Cheilosia ( Cheilosia ) borjomi, Bot & Mengual & Meutter & Skevington, 2025

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 : 29-34

Cheilosia ( Cheilosia) borjomi sp. nov.

urn:lsid:zoobank.org:act:

Figs 13–14

Cheilosia variabilis ( Panzer, 1798) – Mengual et al. 2020: 21 (part, see Remarks).

Differential diagnosis

The combination of eye and face with pile and black legs of Cheilosia borjomi sp. nov. distinguish this new species from all other Cheilosia of the region, except for C. melanopa , C. redi and C. variabilis . Cheilosia borjomi is similar to C. melanopa and C. redi but larger (on average 11 mm vs 9 mm), with a more slender abdomen, legs all black (base and sometimes apex of tibiae yellow in C. melanopa and C. redi ), in the male the ventral part of the metafemur has black setae (with short black pile in C. melanopa and C. redi ) and in the female the metatibia has black pile anterolaterally (yellow in C. redi ) and scutum with shorter semi-adpressed yellow and black pile and with sparse, longer, more erect black pile ( Fig. 14B, with short erect yellow pile in C. melanopa ).

This new species is also very similar to C. variabilis , in the male no differences in genitalia could be detected. In general, C. borjomi sp. nov. has denser body pruinosity, reflected in pruinose occiput and pleura in the female (occiput and pleura shiny in C. variabilis ) and all pruinose scutum and scutellum in the male (in C. variabilis males the posterior part of scutum and scutellum have often shiny parts). Moreover, male differs in the pile on scutum and scutellum, with only long erect predominantly black pile in C. borjomi ( Fig. 14A) (in C. variabilis at least posterior half of scutum and scutellum with both long and short pile), procoxa with anterior part usually with at least some black setae on apical half ( Fig. 14C) (in most populations of C. variabilis , including those from the Caucasus, the male procoxa has yellow pile and setae only; although some populations of C. variabilis , for instance in the Pyrenees, males have sometimes a few black setae on the procoxa). Females of C. borjomi are best differentiated from C. variabilis females by pruinose pleura, although often only faintly so (in C. variabilis the ventral part of posterior anepisternum and dorsal part of katepisternum are brightly shiny, contrasting with pruinose nearby pleura), occiput often pruinose contrasting with adjacent shiny posterior part of the frons (in C. variabilis the occiput is shiny behind dorsal eye corner), pile on scutum variable, but often with dense semi-adpressed pile and sparse longer pile ( Fig. 14B) (in C. variabilis females there is only one type of short adpressed pile on scutum usually). The described differences in females are subject to some variation, making identification of some less typical individuals very difficult.

Etymology

The species is named after the town of Borjomi in the Lesser Caucasus, where most of the type series were collected in its vicinity. Species epithet to be treated as a noun in apposition.

Material examined

Holotype

GEORGIA • ♂; Imereti, road from Abastumani to Sairme ; 41.8385° N, 42.8194° E; 2260 m a.s.l.; 10 Jun. 2019; X. Mengual leg.; ZFMK, ZFMK-TIS-8006823 = ZFMK-DIP-00066260 .

Paratypes

ARMENIA – Kotayk Province • 1 ♀; Tsaghkadzor, Y.S.U. Rest House ; 40.533625° N, 44.703028° E; 1915 m a.s.l.; 23 May 2022; X. Mengual leg.; ZFMK, ZFMK-DIP-00093664 = ZFMK-TIS-8014603 . Syunik Province • 1 ♂; near Gorayk, Spandarian Reservoir ; 39.684513° N, 45.777478° E; 2078 m a.s.l.; 19 May 2022; X. Mengual leg.; ZFMK, ZFMK-DIP-00093268 = ZFMK-TIS-8014605 . – Vayots Dzor Province • 1 ♂; W of Saravan ; 39.718437° N, 45.63076° E; 1590 m a.s.l.; 19 May 2022; X. Mengual leg.; ZFMK, ZFMK-DIP-00093416 = ZFMK-TIS-8014601 .

GEORGIA – Imereti • 15 ♂♂; same data as for holotype; ZFMK, ZFMK-DIP-00066253 , ZFMKDIP-00066254 = ZFMK-TIS-8006821 , ZFMK-DIP-00066255 , ZFMK-DIP-00066256 , ZFMKDIP-00066258 , ZFMK-DIP-00066259 , ZFMK-DIP-00066261 to ZFMK-DIP-00066270 • 1 ♀; same data as for holotype; ZFMK, ZFMK-DIP-00066272 • 3 ♂♂; same data as for holotype; J. van Steenis leg.; JSB, 2019-00.844–2019-00.846 • 3 ♀♀; same data as for holotype; J. van Steenis leg.; JSB, 2019-00.847 to 2019-00.849 • 8 ♂♂; road from Abastumani to Sairme ; 41.8245° N, 42.8482° E; 2165 m a.s.l.; 10 Jun. 2019; J.H. Skevington leg.; CNC, CNC1386126 , CNC1386130 , CNC1386131 , CNC1386134 , CNC1386137 , CNC1386141 , CNC1386144 , CNC1386147 • 1 ♀; road from Abastumani to Sairme ; 41.86433° N, 42,77842° E; 1830 m a.s.l.; 10 Jun. 2019; X. Mengual leg.; ZFMK, ZFMKDIP-00066271 = ZFMK-TIS-8006824 • 1 ♀; Abastumani, road Abastumani to Sairme ; 41.8242° N, 42.8472° E; 2150 m a.s.l.; 10 Jun. 2019; F. Van de Meutter leg.; FMT . – Kakheti • 1 ♀; Dedoplis Tskaro ; 41.488° N, 46.094° E; 780 m a.s.l.; 30 Apr. 2023; S. Bot leg.; SBA, SB.003078 = ZFMKTIS-8027997 • 1 ♀; Dedoplis Tskaro ; 41.4856° N, 46.0947° E; 750 m a.s.l.; 30 Apr. 2023; F. Van de Meutter leg.; FMT • 7 ♂♂; Lagodekhi N.P.; 41.8767° N, 46.2429° E; 615 m a.s.l.; 2 May 2023; S. Bot leg.; SBA, SB.003079 = ZFMK-TIS-8028004 , SB.003080 = ZFMK-TIS-8028005 , SB.003081 to SB.003085 • 2 ♂♂, 1 ♀; Lagodekhi N.P. ; 41.8777° N, 46.2436° E; 625 m a.s.l.; 2 May 2023; F. Van de Meutter leg.; FMT • 7 ♂♂; Lagodekhi N.P. ; 41.8747° N, 46.2415° E; 600 m a.s.l.; 2 May 2023; W. Opdekamp leg.; WOR, E009 , E010 , E022 , E023 , E025 , E029 , E030 • 1 ♂; Zemo Mskhaigori ; 41.88° N, 46.1969° E; 530 m a.s.l.; 11 May 2023; F. Van de Meutter leg.; FMT . – Mtskheta-Mtianeti • 1 ♂; Tbilisi N.P. ; 41.877° N, 45.0138° E; 1250 m a.s.l.; 4 May 2023; F. Van de Meutter leg.; FMT • 1 ♂; Lutkhubi ; 42.3930° N, 44.7929° E; 1734 m a.s.l.; 8 May 2023; W. Opdekamp leg.; WOR, C005 . – Racha-Lechkhumi and Kvemo Svaneti • 1 ♂; near Shovi ; 42.713° N, 43.701° E; 2022 m a.s.l.; 7 Jul. 2021; S. Bot leg.; SBA, SB.003077 . – Samegrelo-Zemo Svaneti • 1 ♂; Ushguli ; 42.950° N, 43.075° E; 2275 m a.s.l.; 24 Jun. 2018; S. Bot leg.; SBA, SB.003074 • 1 ♀; 42.897° N, 43.008° E; 2630 m a.s.l.; 28 Jun. 2018; S. Bot leg.; SBA, SB.003075 • 1 ♂; 42.9471° N, 43.0671° E; 2257 m a.s.l.; 15 Jun. 2019; J.H. Skevington leg.; CNC, CNC1386512 • 1 ♂; 42.948° N, 43.070° E; 2258 m a.s.l.; 15 Jun. 2019; L. Hofstee leg.; LHH . – Samtskhe-Javakheti • 4 ♂♂; Borjomi N.P. ; 41.867° N, 43.251° E; 2000 m a.s.l.; 18 Jun. 2018; S. Bot leg.; SBA, SB.003065 to SB.003068 • 1 ♀; Borjomi N.P. ; 41.857° N, 43.208° E; 1900 m a.s.l.; 18 Jun. 2018; S. Bot leg.; SBA, SB.003069 • 1 ♂; Borjomi N.P. ; 41.846° N, 43.145° E; 1800 m a.s.l.; 19 Jun. 2018; S. Bot leg.; SBA, SB.003072 • 1 ♂; same data as for preceding; XLS, SB.003251 • 1 ♀; same data as for preceding; SBA, SB.003073 = CNC databasing S. Bot 936 • 1 ♂; Borjomi N.P. ; 41.810° N, 43.119° E; 2050 m a.s.l.; 19 Jun. 2018; S. Bot leg.; SBA, SB.003070 • 1 ♀; same data as for preceding; SBA, SB.003071 • 1 ♂; Abastumani area ; 41.82344° N, 42,84° E; 2025 m a.s.l.; 11 Jun. 2019; X. Mengual leg.; ZFMK, ZFMK-DIP-00066268 • 3 ♀♀; same data as for preceding; ZFMK, ZFMK-DIP-00066273 = ZFMK-TIS-8006825 , ZFMK-DIP-00066274 , ZFMKDIP-00066281 = ZFMK-TIS-8006820 • 1 ♀; Borjomi N.P. ; 41.79° N, 42.82° E; 1515 m a.s.l.; 11 Jun. 2019; J. van Steenis leg.; JSB, 2019-00.857 • 2 ♀♀; Borjomi N.P. ; 41.82° N, 42.84° E; 2100 m a.s.l.; 11 Jun. 2019; J. van Steenis leg.; JSB, 2019-00.853 , 2019-00.881 • 1 ♀; Borjomi N.P. ; 41.8210° N, 42.8340° E; 1992 m a.s.l.; 11 Jun. 2019; S. Bot leg.; SBA, SB.003076 • 2 ♂♂; Borjomi N.P. ; 41.8697° N, 42.7923° E; 1683 m a.s.l.; 11 Jun. 2019; J.H. Skevington leg.; CNC, CNC1386342 , CNC1386362 • 2 ♀♀; Borjomi N.P. ; 41.8181° N, 42.8316° E; 2004 m a.s.l.; 11 Jun. 2019; J.H. Skevington leg.; CNC, CNC1386249 , CNC1386287 • 1 ♀; Sakire ; 41.7301° N, 43.3306° E; 1820 m a.s.l.; 10 May 2023; F. Van de Meutter leg.; FMT .

Description

Male

LENGTH. Body 10–12 mm, wing 10–11 mm.

HEAD. Face black, with facial tubercle, with long mixed black and white pile, bare around facial tubercle; slightly pruinose, except more densely pruinose below lunule and facial tubercle bare. Parafacia black, about just over half to two-third as wide as postpedicel, pruinose, white pilose. Frontal triangle black, slightly swollen, pruinose, long black pilose, with medial frontal sulcus. Length of eye contiguity about as long as or slightly longer than the length of frons. Angle of approximation of eyes ca 90°. Vertex pruinose, long black pilose. Occiput pruinose, short yellow pilose, on dorsal margin with long black pile. Lunule dark orange to blackish, with distinct medial arm, separating acetabula. Scape and pedicel black with black setae; postpedicel rounded, about as high as wide, black, pruinose; arista black, black pilose, pile about as long as basal diameter of arista. Eye with dense yellow pile.

THORAX. Scutum black, pruinose, finely punctured, with erect long black and yellow pile. Scutellum black, pruinose, with erect long black and yellow pile, posterior margin with black setae, length of setae about as long as length of scutellum. Pleura black, pruinose, with yellow pile except posterior anepisternum, anepimeron and sometimes ventral part of katepisternum with black pile intermixed; katepisternum continuously pilose. Haltere pedicellum yellow or dark yellow, capitulum dark brown or black.

WING. Wing including alula entirely microtrichose, with brown tinge, especially in anterior half. Veins black. Stigma brown.

LEGS. Black. Pruinose. Procoxa with yellow pile, on anterior part with black setae on apical half. Profemur with long black posteroventral pile, mesofemur with long mixed black and yellow posteroventral pile, metafemur anteriorly and posteriorly with long white pile, ventrally with black setae. Metatibia anteriorly with black pile, posteriorly at least apical half with yellow pile.

ABDOMEN. Terga I–IV laterally with long erect pile, medially pile shorter and semi-adpressed; tergum I with white pile; pile on terga II and III yellow except posteriorly in center, black pile more extensive on tergum III; anterolateral corners of tergum IV with yellow pile, remainder with black pile; terga I–IV pruinose, medially most dense. Sterna I–IV densely pruinose, laterally with long erect pile, in center pile shorter and adpressed, pile on sterna I–IV yellow except few black adpressed pile along posterior margin of sternum IV and sometimes sternum III. Genitalia with surstylus about 1.3 times as long as wide ( Fig. 14E); postgonite very long and narrow, sickle-shaped ( Fig. 14D).

Female

LENGTH. Body 9.5–13 mm, wing 10–11.5 mm.

Similar to the male, except for normal sexual dimorphism and the following characters. Face with entirely yellow pile. Frons with short yellow pile, with longer black pile intermixed. Scutum shiny except lateral margins widely slightly pruinose, with shorter semi-adpressed yellow and black pile and with sparse longer more erect black pile. Scutellum shiny, with pile of two lengths, variable black or yellow short pile and long black pile. Pleura with yellow pile. Procoxa usually with yellow pile and setae only. Femora with predominantly yellow pile, sometimes with a few black setae on ventral side on metafemur. Pile on terga shorter and black pile more extensive. Pile on sterna shorter, without black pile.

Morphological variation

One female (ZFMK-DIP-00093664 = ZFMK-TIS-8014603) is markedly different by having much less black pile in general, all pale pile very bright golden yellow instead of whitish, and tibiae yellow at both ends instead of tibiae black.

Genetics

All DNA barcodes of C. borjomi sp. nov. are resolved into one cluster without high support (BS <90%).

Remarks

Some records of C. variabilis in Mengual et al. (2020) actually represents C. borjomi sp. nov., and are reported here again as C. borjomi .

Biology

Collected between 530–2260 m a.s.l. on extensive grasslands and in or near forest, where it feeds on low flowers. This species can be found in sympatry with C. variabilis in Borjomi National Park.

Distribution

So far only known from the Lesser and Greater Caucasus in Armenia and Georgia. Mainly recorded in the Lesser Caucasus, with only a very few records from the Greater Caucasus.