the hind tibiae and tarsi usually darkened. The head is broadened behind the eyes. The clypeus lacks teeth or tubercles. The areolet of the forewing is open distally (3rs-m absent). The ovipositor is longer than the abdomen, and as in all other northern European Acaenitines, the hypopygium is greatly elongated in the females. Dense but rather short black hairs covers most of the body.

Ecology

Acaenitus dubitator appears to be heavily associated with sandy grasslands and dunes and is often found in coastal environments. It parasitizes the weevil Cleonis pigra, which forms galls on the roots of several thistle species (Cirsium, Carduus). The wasp larvae overwinter within the host's gall and emerge the following summer. Adults are often found running on searching on sandy ground for their host.

Distribution

Rare but widespread in the western Palearctic.

References

ZWAKHALS, C. J., 1989. THE ACAENITINAE FROM THE NETHERLANDS AND THE HOST OF ACAENITUS DUBITATOR (HYMENOPTERA: ICHNEUMONIDAE). - EN7: BER., AMST:49 (2):21-25.

Varga, A., (2013). A review of the subfamily Acaenitinae Förster, 1869 (Hymenoptera, Ichneumonidae) from Ukrainian Carpathians. Biodiversity Data Journal 1: e1008. doi: 10.3897/BDJ.1.e1008

Skuhrovec J, Volovnik S, Gosik R, Stejskal R, Trnka F. Cleonis pigra (Scopoli, 1763) (Coleoptera: Curculionidae: Lixinae): Morphological Re-Description of the Immature Stages, Keys, Tribal Comparisons and Biology. Insects. 2019 Sep 30;10(10):325. doi: 10.3390/insects10100325.

SLU Artdatabanken (2024). Artfakta: Acaenitinae. https://artfakta.se/taxa/1000026 [2024-07-03]

Finlands Artdatacenter (2024). LAJI.FI: Acaenitinae. https://laji.fi/sv/taxon/MX.308519 [2024-07-03]

BugWeb

Acaenitus dubitator

Keys

Gallery

References