Aprostocetus catius (Walker, 1839)

Razmi, Mehdi, Karimpour, Younes & Lotfalizadeh, Hossein, 2025, Bushgrass, Calamagrostis epigejos (Poaceae), a natural pool of chalcidoid wasps (Hymenoptera: Chalcidoidea) in Iran, Zootaxa 5696 (2), pp. 151-204 : 167-168

Aprostocetus catius (Walker, 1839)

Fig. 12

Material examined. 79 ♀♀, 90 ♂♂: IRAN, West-Azarbaijan Province , Naqadeh, Solduz Wetland, 37º02′ N, 45º35′ E, 1277 m a.s.l., 21 July 2020, 29 April 2021, Y. Karimpour leg., ex Calamagrostis epigejos .

Diagnosis (abstracted from Walker 1844; Graham 1987). The female of A. cutius ( Fig. 12B,D ) differs from A. emesa (Walker, 1839) exclusively in two diagnostic characters given in the female identification key provided by Graham (1987), namely: the relative lengths of the ovipositor sheaths and postcerci compared to the metatibia (0.40–0.63× and 2.9–3.6×, respectively), and the proportional lengths of the fore wing marginal vein versus the stigmal vein (0.75–0.90× and 3.6–4.0×, respectively). Additionally, the gaster (excluding the ovipositor sheaths) is 1.3–1.5× as long as the combined length of the head and mesosoma and 2.6–2.9× its own width, with slightly curved lateral margins in its distal portion. To date, the male of this species has remained undescribed, and its biology is unknown; however, this study presents the first description and photographic documentation of the male.

Males ( Fig. 12A,C ) exhibit comparable coloration and dimensions to those of females: scape 2.5× its width outer surface with several setae positioned away from the ventral edge, and with. a ventral plaque approximately one-third the length of the scape; combined length of the pedicel and flagellum about 2.2× width of the mesoscutum; pedicel approximately1.9× as long as wide, distinctly exceeding length of Fu 1; pedicel noticeably thicker than funicle and filiform in shape. Fu 1 slightly shorter than Fu 2 and 1.5× its width, and subsequent funicular segments nearly equal in length, each about twice as long as their width; clava marginally wider than Fu 4, its length equivalent to that of Fu 3 plus Fu 4, and approximately four times as long as wide; C 1 and C 2 equal in length, each 1.2× its width, C 3 relatively short, nearly equal in length and width; and gaster pale, 1.5× the length of mesosoma, and twice as long as wide.

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

Biological association. No host associations have been formally documented for this species. However, existing host records of congeneric species are Diptera , specifically Cecidomyiidae and Agromyzidae ( Graham 1987; UCD Community 2023). Considering that specimens from both dipteran families were collected from Calamagrostis spp. , there is a probable ecological association between this genus and these gall-forming/flower-head inhabiting dipterans.

Figures

FIGURE 12. Aprostocetus catius (Walker). A. Male in lateral habitus. B. Female in lateral habitus. C. Male in dorsal habitus. D. Female in dorsal habitus. E. Male fore wing. F. Male head and mesosoma in dorsal view. G. Female head and antennae in lateral view.