Beckidia tethys (Townes) (Figs. 6–7) Harnischia (Cladopelma) tethys Townes, 1945: 152, fig. 174. Beckiella tethys (Townes); Saether, 1977: 120, fig. 44. Beckidia tethys (Townes); Saether, 1979: 119; Cranston et al. 1989: fig. 10.6; Makarchenko et al. 2005: 394. Material examined: 1 male, RUSSIA, Khabarovsk Territory, Ussury River near Zabaykalskaya Village, 25.vii.2003, T. Tiunova; 1 male, Primorye Territory, Khanka Lake near Astrakhanka Village, 26.viii.1996, E. Makarchenko; 3 males, Khanka Lake near Turiy Rog Village, 12.vi.1998, T. Vshivkova. Previous descriptions of B. tethys are brief, so below I give a more detailed description based on the specimens from the Russian Far East. Male (n = 3) Total length 3.0– 3.3 mm. Wing length 1.3–1.4 mm. Total length/wing length 2.1–2.5. Coloration. Scapus yellowish, flagellomeres dark brown; ground color of thorax pale yellow, mesonotal strips and two­third of postnotum yellowish brown; front leg brownish except for pale yellow femur; mid and hind legs with pale yellow femur and tibia, ta1–5 gradually darker toward apex; abdomen yellowish. Head. Frontal tubercle absent. Verticals 8–11. Clypeus with 6–8 setae. Antenna 895– 916 m long, AR 1.63–1.82. Maxillary palp 440 m long, lengths of segments II­V (in m): 40, 80, 110–130, 190. Palp length/head width 0.85, antenna length/palp length 2.03. Thorax. Antepronotals 0, acrostichals 0, dorsocentrals 6–8, prealars 2–3, supraalars 1. Scutellum with 3–8 setae. Wing. Width 0.43 mm. VR 1.03–1.22. R with 2–4 setae, R1 without setae, R4+5 with 2 apical setae, brachiolum with 2 setae. Squama with 2–5 setae. Legs. Combs of median and hind tibiae with 2 spurs, 18–23 m long. LR1 1.94­2.0, LR2 0.64, LR3 0.73; SV1 1.37–1.38, SV2 3.36, SV3 2.64; BV1 1.67–1.69, BV2 3.21, BV3 2.22; BR1 2.89–3.13, BR2 5.0, BR3 5.0. Hypopygium (Figs. 6–7). Anal tergite bands of H­type. Anal point 50–70 m long, 9 m wide, placed preapically on tergite IX. Laterosternite IX with 1–2 setae. Transverse sternapodeme 41–45 m long. Gonocoxite 90–95 m long, with 3–4 setae. Superior volsella pad­like, 32 m long, 32–36 m wide, with 11–15 setae and microtrichia, partially fused with inferior volsella. Gonostylus 126–153 m long, 23–27 m wide, curved, widest medially. HR 0.63–0.66. Distribution The species has previously been recorded from Canada and USA in the Nearctic Region and from Serbia in the Palaearctic Region (Saether et al. 2000). The species is recorded for the first time from Russia.

Published as part of Zorina, Oksana V., 2006, New species and records of Beckidia Saether (Diptera: Chironomidae) from the Russian Far East, pp. 47-53 in Zootaxa 1151 on pages 52-53, DOI: 10.5281/zenodo.172151