Spinarge Wei, 1998

Spinarge Wei, 1998

Figs 5 View Figs 2–15 , 17–18 View Figs 16–24 .

Type species: Spinarge sichuanensis Wei, 1998 .

Body size 7.2–11.9 mm. Antennae of males simple. Fore wings with 4 cells Rs; cell R closed; vein Sc present; vein 2r–m present; cell 2A closed. Cell A of hind wing closed. Hind tibiae with or without preapical spurs. Fifth abdominal tergite of male has a long medial process, in females represented by a scarcely noticeable triangular swelling and inconspicuous median groove on tergites 4–6. Hind tibia with or without preapical spur.

Representatives of this genus are very similar to the closely related genus Arge . Furthermore, whereas the males have a pronounced process of the 7 th tergite, which makes it possible to reliably place them in Spinarge , in females the corresponding character is very weak and in some cases can be confused with folds and deformations of the abdomen caused by drying. In collections, females significantly predominate, while males are rare, which in our experience leads to a large number of erroneous identifications.

The genus is distributed in the Palaearctic and Oriental regions. Number of species: World — 13; Palaearctic — 10. Since the publication of the world catalogue of sawflies [ Taeger et al., 2010] two new species have been described [ Liu et al., 2021; Vasilenko, 2022]. New data on the distribution and biology of members of the genus were also published [ Shinohara, Hara, 2012; Shinohara et al., 2016]. Spinarge acutithecata Wei, 2010 and Spinarge xanthofemorata Wei, 2010 have been reported as new taxa [ Wu et al., 2010], but their descriptions have not been published to date. They should be considered as nomina nuda.

In the latest key to Argidae genera for Europe [ Lacourt, 2020], the thesis “hind tibiae without preapical spurs” leads to the genus Spinarge . This is erroneous, because, as noted by Hara and Shinohara [2006], only two species actually do not have them, while the rest, including the only one inhabiting Europe, Spinarge metallica (Klug, 1834) , have such spurs. This makes it impossible to correctly determine the genus according to that key. In all existing keys for Russia [ Gussakovskij, 1935; Zhelochovtsev, 1988], the species of the genus Spinarge are considered as part of the genus Arge .