Bizzare wingless parasitic wasp from mid-Cretaceous Burmese amber (Hymenoptera, Ceraphronoidea, Aptenoperissidae fam. nov.)

• An enigmatic wingless insect is described from mid-Cretaceous Burmese amber.
• Sting-like ovipositor and two fore tibial spurs imply placement in Ceraphronoidea.
• Multisegmented geniculate antenna and absent wasp waist indicate new family.
• Sister position regarding crown group Ceraphronoidea is theorized for the new family.
• Semicryptic, parasitoid, saltatory habits is inferred from morphological features.

A strange wingless female parasitic wasp from mid-Cretaceous Burmese amber is described as Aptenoperissus burmanicus sp. et gen. nov. in the new family Aptenoperissidae (Hymenoptera, Ceraphronoidea). Diagnostic characters of the female Aptenoperissus burmanicus sp. et gen. nov. include its wingless, streamlined and heavily sclerotized body lacking any apparent trace of a wasp waist, and geniculate antenna composed of a long, thin, stick-like scape, standard pedicel and 22 uniform flagellomeres. Also the body has 9 externally visible segments with no evidence of segment fusion implying the presence of a completely hidden segment. All tibiae have paired spurs and the hind femora are saltatory and incrassate. The double fore-tibial spur combined with unquestionable diagnostic features of Apocrita (primarily an internalized needle-like thin and acute ovipositor) suggest placement within the superfamily Ceraphronoidea s.str. with the Maimetshidae as a sister group of the crown Ceraphronoidea, composed of the Ceraphronidae, Megaspilidae, Stigmaphronidae, and Radiophronidae. The fossil is hypothesized to live semicryptically on the forest floor or tree trunk and to parasitize immature holometabolous insects. Diagnostic features of a respective male are suggested to test the hypothesized position of the new taxon.