New species of the non-biting midges of Tribe Chironomini (Dptera, Chironomidae) from the Bolshekhekhtsyrsky Reserve (Russia, Khabarovsk Territory) Author Orel, Oksana V. text Zootaxa 2018 2018-08-21 4461 2 269 276 journal article 28978 10.11646/zootaxa.4461.2.8 1b0d1341-ec3e-41b5-ad09-ab3cc33f0a4e 1175-5326 1460080 13EB4595-6C26-47FC-8FE3-D242CF58F824 Robackia lukini sp.n. ( Figs 6–10 , 20–23) Type material . Holotype : 1 male , Russia , Khabarovsk Territory, Bolshekhekhtsyrsky Nature Reserve , Amurskaya Channel , Sosninsky Stream , 7.VIII.2008 , leg. N.M. Yavorskaya. Paratypes : 1 male, some data as holotype; 2 males , some data as holotypes , Bykov Stream , 15.VII.2007 , leg. N.M. Yavorskaya. Derivatio nominis. The new species is named in honor of Alexander Lukin, the gamekeeper of the Bolshekhekhtsyrsky Nature Reserve, which provided a great help in collecting the material. Diagnostic characters . The species can be separated from other species of genus Robackia by the following combination of features: superior volsella 95–105 µm long, with 2 preapical setae and slightly widened membranous apex; inferior volsella elongated triangular form and densely covered with microtrichia; gonostylus knife-like, with slightly concave inner margin and protrusion in the proximal third. Description. Adult males (n=4). Total length 4.6–4.8 mm . Wing length 1.92–1.95 mm . Total length/wing length 2.36–2.50. Coloration . Flagellomere dark brown, basal segment brownish yellow; ground color of thorax and scutellum yellowish; mesonotal stripes yellowish brown; postnotum and abdomen brown; fore legs brown, sometimes median part of fe, preapical part of ti and proximal part of ta1 yellowish; middle and hind legs yellowish, ta1–5 gradually darken towards the end. FIGURES 11–15. The male of Polypedilum (s. str.) odyrensis sp.n. 11–12—apex of fore tibia; 13–14—hypopygium; 15— tergite IX and anal point. Scale bars 50 µm. Head . Head width 632 µm. Frontal tubercles absent. Antenna 1218–1323 µm long. Ultimate flagellomere 840– 945 µm long. AR 2.20–2.75. Verticals 12–20. Clypeus with 12–17 setae. Maxillary palp 632–704 µm long, lengths of last 4 palpomeres (in µm): 64; 168–192; 152–160; 248–288. HW/PL 0.96–1.00; Al/Pl 1.93–2.02. Thorax . Antepronotals 1–4, acrostichals 10–17, dorsocentrals 8–13, prealars 4–5, supraalars 1. Scutellum with 11–12 setae. Wing . Width 0.5–0.6 mm . Veins R with 4–6, R1 without setae, R4+5 with 1–2 setae. Squama with 12–16 setae; brachiolum with 2–3 setae. VR 1.09–1.12. FIGURES 16–19. The male of Polypedilum (s. str.) servatum sp.n. 16—apex of fore tibia; 17–19—hypopygium. Scale bars 50 µm. TABLE 3. Сomparative morphometric characteristics of adult males of the genus Polypedilum Kieffer

Characters/species	P . (s. str.) tochibicolor Niitsuma, 1991	P. (s. str.) adustalum Zhang & Wang, 2017	P. (s. str.) constrictum Zhang & Wang, 2017	P. (s. str.) servatum sp.n.
Total length, mm	2.5–3.2	5.15	2.83–3.65	3.5
Wing length, mm	1.7–2.3	2.55	1.70–2.27	1.9
AR	1.40–1.52	0.96	0.83–0.94	1.45
LR P1	1.58–1.66	1.74	1.89–1.97	–
Ac	19–23	17	15–18	21
Dc	19–23	21 including 4 humerals	18–28 including 4–6 humerals	14 + 5 humerals
Pa	4–5	6	5–6	6
Scts	13–16	32	13–23	16
Squama	14–21	38	27–32	13
Anal point	almost parallel-sided	constricted from distal ¼ to apex	constricted from distal 1/3 to apex	constricted from distal 1/3 to apex
Location of lateral setae on SVo	near the base	in the middle	in the middle	near the base
HR	~1.0	1.0	0.79–0.83	1.17

Legs. Spurs of middle tibia 27–31 µm, of hind tibia 27–34 µm long. Lengths and proportions of legs as in Table 4 . TABLE 4 . Lengths (in µm) and proportion of legs Robackia lukini sp.n.

P	fe	ti	ta1	ta2	ta3	ta4	ta5	LR	SV	BV	BR
P1	840–945	567–630	1134–1155	630–672	441–462	347–357	179–189	1.83–2.00	1.24–1.36	1.58–1.70	2.00–2.56
P2	756–840	735–756	420–462	210–252	147–168	84–95	63–84	0.56–0.61	3.32–3.80	3.40–4.00	2.67–2.73
P3	798–861	945–1008	672–693	336–357	252	147	95–105	0.67–0.73	2.55–2.69	2.85–3.04	3.93–4.17

Hypopygium ( Figs 6–10 , 20–23). Tergite IX without median setae. Laterosternite IX with 2–4 setae. Anal point 54–68 µm long, 17–24 µm wide, expanded in the apical 1/3, with 12–15 short dorso-lateral setae, sometimes they are also located at the base of the anal point; the projections at the base of the anal point are covered with long microtrichia and bear 3–4 setae. Gonocoxite 102–136 µm long, with 4–6 inner setae. Transverse sternapodeme 51– 68 µm long. Phallapodeme 102–119 µm long. Superior volsella length 95–105 µm, with 2 preapical setae (length 24–34 µm), located at a distance of 7–17 µm from each other, microtrichia absent; the membranous apex is slightly widened. Inferior volsella in the form of an elongated triangular lobe densely covered with microtrichia. Gonostylus knife-like, 211–228 µm long and 71–75 µm wide; the inner margin is slightly concave and has a protrusion in the proximal third, with 1 apical seta and 6 inner setae. HR 0.48–0.65. Female, pupa and larva unknown. Remarks. The new species is very different from all known species of the genus Robackia Saether, 1977 by the original structure of hypopygium, namely, by the presence of a membrane-like apical lobe on the superior volsella, by the triangular shape of the inferior volsella and the knife-shaped form of the gonostylus. Distribution . Known only from the typical habitat—Bolshekhekhtsirsky Nature Reserve ( Khabarovsk Territory).