Cheilosia ( Cheilosia ) albitarsis ( Meigen, 1822 )

Bot, Sander, Mengual, Ximo, Meutter, Frank Van de & Skevington, Jeffrey H., 2025, Review of the genus Cheilosia Meigen, 1822 (Diptera: Syrphidae) from the Caucasus, with the description of 14 new species, European Journal of Taxonomy 1023, pp. 1-181 : 12-14

Cheilosia ( Cheilosia) albitarsis ( Meigen, 1822)

Fig. 5

Syrphus albitarsis Meigen, 1822: 290 .

Cheilosia albitarsis – Stackelberg & Richter 1968: 245. — Stackelberg 1970: 61. — Peck 1988: 96. — Barkalov 1993: 708. — Gujabidze 2002: 246. — Mengual et al. 2020: 14.

Differential diagnosis

Cheilosia albitarsis is relatively easily to identify: the male stands out, together with the extralimital C. ranunculi Doczkal, 2000 , in having the proleg black, except tarsomeres 2–4 which are yellow ( Fig. 5A). In other species of Cheilosia the proleg is either entirely black, or the yellow parts are at least also present on the tibia. In the female this character is sometimes less clear and the central tarsomeres can be quite dark, but still distinguishable by the combination of a bare eye (pilose in the male), lunule with distinct medial arm separating acetabula (excluding the subgenus Taeniochilosia in which lunule lacks a medial arm and the acetabula are joined forming an antennal fossa) and yellow base of the wing. For differences with C. ranunculi , including drawings of the male genitalia, see Doczkal (2000).

Material examined

Collected in 2018, 2019, 2021, 2022 and 2023; see Mengual et al. (2020) for detailed records from 2018.

Genetics

All DNA barcodes of C. albitarsis are resolved into a cluster with high support (BS = 100%).

Biology

During our expeditions, collected between 8 May and 12 July at an altitude between 1210 and 2327 m. As is usual for the species, encountered feeding on Caltha palustris or (most often) on Ranunculus sp.

Distribution

Holarctic, within the Caucasus, known from Armenia, Azerbaijan, Georgia and Russia.