Cheilosia caerulescens calculosa Skufjin

Stahls, Gunilla & Barkalov, Anatolij V., 2017, Taxonomic review of the Palaearctic species of the Cheilosiacaerulescens-group (Diptera, Syrphidae), ZooKeys 662, pp. 137-171 : 145-146

Cheilosia caerulescens calculosa Skufjin Fig. 5

Cheilosia caerulescens calculosa Skufjin, 1977:57.

Type locality.

'Lipetzk Region, Galichia Gora reserve’ (Russia).

Type material studied.

Holotype, ♂, in ZIN. The holotype is labelled: 'Lipetzkaya obl. Galichia gora 18.V.1963 Skufjin’.

Description.

♂: Face in frontal view slightly divergent from level of antennal insertion to lower mouth edge, slightly elongated, shining with stripe of pollinosity. Facial knob moderate, shining (Fig. 5A). Parafacia shining with slight pollinosity, moderate in width, in broadest part about 2/3 of the width of basoflagellomere. Frons very slightly swollen, shining, with white and posteriorly some black pile. Frontal angle slightly <90°. Lunula dark-brown. Antennal pits separated. Vertical triangle with black pile. Eye-contiguity approximately equal to length of frons without lunula. Basoflagellomere oval, yellow, arista brownish, almost bare, with very short pile (Fig. 5B). Scutum black, shining with fine punctuation, covered with dense erect bright yellow pile of equal length, with black pile of same length intermixed. Postalar callus with black bristles. Scutellum hind margin with some long fine yellow and black pile. Pleurae with rather dense gray pollinosity and yellow waving on the end pile. Dorsal and ventral hair patch of katepisternum connected. Femora black with yellow extreme tips; mesofemur with long yellow pile on posterior surface of basal 4/5 and black pile of apical 1/5. Pile on anterior surface of metafemur long and yellow in basal 2/3 and short and depressed in apical 1/3. Tibiae yellow with black ring, tarsi yellow with black fifth segment. Halter yellow. Wing completely covered with microtrichia, with brown spot on cross-veins. R4 + 5 of wing not distinctly curved. Abdomen oval, shining black covered with erect yellow pile. Sternite I and IV with pollinosity, sternites II–III shining. Genitalia as in Fig. 5 E–G.

Female: Face as in male, parafacia shining, narrow, about 1/3 of width of basoflagellomere. Frons comparatively broad with two furrows (Fig. 5D). Vertical triangle with black pile. Basoflagellomere slightly broader than in male (Fig. 5C). Pilosity of scutum and scutellum as in male, but all bristles on scutellum hind margin yellow. Mesofemur with long yellow pile on posterior surface. Tibiae yellow with rather narrow black ring. Tarsi yellow with darkened 5th segment. Wing and abdomen as in male.

Size. Body length 9-10.2 mm.

Additional material studied.

Russia 4 ♂, 2 ♀ 'Lipetzk Region, Galichia Gora reserve, 24-28.IV.1966, Kuznetzova’ [VSU]; 1 female 'Lipetzk Region, Galichia Gora reserve, 12.5.1974, V. Kuznetsova’ [ZIN]; 1♂, 1 ♀ same place 24-25.IV.1966, (V. Kuznetzova) [ISEA].

Distribution.

European part of Russia.

Remark.

We treat the taxon as subspecies until evidence to the contrary is presented.