Rheotanytarsus tusimatfegeus (Sasa et Suzuki, 1999)

Tanytarsus tusimatfegeus Sasa et Suzuki, 1999: 27 (male, fig. 31a–e; Japan).

R.? tusimatfegeus Sasa et Suzuki, 1999: Makarchenko et al. 2005: 415 (Russia).

Material examined. Myohyang-san, 22–25 June 1981, 3 males, leg. W. Krzemiński.

Remarks. Neither the original description, based on simple schematic drawings, nor the photographs of the Rheotanytarsus tusimatfegeus holotype, not very successfully slide-mounted (NMNS 371:001), allow for an unambiguous definition of this species when each of the characters' source taken separately, but both in combination indicate the species analyzed here. North Korean males are slightly smaller and have a proportionally lower AR than those from Japan (wing length 1.60–1.70 vs 1.80–1.96, AR ~ 0.65 vs 0.76–0.88), while other characters are conspecific. Rh. tusimatfegeus has so far been reported from the Sea of Japan region, in Tsushima (Sasa & Suzuki 1999) and most likely in Russia (Makarchenko et al. 2005). Now recorded for the first time in North Korea.