Cleruchus Enock, 1909

Comments. Detailed taxonomic history of Cleruchus, including synonymy, is given in Triapitsyn (2014a), with Bakkendorfia Mathot subsequently synonymized under Cleruchus by Huber & Triapitsyn (2017).

Diagnosis. Body dorso-ventrally flattened; female funicle 6-segmented and clava entire (Fig. 2); mandible uni- or bidentate; fore wing more or less parallel-sided, usually knife-like (Fig. 3), at least about 8× as long as wide; femora slightly swollen; ovipositor usually short and often arising in apical third of gaster (Noyes & Valentine 1989 and Lin et al. 2007).

Cleruchus belongs to the Cleruchus group of genera, which includes Ceratanaphes Noyes & Valentine, Cleruchoides Lin & Huber, Cleruchus Enock, Cybomymar Noyes & Valentine, Nesomymar Valentine, Paracmotemnus Noyes & Valentine, Prionaphes Hincks, and Pseudocleruchus Donev & Huber (Lin et al. 2007), as well as, at least, Apoxypteron Noyes & Valentine and Platystethynium Ogloblin. It is similar to Cleruchoides Lin & Huber, according to Lin et al. (2007), in having a fore wing disc that is mostly bare, with only one or two rows of microtrichia, but can be differentiated by the fore wing being parallel-sided, knife-like, and at least 8× as long as wide, with the posterior margin having a weak lobe behind the apex of venation (fore wing with anterior and posterior margins diverging, about 6× as long as wide, and posterior margin distinctly lobed behind the apex of venation in Cleruchoides). Cleruchus is also close to Pseudocleruchus from which it can be differentiated based on characters given in Pricop (2011).

Unlike in most other genera of Mymaridae except a few genera like Mymar Curtis, males of Cleruchus are often diagnostically important—e.g., the number of flagellar segments was used by Triapitsyn (2014a) in his key to the Palearctic species of the genus.

Biology. The known hosts for Cleruchus so far are Curculionidae (Schauff 1989; Barnes 2014), Cleridae (Huber 1986), and Ciidae (Triapitsyn 2002) in Coleoptera as well as Acrididae in Orthoptera (Huber 1986) . Cleruchus pieloui (Yoshimoto) was reared from the birch bracket (polypore) fungus, Piptoporus betulinus, in New Brunswick, Canada (Yoshimoto 1971). Cleruchus polypori Triapitsyn & Moraal was reared from the fruiting bodies of the bracket fungus Fomes fomentarius on Fagus sylvatica old trees in the Netherlands; C. puchus Triapitsyn was reared from eggs of undetermined cultured Ciidae beetles associated with a Polyporus sp., and also from the bracket fungus Trametes versicolor in California, USA (Triapitsyn & Moraal 2008).