Wiedemannia (Wiedemannia) caucasica Joost

(Fig. 3)

Wiedemannia caucasica Joost, 1981: 186 .

Material examined. RUSSIA: Adygea Republic, Caucasian State Nature Biosphere Reserve (4), 25.vii.2013, S. Kustov (1 ♂). Krasnodarskiy Territory, River Malaya Laba (10), 24.v.2014, D. Zherebilo (3 ♂, 5 ♀); northern slope of Rocky Ridge (22), 24.v.2014, D. Zherebilo (3 ♂, 5 ♀). Karachay-Cherkess Republic, env. Phiya (15), 11.viii.2013, D. Zherebilo (5 ♂, 15 ♀); same data, V. Gladun (3 ♂, 7 ♀). GEORGIA: Lechkhumi ridge (41), 29.iv.2014, D. Zherebilo (14 ♂, 21 ♀); env. Lahepa (23), 29.iv.2014, D. Zherebilo (4 ♂, 4 ♀); Mingrelia (28), 2.v.2014, D. Zherebilo (3 ♂, 1 ♀); same data, 6.v.2014, D. Zherebilo (3 ♂, 5 ♀); ridge Ofitsari (30), 828 m a.s.l., 4.v.2014, D. Zherebilo (5 ♂, 9 ♀); same data, 6.v.2014, D. Zherebilo (1 ♂); env. Zedakinchha (34), 9.iv.2015, A.V. Zherebilo (2 ♂, 1 ♀); env. Opitara (35), 10.iv.2015, A.V. Zherebilo (1 ♂); env. Chkumi (36), 11.iv.2015, A.V. Zherebilo (2 ♂, 3 ♀); env. Namohvani (37), 15.iv.2015, A.V. Zherebilo (4 ♂); env. Mukhuri (42), 17.iv.2015, A.V. Zherebilo (6 ♂, 9 ♀); env. Norio (46), 18.iv.2015, A.V. Zherebilo (1 ♂); Lechkhumi ridge (41), 19.iv.2015, A.V. Zherebilo (6 ♂, 9 ♀); env. Orhvi (39), 20.iv.2015, A.V. Zherebilo (5 ♂). ABKHAZIA: River Bzyb (11), 11.vii.2013, D. Zherebilo (1 ♀).

Diagnosis. Wiedemannia (s.str.) caucasica differs by the gena equal to eye height, acrostichals divergent around the prescutellar depression, 5 pairs of dorsocentrals with interspersed shorter setae, olive-brown scutum with blue pruinescence on prescutellar depression, fore femur without strong anterior setae apically; pterostigma indistinct and elongate; clasping cercus unilobed, extending to tip of phallus, broader at base, without basal process.

Distribution. Caucasus: Russia (Adygea Republic, Krasnodarskiy Territory, Karachay-Cherkess Republic), Abkhazia, Georgia.

Remarks. Joost (1981) described this species from the Sochi River (Russia, Krasnodarskiy Territory), but in the Catalogue of Palaearctic Diptera (Chvála & Wagner 1989) the species was mistakenly indicated from the territory of Georgia. Therefore W. caucasica is noted from the territories of Georgia and Abkhazia for the first time. This commonly collected species is known from submontane and mountain rivers from altitude 0–1700 m a.s.l. and active from April to August.