Spilogona vikhrevi Sorokina 2010

Spilogona vikhrevi Sorokina, 2010

(Figs 11–13)

Spilogona vikhrevi Sorokina, 2010: 35, figs 1–3. Type-locality: Russia, Archangel’skaya oblast’, Nenezkyi AO, 60 km N Naryan-Mar.

Described from 2 males from the northern European Russia, but VS has now discovered a large number of Spilogona vikhrevi, including specimens of the previously unknown female, in K.B. Gorodkov’s collection of Diptera from Wrangel Island kept in ZISP. Some supplementary characters of the male and a description of the female are given below.

Male ( Fig. 11). Genal height about ½ of eye height. Frontal vitta 1.5–2 times wider than diameter of anterior ocellus. Notopleuron bare or with a few setulae. Scutellum with preapical setulae on upper border of declivities. Fore tibia with 0–1 p seta. Mid femur with 6–10 pv setae; mid tibia with 0–2 ad and 0–2 very short v setae. Hind femur with 7–10 av, 3–5 hair-like pv setae on basal half; hind tibia with 2–3 ad, 2–3 av and 6–7 pd setae of different lengths on apical half (1 longer pd seta in middle). Sternite I with 2 setulae. In some specimens all setae on the legs are very short. Some specimens have basally curved tibiae.

Female (Figs 12, 13). Very similar to male in body size and chaetotaxy, but very different in general appearance due to thick golden greyish dust on head and body that makes it resemble a scathophagid dung fly. Head: Width of frontal vitta equals width of fronto-orbital plate; frons with 3 pairs of strong orbital setae followed by 3–4 hair-like orbital setae reaching base of antennae; frontal setae in two uneven rows. Width of parafacial at level of antennal base 1.5 times width of postpedicel. Height of gena variable, ranging from ½ –¾ of eye height (Figs 12, 13). Thorax: Scutum with 3 narrow dark stripes. Wing with a light brownish tinge. Upper calypter brown; lower calypter fuscous yellow. Haltere light yellow or brownish. Legs: Fore tibia with 1–3 p setae, sometimes also with some short and spinulose v, av and pv setae. Mid tibia with 2 ad, 2–5 pd, 2 v, 2 av and 1 pv setae. Hind tibia with 2 pv setae. Abdominal dusting ranging from golden to yellowish grey, if golden then with indistinct paired dark marks visible on tergites III–V. Postgenital plate without spines, only with short and fine setulae.

The species can be incorporated into Hennig’s (1959a: 266) key to females of Palaearctic Spilogona by the following couplets:

29 (26) as in Hennig.

29a (33) Anepisternum with interspatial setae.

29b (30) Anepisternum with 1 long and strong interspatial seta; body covered in dense golden or golden grey dusting; frons with 3 pairs of strong orbital setae and 3–4 additional hair-like orbital setae reaching antennal base. Larger, wing length normally more than 5 mm.............................................................. Spilogona vikhrevi Sorokina

30 (31) Anepisternum with 2 (sometimes with 1) strong interspatial setae; body covered in darker, greyish to brownish black dusting; frons at most with 2 orbital setae. Smaller, wing length less than 5 mm................................... 31

31 (32) as in Hennig.

Material examined. RUSSIA, Wrangel Island, 1 male 8 females, 4 km S Sovetskaya Mt., 450 m, around puddle, 14.vii.1972, leg. K. Gorodkov (ZMSP); 2 males 3 females, middle part of the River Mamontovaya, N Perkatkun, around puddle, 17.vii.1972, leg. K. Gorodkov (ZMSP); 24 males 17 females, Somnitel’naya Bay, south of Island, around puddle, 10.vii.1972, leg. K. Gorodkov (5 males 5 males SZMN, rest ZMSP); 2 males 3 females, slope of Tundrovii Mt., around puddle, 18.vii.1972, leg. K. Gorodkov (1 females SZMN, rest ZMSP).