Parorthocladius lazovskiensis Makarchenko et Makarchenko

Makarchenko, Eugenyi A. & Makarchenko, Marina A., 2015, A review of the genus Parorthocladius Thienemann, 1935 (Diptera: Chironomidae: Orthocladiinae) from the Russian Far East, Zootaxa 3974 (3), pp. 413-423 : 414-415

Parorthocladius lazovskiensis Makarchenko et Makarchenko , sp. nov.

( Figs. 1–3 )

Material. Holotype: adult male, Russian Far East, Primorye Territory, Lazovsky District, Lazovsky State Nature Reserve, Priamushka River, 19–20.V. 2007, leg. O. Zorina. Paratypes: 1 adult male, Primorye Territory, Ussuryisky District, Ussuryisky State Nature Reserve, Peishula River, 28.VII. 1998, leg. T. Vshivkova; 1 adult male, Sakhalin Island, Tymovsky Region, Khrebtovy Stream (Chamgu River basin), 28.VII. 2003, leg. E. Makarchenko.

Adult male (n=3). Total length 2.65–3.25 mm. Wing length 2.0– 2.08 mm. Total length/wing length 1.3–1.6.

Head. Temporal setae 13–14, including 10 verticals and 3–4 postorbitals. Clypeus with 7 setae. Antenna with 13 flagellomeres and well developed plume; AR 0.96–1.1. Palp with 5 palpomeres. Length of distal 4 palpomeres (in µm): 48, 92, 84, 140 (n=1).

Thorax. Scutum with 3 dark brown stripes on yellowish or brownish yellow surface. Antepronotum with 2–3 lateral setae. Dc 6–8; Pa 4; scutellum without setae.

Wing. R with 5–6 setae, R1 and R4+5 without setae. Cu1 slightly curved in distal part. R4+5 ending slightly distal or above apex of M3+4. Costa extension 40 µm. Anal lobe well developed, rectangular-rounded. Squama with 10–16 setae.

Legs. Spur of fore tibia 56 µm. Spurs of mid tibia 20 µm and 24 µm long, of hind tibia 24 µm and 56 µm long. Hind tibial comb with 10 setae. Fore leg without pseudospurs on ta1; mid and hind legs with 2 apical pseudospurs on ta1. Sensilla chaetica on mid leg absent. Lengths and proportions of leg segments as in Table 1 .

Hypopygium ( Figs. 1–3 ). Tergite IX and anal point with 10–15 setae. Anal point 24–36 µm long and 8–12 µm wide near apex. Laterosternite IX with 4–7 setae on each side. Transverse sternapodeme 80–92 µm long, with triangular oral projections. Virga 24–28 µm long, consists of 2 short setae. Gonocoxite 184–196 µm long; dorsal part of inferior volsella nose-like; ventral part of inferior volsella located at dorsal part of inferior volsella ( Fig. 1 ). Superior volsella developed and rounded ( Fig. 2 ). Gonostylus 80 µm long, with low preapical crista dorsalis; megaseta 8 µm long.

Diagnostic characters. The new species is most closely related to the Palaearctic species P. nudipennis and can be distinguished from the latter by the presence of virga, double inferior volsellae, well-developed superior volsellae, the absence of scutellars, the presence of vertical setae of the head, as well as by the shape of crista dorsalis (preapical and triangular) and the shape of the anal point - tapering towards slightly rounded tip. Adult male of P. nudipennis differs from P. lazovskiensis in having no virga, inferior volsellae simple, superior volsellae indistinct, scutellars present, vertical setae of the head absent, crista dorsalis weak and low, and anal point parallelsided ( Brundin 1956, Serra-Tosio 1981, Liu & Wang 2005).

Etymology. The species is named lazovskiensis in honour of the Lazovsky State Nature Reserve.

Distribution. Known from the type locality in Sakhalin Island, Primorye and Khabarovsk Territories of the Russian Far East.

Figures

FIGURES 1 – 7. Parorthocladius lazovskiensis sp. nov., male (1 – 3) and P. plolabius sp. nov., male (4 – 7). 1, 6, hypopygium in dorsal view; 2, gonocoxite and gonostylus in dorsal view; 3 – 5, anal point; 7, part of hypopygium without tergite IX in dorsal view. 1, male from Sakhalin Island; 2 – 3, male from Primorye Territory; 4 – 7, males from Amur River basin. Scale bars – 50 µm.

Tables

TABLE 1. Lengths (in µm) and proportions of leg segments of Parorthocladius lazovskiensis sp. nov., male (n = 2).

fe	ti	ta1	ta2	ta3	ta4	ta5
P1 688	784–816	576–592	416	288–304	208–224	128
P2 672–704	736	384–416	256	208	160	128
P3 752–768	864–880	488–512	304	240	160	128
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