Cheilosia ( Floccocheila ) illustrata portschinskiana Stackelberg, 1960

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 : 69-71

Cheilosia ( Floccocheila) illustrata portschinskiana Stackelberg, 1960

Fig. 35

Cheilosia portschinskiana Stackelberg, 1960: 441 .

Cheilosia oestracea (Linnaeus, 1761) [sic] var. b, c, d, e, f – Portschinsky 1877: 161.

Cheilosia oestracea (Linnaeus, 1758) – Radde 1899: 453.

Cheilosia portschinskiana – Stackelberg & Richter 1968: 248. — Stackelberg 1970: 61.

Cheilosia illustrata portschinskiana – Peck 1988: 105. — Barkalov 1993: 718. — Claussen 1998: 385; Barkalov & Mutin 2018: 485. — Mengual et al. 2020: 23.

Cheilosia portschinskiana Stackelberg, 1956 [sic] – Gujabidze 2002: 246.

Cheilosia oestracae (Linnaeus, 1758) [sic] – Gujabidze 2002: 246.

Differential diagnosis

Cheilosia illustrata portschinskiana is a very distinctive species, easily identified from other species of Cheilosia in the Caucasus by the combination of dense body pile, pilose eye, bare face, posterior margin of scutellum without setae and alternating pattern on body of black and pale (white and/or yellow and/or orange) pile bands ( Fig. 35A, C). Very similar to extralimital nominal C. illustrata , but face bare (almost always pilose in nominal C. illustrata ) and postpedicel regularly orange to some extent (usually black or dark brown in nominal C. illustrata , but much overlap). In some specimens in the Caucasus, all pile on tergum II black instead of whitish.

Material examined

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

Genetics

All DNA barcodes of C. illustrata illustrata from Europe and C. illustrata portschinskiana from the Caucasus cluster together with high support (BS = 100%). The single DNA barcode of Cheilosia motodomariensis Matsumura, 1916 from Russian Far East in our dataset is resolved embedded within the cluster of C. illustrata .

Remarks

This taxon was first described as a new species by Stackelberg (1960). It is very similar to C. illustrata (Harris, 1779) and therefore regarded as a subspecies of C. illustrata since Barkalov (1981). According to Barkalov (1993), C. illustrata portschinskiana is the only subspecies of C. illustrata occurring in the Caucasus. Our genetic research confirms the close relationship with C. illustrata and C. motodomariensis , since they are genetically indistinguishable (Supp. file 1: Fig. S1).

Biology

During our expeditions, collected between 18 June and 3 August at an altitude between 1476 and 2900 m a.s.l. as well as on herbaceous flowers as on flowering trees ( Sorbus sp. ).

Distribution

Caucasus ( Armenia, Georgia, Russia).