Chironomus flavoviridis Lundström, 1915 : 7

Saether, Ole A., 2004, The chironomids (Diptera, Chironomidae) described by Lundström (1915) from arctic Siberia, with a redescription of Derotanypus sibiricus (Kruglova & Chernovskii), Zootaxa 595, pp. 1-35 : 10

Chironomus flavoviridis Lundström, 1915: 7

( Figs. 6, 9 )

Type material. Holotype Ψ: RUSSIA: Chara­Ullach Mts., 26. vi. 1902, M. I. Brussnew.

FEMALE IMAGO (n = 1)

Total length 6.22 mm. Wing length 4.26 mm. Total length/wing length 1.55. Wing length/length of profemur 2.62. Thorax yellowish green with brownish yellow vittae; median anepisternum, preepisternum and postnotum brown. According to Lundström, first 3 segments of abdomen yellowish green, remaining segments brown with narrow yellowish green conjunctives. Legs yellowish green with apices of tibiae and all tarsi blackish brown.

Head. Antenna lost. Dorsal interocular distance 156 m, ventral interocular distance 233 m. Frontal tubercle ( Fig. 6 ) 30 m high, 19 m wide; covered with dense, but relatively short microtrichia. Temporal setae 26, consisting of 7 inner verticals, 13 outer verticals and 6 postorbitals. Clypeus with 43 setae. Tentorium 263 m long, 64 m wide; stipes 270 m long, 75 m wide. Palpomere lengths (in m): 90, 94, 233, 199, 319. Third palpomere with 8 lanceolate, 30 m long sensilla clavata in 3 separate pits.

Thorax. Antepronotal setae apparently absent. Acrostichals 26, dorsocentrals 26, prealars 12, supraalars 1. Scutellum with about 40 setae.

Wing. VR 1.11. Brachiolum with 3 setae, R with 40, R1 with 48, R4+5 with 84 setae, other veins bare. Squama with 28 setae.

Legs. Scale of front tibia 56 m long, spurs of mid and hind tibia each 68 and 56 m long including combs. Width at apex of front to hind tibiae (in m) as 101, 116,124. Sensilla chaetica about 79 on ta1 of mid leg, about 95 on ta1 of hind leg. Lengths (in m) and proportions of legs:

Abdomen. Tergite VIII with 68 setae. Sternite VIII with 112 median setae and 11 setae to each side.

Genitalia ( Fig. 9 ). Gonocoxite with 10 setae. Tergite IX with about 90 setae. Segment X with 38 setae. Cercus 263 µm long. Seminal capsule 263 µm long excluding 30 m long neck, 124 µm wide. Notum 311 µm long.

Remarks

In addition to the coloration this female differs from the other species included here by having much shorter microtrichia on the frontal tubercles and the frons. The low number of dorsocentrals (26) and few setae on squama (28) combined with the high number of setae on segment X (38) and the gonocoxite (10) separates the species from the other species described here. The front LR (1.30) and SV (1.74) separate the female clearly from C. trabicola (LR 1.04, SV 1.91), but less from C. lugubris sensu Lundström (LR 1.45, SV 1.50). Although Lundström hesitated describing a new species based on a single female he points at the extreme rarity of green Chironomus species in arctic areas.

Figures

FIGURES 1 – 10. Chironomus (Chironomus) spp., imagines, 1: C. lundstroemi sp. n., hypopygium, 2 – 6: frontal tubercles and frons, 2: C. lundstroemi sp. n., female, 3 – 4: C. trabicola Shobanov, Wülker & Kiknadze, female and male, 5: C.? lugubris Zetterstedt, female, 6: C. flavoviridis Lundström, female, 7 – 10: female genitalia, apodeme lobe (shown separately), dorsomesal and ventrolateral lobes, 7: C. lundstroemi sp. n., 8: C.? lugubris Zetterstedt, 9: C. flavoviridis Lundström, 10: C. trabicola Shobanov, Wülker & Kiknadze.