Erimerus luteus ( Bouček, 1954 )

Erimerus luteus ( Bouček, 1954) View in CoL

Figs 36–39

Material examined. 7 ♀♀, 3 ♂♂: IRAN, West-Azarbaijan Province , Naqadeh, Solduz Wetland, 37º02′ N, 45º35′ E, 1277 m a.s.l., 21 July 2020, 29 April 2021, M. Razmi leg., ex Calamagrostis epigejos GoogleMaps .

Diagnosis (abstracted from Bouček 1954; Zerova and Seryogina 1990, 2008). The key diagnostic features that distinguish females ( Fig. 36A) of this species include: body entirely lemon-yellow, including antennae ( Figs 36A,B,

37E) and legs ( Fig. 36A); ovipositor sheaths extending slightly beyond gaster (almost not extending beyond it) ( Fig. 36A); and antenna with three transverse anelli ( Fig. 36B).

Males ( Fig. 38A) and females are similar in terms of both size and body color. Notable distinguishing characteristics between the sexes consist of the shape of gaster and a slight difference in the shape of the antennae ( Fig. 37B).

Remarks. Bouček’s (1954) description of the male states that certain body parts of the male are darker than those of the female, including the margins of the ocelli, occiput, collar region of pronotum ( Fig. 38E), two spots on the anterior margin of the mesoscutum, anterior halves of the scapulae, the anterior portion of the axillae, the central area of the propodeum ( Fig. 39 A,B), and the more or less anterior part of the gaster ( Fig. 39E). However, our specimens exhibit some differences. Some of the described darker areas of males, such as the collar region of the pronotum, the mesoscutum, and the axillae, are also observed in females ( Figs 36A, 37A,B). Furthermore, the males are slightly larger than previously reported in the description and previously documented for this species. This suggests that the previously described sexual dimorphism in coloration may not be as pronounced or consistent as initially reported, highlighting the need for further examination of morphological variations within the species.

Distribution. IRAN: West Azarbaijan Province ( new record). EXTRALIMITAL: Europe, Morocco ( UCD Community 2023).

Biological association. Given the observed presence of Cecidomyiidae gall-makers Lasioptera calamagrostidis on Calamagrostis ( Karimpour et al. 2024) and the documented history of this parasitoid’s biological associations, the evidence suggests that L. calamagrostidis serves as a host for this species. As a primary parasitoid of Hessian fly on Hordeum spp. ( Poaceae ), this species plays a significant role in its biological control, a major pest of barley ( Grissell 1995; Askew et al. 2001; Narendran et al. 2012). The interaction between this parasitoid and its host within the context of Hordeum grasses highlights its ecological importance in agricultural ecosystems. Further studies on its behavior, life cycle, and efficacy as a biological control agent are essential for optimizing its use in integrated pest management strategies.