Cheilosia ( Taeniochilosia ) aenigmatosa Barkalov, 1993

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 : 6-8

Cheilosia ( Taeniochilosia) aenigmatosa Barkalov, 1993 stat. rev.

Fig. 2

Cheilosia aenigmatosa Barkalov, 1993: 700 .

Cheilosia grisella Becker, 1894 – Stackelberg & Richter 1968: 246. — Peck 1988: 104. — Barkalov & Ståhls 1997: 28. — Gujabidze 2002: 245. — Mengual et al. 2020: 25. — Speight 2020a: 35.

Cheilosia aenigmatosa – Barkalov 1993: 700. — Barkalov & Ståhls 1997: 52. — Barkalov & Mutin 2018: 486.

Differential diagnosis

Cheilosia aenigmatosa is identified as belonging to the subgenus Taeniochilosia by the combination of bare eye, black legs and the anterior process of lunula not broadly confluent with the face ( Barkalov & Ståhls 1997). The male genitalia are figured in Barkalov (1993). The male of C. aenigmatosa is very similar to C. pollinifacies and can be distinguished as follows: posterior margin of scutellum with few and thin setae, diameter almost as thin as scattered black pile on disc of scutellum ( Fig. 2E) (in C. pollinifacies the posterior margin of scutellum has multiple setae with a diameter much larger than diameter of scattered long black pile on disc of scutellum; Fig. 56E), scutum with dense erect short golden pile, with sparse long black erect pile intermixed (in C. pollinifacies scutum also with sparse long black pile, but short pile on scutum semi-adpressed, variable in colour, ranging from predominantly black to predominantly golden). Females of C. aenigmatosa differ from C. pollinifacies by the absence of black setae or pile on posterior margin of scutellum, while black setae are present on posterior margin of scutellum in C. pollinifacies . Genetically, it is similar to C. ouwehandae Bot sp. nov., but the male differs in many ways (the female of C. ouwehandae remains unknown): C. aenigmatosa is larger (body size usually at least 8 mm instead of 6.5 mm), face and parafacia densely pruinose (slightly pruinose in C. ouwehandae ), facial tubercle less well developed, not further projecting than mouth edge (rounder, and further protruding, well beyond mouth edge in C. ouwehandae ), postpedicel black (basoventrally orange in C. ouwehandae ), frontal triangle with large proportion of yellow pile (pile black in C. ouwehandae ), pile on scutum golden instead of whitish, and posterior margin of scutellum with black pile setae instead of black setae and abdomen with less dense pruinosity.

Material examined

Collected in 2018, 2019 and 2021, but 2018 records were not published in Mengual et al. (2020). Thus, all records are reported here.

GEORGIA – Adjara Region • 1 ♀; Kintrishi Nature Reserve ; 41.7619° N, 42.1162° E; 2462 m a.s.l.; 16 Jun.–30 Jun. 2018; GGBC-members leg; ZFMK, ZFMK-TIS-8010536 • 1 ♀; Kintrishi Nature Reserve ; 41.7619° N, 42.1162° E; 2462 m a.s.l.; 30 Jun.–14 Jul. 2018; GGBC-members leg; ZFMK, ZFMK-TIS-8010398 • 1 ♀; Mtirala N.P.; 41.6535° N, 41.8730° E; 1106 m a.s.l.; 16 Jul. 2021; S. Bot leg.; BA, SB.003061 . – Imereti • 2 ♂♂; road from Abastumani to Sairme ; 41.824° N, 42.847° E; 2150 m a.s.l.; 10 Jun. 2019; F. Van de Meutter leg.; FMT • 1 ♂; Abastumani area , along path; 41.823° N, 42.840° E; 2025 m a.s.l.; 11 Jun. 2019; F. Van de Meutter leg.; FMT . – Mtskheta-Mtianeti • 1 ♂; Gudauri-pass ; 42.5336° N, 44.4751° E; 2210 m a.s.l.; 11 Jul. 2019; A. Ssymank leg.; ASW, Ssy 9504- 01, ZFMK-TIS-8009412 • 1 ♀; same data as for preceding; ASW, Ssy 9504-02, ZFMK-TIS-8009413 . – Samegrelo-Zemo Svaneti • 1 ♀; 43.0319° N, 42.8272° E; 1905 m a.s.l.; 13 Jun. 2019; X. Mengual leg; ZFMK, ZFMK-DIP-00066299 = ZFMK-TIS-8008764 • 1 ♂; 42.900° N, 42.934° E; 2700 m a.s.l.; 17 Jun. 2019; S. Bot leg.; SBA, SB.003064 • 1 ♀; 42.9140° N, 43.0911° E; 2575 m a.s.l.; 18 Jun. 2019; X. Mengual leg.; ZFMK, ZFMK-DIP-00066298 = ZFMK-TIS-8006837 • 1 ♂; 7 km W of Ushguli , near hilltop; 42.906° N, 42.937° E; 2615 m a.s.l.; 16 Jun. 2019; F. Van de Meutter leg.; FMT • 1 ♀; 7.5 km N of Mestia , path to glacier; 42.738° N, 43.113° E; 1800 m a.s.l.; 14 Jun. 2019; F. Van de Meutter leg.; FMT • 3 ♂♂; 43.0275° N, 42.9115° E; 2887 m a.s.l.; 14 Jul. 2021; S. Bot leg.; SBA, SB.003058 to SB.003060 • 2 ♀♀; same data as for preceding; SBA, SB.003056 , SB.003057 . – Samtskhe-Javakheti • 1 ♂; Borjomi N.P. ; 41.824° N, 42.848° E; 2165 m a.s.l.; 10 Jun. 2019; S. Bot leg.; SBA, SB.003062 • 1 ♀; same data as for preceding; SBA, SB.003063 .

RUSSIA – Kabardino-Balkaria • 1 ♀; 43.4841° N, 43.1006° E; 1776 m a.s.l.; 6 Jun. 2018; A. Przhiboro leg.; ZFMK, ZFMK-DIP-00078649 = ZFMK-TIS-8009592 • 2 ♂♂; 43.4795° N, 43.0971° E; 1836 m a.s.l.; 7–8 Jun. 2018; A. Przhiboro leg.; yellow plates; ZFMK, ZFMK-DIP-00078658 = ZFMKTIS-8009602 , ZFMK-DIP-00078660 = ZFMK-TIS-8009567 • 2 ♀♀; same data as for preceding; ZFMK, ZFMK-DIP-00078653 = ZFMK-TIS-8009596 ; ZFMK-DIP-00078659 = ZFMK-TIS-8009566; ZFMK .

Genetics

DNA barcodes of C. aenigmatosa were resolved into three clusters with high support (BS = 96.7–100%). DNA barcodes of European specimens of C. grisella were grouped together with high support (BS = 98.7%). See Remarks.

Remarks

Previous records of C. grisella from the Caucasus are referred here to as C. aenigmatosa and C. grisella is considered absent from the Caucasus Region.

Barkalov & Ståhls (1997) synonymized C. aenigmatosa with C. pollinifacies without providing an explanation or comment. Our genetic study resolved C. pollinifacies and related species in several clusters. One group corresponds to the original description of C. pollinifacies and three other groups match the description of C. aenigmatosa , with C. ouwehandae sp. nov. branching in between (Supp. file 1: Fig. S1). Although genetically similar, C. ouwehandae differs from C. aenigmatosa morphologically (see Differential diagnosis). Within C. aenigmatosa , we could not find morphological differences between the genetic clusters. Here we reinstate C. aenigmatosa as a genetically and morphologically different species from C. pollinifacies .

Biology

During our expeditions, collected between 6 June and 16 July at an altitude between 1106 and 2887 m a.s.l. Behaviour difficult to ascertain due to confusion with the very similar C. pollinifacies with which it often co-occurs. At places where C. aenigmatosa was caught, individuals belonging to C. aenigmatosa or C. pollinifacies were often found in clearings in forest, along forest edges or near tall vegetation in alpine meadows, visiting low flowers including Caltha palustris L. and Ranunculus sp.

Distribution

Caucasus ( Russia, Georgia).