Cheilosia Meigen 1822
Creators: name: Barkalov, Anatolij V.
name: Ståhls, Gunilla
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Syrphidae
Cheilosia

description: Key to subgenera of Cheilosia occurring in Nepal
The subgeneric key works for specimens of the male sex, and for females except for the last couplet of the key.
1. Antennal pits confluent (meaning that the medial process of lunule is narrowed (pointed) anteriorly, and not connected with the face and the antennal pits are thus connected, sometimes seemingly connected and close inspection using higher magnification is necessary) ....................................... 2
– Antennal pits separated (medial process of lunule anteriorly broader and clearly merged with the face (Fig. 2D) ........................................................................................................................................... 4
2. Eye bare ............................................................................................................................................ 3
– Eye pilose ........................................................................... Taeniochilosia Oldenberg, 1916 (in part)
3. Length of black pile on scutellum margin shorter than length of scutellum (this character is variable in species from Europe and Central Asia); right process of superior lobe of hypandrium short (extended only in distal direction) and broad (Fig. 43F) ..................................................................................... ............................................................................................ Taeniochilosia Oldenberg, 1916 (in part)
– Length of black bristles on scutellum margin as long as or longer than length of scutellum; right process of superior lobe of hypandrium long and narrow, curved in distal part (Fig. 54G, I) ........... .......................................................................................................... Eucartosyrphus Barkalov, 2002
4. Tergites orange with black stripes along hind margins (Fig. 14C), superior lobe of hypandrium with four projections (Fig. 17F) ..................................................................... Rubrocheila Barkalov, 2002
– Tergites black or dark-brown, if with pale maculae, then superior lobe of hypandrium with other structure ............................................................................................................................................ 5
5. Arista plumose (Fig. 32A) ........................................................................ Endoiasimyia Bigot, 1882
– Arista bare or with shorter pilosity ................................................................................................... 6
6. Wings with distinct brown spot medially (Figs 30A, 32C). Big flies, resembling small bumblebees (Fig. 12). Left process of superior lobe of hypandrium shifted to the middle (Fig. 29G) .................. ............................................................................................................... Floccocheila Barkalov, 2002
– Wings without brown spot medially, or, if with large black spots on wings, then left process of superior lobe of hypandrium different ............................................................................................................ 7
7. Surstylus broad to strikingly broad basally, and cercus enlarged (in size almost comparable with size of surstylus Fig. 57E), superior lobes of hypandrium asymmetric ...... Pollinocheila Barkalov, 2002
– Surstylus not very broad basally and cercus distinctly smaller than surstylus (e.g., Fig. 56H), superior lobes of hypandrium symmetric or asymmetric ............................................................................... 8
8. Distiphallus (apical sclerite of aedeagus) without lobes (projections) anteriorly, with big lobes posteriorly (Fig. 68G); frons broad, at level of antenna the frons is at least as broad as or much broader than the width of one eye ......................................................... Neocheilosia Barkalov, 1983
– Distiphallus with lobes (projections) anteriorly, frons narrower than width of eye ......................... 9
9. Distiphallus with broad and large anterior lobes, without posterior lobes (e.g., Figs 20G, 27H) ...... ....................................................................................................................... Cheilosia Meigen, 1822
– Distiphallus with two pairs of lobes – anterior and posterior (e.g., Figs 2E, 18D, 24C, 50E) ........... ........................................................................................................... Montanocheila Barkalov, 2002
Key to Nepalese species of Cheilosia
1. Eye bare (slender, black, short pilose species, antennal pits confluent) (Figs 54–55) ........................ .......................................................................................... C. (Eucartosyrphus) procera sp. nov. ♂ ♀
– Eye pilose, entirely or partly (sometimes pile very short and visible only under high magnification) ........................................................................................................................................................... 2
2. Face in ventral and/or dorsal part with distinct pile (pilosity of parafacia or gena not considered) (Figs 13A, 24A, 25A, D, 31A) ......................................................................................................... 3
– Face without distinct pile (Figs 5A, 18A, 43A) .............................................................................. 16
3. Arista plumose (Fig. 31B) ......................................... C. (Endoiasimyia) indiana (Bigot, 1883) ♂ ♀
– Arista bare, or with short or long pilosity (e.g., Figs 5B, 57B) ........................................................ 4
4. Abdomen with distinct grey pollinose maculae antero-laterally on tergites I–III, pollinosity forming a grey band on tergite IV, scutum medially densely grey pollinose (Fig. 40) .................................... .............................................................................................................. C. (C.) maculata sp. nov. ♂ ♀
– Not this combination of characters (abdomen without distinct grey pollinose maculae, scutum not densely grey pollinose medially) ...................................................................................................... 5
5. Body robust, with long, dense, pale pilosity, (small) bee-mimic (Fig. 26) ....... C. (M.) gilva sp. nov.
– Body slender (Fig. 53D), pilosity not so long and bright, not bee-like ............................................ 6
6. Body black, face with only some pile dorso-laterally near parafacia, basoflagellomere orange, scutum black pilose (Fig. 68) .......................................................................................................................... .. C. (Neocheilosia) komabaensis Shiraki, 1968 [males of C. flavigena sp. nov. could key out here]
– Not with this combination of characters ........................................................................................... 7
7. Holoptic (♂♂) (Fig. 2C) ................................................................................................................... 8
– Dichoptic (♀♀) (Fig. 2D) ............................................................................................................... 12
8. Face with only few long pile on ventral part, face densely pollinose (Fig. 57A) ............................... .......................................................................................................................... C. (P.) rava sp. nov. ♂
– Face more extensively pilose, or with patch of pilosity near dorsal part of parafacia (Figs 13A, 24A, 25A, D, 31A) .................................................................................................................................... 9
9. Femora dark-brown or black in basal ⅓ and yellow in apical ⅔, body pollinose but shiny with distinct golden-green reflections (Fig. 53D) ..................................... C. (P.) quinta Barkalov & Cheng, 2004
– Not this combination of characters ................................................................................................. 10
10. Katepisternum with dorsal and ventral pile patches connected, parafacia with some pile longer than eye pilosity (Fig. 25A, D) ................................................................................. C. (M.) gilva sp. nov.
– Katepisternum with dorsal and ventral pile patches widely separated, parafacia with shorter pilosity .............................................................................................................................................11
11. Femora black with yellow tips; eye partly pilose; superior lobe of hypandrium with sharply pointed left process (Figs 13, 14A) .......................................................... C. (C.) difficilis Hervé-Bazin, 1929
– Femora yellow in apical ½–⅓, and black in basal part; eye entirely pilose; superior lobe of hypandrium with different shape of left process (Figs 48–49) ............................................... C. (C.) pica sp. nov.
12. Frons with a (narrow) transversal stripe of grey pollinosity (Figs 22B, 25A, 56B, 65A) .............. 13
– Frons without transversal stripe of grey pollinosity (e.g., Figs 58C, 62B) ..................................... 15
13. Scutum antero-medially with two longitudinal stripes of grey pollinosity, pilosity semi-erect and of equal length. Eye with very short pilosity, only visible under high magnification (Figs 22, 23A–B) ......................................................................................................................................................... 14
– Scutum antero-medially without longitudinal stripes of grey pollinosity, pilosity erect and of different lengths, comparatively long and with 2–3× shorter pile on posterior half. Eye with longer pilosity, visible under low magnification (Figs 25–26) .................................................. C. (M.) gilva sp. nov.
14. Scutum short black pilose, lunule clear yellow, anepisternum yellow pilose, face with small pile patch restricted to dorsal part at parafacia (Figs 22, 23A) .......................................... C. flavigena sp. nov.
– Scutum yellow pilose, anepisternum yellow pilose and postero-dorsally with some black pile, face with pile on ventral part (Figs 64C–E, 65) ............................................................... C. versa sp. nov.
15. Femora blackish in basal ⅓, apical ⅔ yellow. (Figs 48–49) ............................... C. (C.) pica sp. nov.
– Femora black, apical ⅙ of tips yellow (Fig. 14A) ...................... C. (C.) difficilis Hervé-Bazin, 1929
16. Fore coxa with a distinct, lateral spur (Fig. 61D) ........................................................................... 17
– Fore coxa without lateral spur ........................................................................................................ 19
17. Face protruded, with characteristic shape in lateral view, in anterior view face narrow (Figs 20A, 21B) ................................................................................................................ C. (C.) falcata sp. nov.
– Face not protruded .......................................................................................................................... 18
18. Scutum with short adpressed and 3–5× longer erect black pilosity (Fig. 59B, D) ............................. ........................................................................................................................ C. (C.) spinosa sp. nov.
– Scutum with erect yellow pilosity of approximately equal length (Fig. 61A–B) ............................... .......................................................................................................................... C. (C.) spuria sp. nov.
19. Tergites I–IV yellow in colour, with black transversal bands at posterior margins (width of bands ⅓ or ¼ of tergite length) (Fig. 14C) ....................................... C. (R.) egregia Barkalov & Cheng, 1998
– Tergites I–IV black or brown, with more or less developed grey pollinosity ................................. 20
20. Scutellum hind margin without distinct strong black bristles, with dense long, black or yellow pilosity ............................................................................................................................................ 21
– Scutellum hind margin with at least two distinctly stronger black bristles (stronger than surrounding pilosity), or with multiple long and somewhat stronger bristles than surrounding pilosity ........... 40
21. Eye with black (or dark-brown) pilosity ......................................................................................... 22
– Eye with yellow or with brown pilosity (use high magnification and good illumination) ............. 32
22. Face distinctly produced antero-ventrally (Fig. 12A–D) ....................... C. (F.) crassata sp. nov. ♂ ♀
– Face less or not protruded antero-ventrally (Fig. 18A) .................................................................. 23
23. Basoflagellomere orange-yellow or brownish-orange, dorsal margin often darkened ................... 24
– Basoflagellomere dark-brown or black, sometimes densely brown pollinose, with or without reddishbrown postero-ventral corner .......................................................................................................... 26
24. Parafacia non-pollinose along margin near face, while densely grey pollinose near eye .................. ........................................................... C. (M.) erratica Barkalov & Peck, 1997 (see also couplet 35)
– Parafacia entirely pollinose or almost so ........................................................................................ 25
25. Scutellum hind margin and postalar calli with yellow pilosity (Fig. 4) ............................................. .............................................................................................................. C. (M.) albipicta sp. nov. ♂ ♀
– Scutellum hind margin and postalar calli with black pilosity (Fig. 6A) ............................................. ....................................................................... C. (M.) alpha sp. nov. ♂ (see also couplets 39 and 49)
26. Tergites III–V only black pilose, clearly contrasting with pale pilosity of tergite II (Fig. 36) ........... .......................................................................................................... C. (F.) leucozonoides sp. nov. ♀
– Tergites III–V with mostly yellow or orange pilosity, sometimes also with patches of black pile of variable sizes laterally on tergites ................................................................................................... 27
27. Legs completely black .................................................................................................................... 28
– Legs at least with brownish or yellow basal ⅓ of tibia .................................................................. 29
28. Legs and pleura with only black pilosity (Fig. 10A–B) ................ C. (M.) brevimontana sp. nov. ♀
– Legs with some yellow pile on tarsi, hind femur, ventral part of anepisternum and katepisternum with patches of light pile (Fig. 46C–D) .......................................................... C. (M.) pernigra sp. nov. ♀
29. Tergite I with yellow pilosity laterally .... C. (F.) illustratoides sp. nov. (in part, see also couplet 39)
– Tergite I with black pilosity antero-laterally ................................................................................... 30
30. Sternites completely black pilose, superior lobe of hypandrium without left process (Fig. 45F) ...... .................................................................................................................... C. (M.) nigella sp. nov. ♂
– Sternites with mixed black and yellowish pilosity, superior lobe of hypandrium with left process (Fig. 33E) ........................................................................................................................................ 31
31. Face densely grey pollinose, except narrow shiny stripe in lower part (Fig. 63A); superior lobe of hypandrium as on Fig. 63D .......................................................................... C. (F.) vellea sp. nov. ♂
– Face shiny with narrow stripe of grey pollinosity in mid part (Fig. 33A); superior lobe of hypandrium as on Fig. 33E ........................................................................................... C. (F.) indistincta sp. nov.
32. Pleura with only whitish or yellowish pilosity ............................................................................... 33
– At least posterior part of anepisternum postero-dorsally also with some black pile ...................... 37
33. Tergites entirely yellow or white pilose .......................................................................................... 34
– Tergites II, III or IV yellow pilose with small patches of black pile on antero-lateral corners, or, yellow pilose and tergite III with transversal stripe of black pile ............................................................... 36
34. Parafacia very broad, in broadest part nearly as broad as basoflagellomere width, katepisternum with dorsal and ventral pile patches broadly separated .................................... C. (C.) pilivena sp. nov. ♀
– Parafacia narrower, about ⅔ of basoflagellomere width, katepisternum with dorsal and ventral pile patches connected ........................................................................................................................... 35
35. Hind femur apically with black and yellow pile ................. C. (M.) erratica Barkalov & Peck, 1997
– Hind femur apically with only yellow pilosity (Fig. 16B–C) ............................................................. ..................................................................................... C. (M.) distincta Barkalov & Cheng, 1998 ♀
36. Tergites III & IV with very small patches of black pile antero-laterally ........... C. (F.) collis sp. nov.
– Only tergite III with transversal band of black pile (Fig.16B) ........................................................... ....................... C. (M.) distincta Barkalov & Cheng, 1998 ♂ (but see discussion under C. distincta)
37. Katepisternum with dorsal and ventral pile patches separated, tergites III–IV only with whitish or pale yellowish pilosity .............................................................................. C. (C.) pilivena sp. nov. ♂
– Katepisternum with dorsal and ventral pile patches connected (sometimes only narrowly connected), tergites III–IV with yellowish, orange and/or black pilosity .......................................................... 38
38. Tergite IV black pilose on posterior ⅔ of tergite ............................................................................ 39
– Tergite IV entirely whitish or yellowish pilose, sometimes also with some black pile .................. 40
39. Hind femur with dense pale ventral and antero-ventral pilosity longer than femur width (Fig. 51B, D) ............................................................................................................... C. (M.) picta sp. nov. ♂ ♀
– Hind femur only with some scattered pale pile longer than femur width (Fig. 6B, D) ...................... ............................................................................ C. (M.) alpha sp. nov. ♂ (see also couplets 25, 49)
40. Scutum broadly black pilose between wing bases (Fig. 30A–B) ..... C. (F.) illustratoides sp. nov. ♂
– Scutum with patchy black and yellow pilosity (Fig. 4) .............................. C. (M.) albipicta sp. nov.
41. Body yellowish-brown; with dark-brown colour of parafacia, lateral stripes on frons, irregular fascia on femora, tibiae and tergites I–III dark-brown to black (Fig. 32C–D) ........... C. insolita sp. nov. ♀
– Body black, with more or less yellow legs ..................................................................................... 42
42. Scutum and abdomen with bright green reflections, tibiae and metatarsi mostly yellow (Fig. 38) ... ..................................................................................................... C. lucida Barkalov & Cheng, 1998
– Scutum and abdomen not with bright green reflections, tibiae and/or metatarsi largely black ...... 43
43. Antennae dark-brown to black, basoflagellomere often densely grey pollinose ............................ 44
– At least basoflagellomere partly yellow or reddish in colour ......................................................... 45
44. Male: posterior margin of tergite IV with black (or dark-brown) semi-erect or appressed pile in addition to semi-erect yellow pile. Female: fore coxa yellow (Fig. 67) ............................................. ................................................................................................................ C. (C.) weiperti sp. nov. ♂ ♀
– Male: posterior margin of tergite IV with yellowish semi-erect or appressed pile. Female: fore coxa brown .............................................................................. C. (C.) suspecta Barkalov & Cheng, 2004
45. Male: apices of femora yellow on anterior area, yellow part about ⅓–½ in anterior area but narrower in posterior part of femora. Female: femora completely yellow (Fig. 28) ......................................... ................................................................................................................. C. (C.) hauseri sp. nov. ♂ ♀
– Femora black or dark-brown, or with narrowly yellow tips ........................................................... 46
46. Face, parafacia, frons and pleurae heavily grey pollinose (Fig. 53E–G), with pollinosity obscuring the black integument ....................................................................................................................... 47
– Some of named parts non-pollinose and shiny, or sparsely pollinose ............................................ 48
47. All tibiae black ................................................................................................. C. (P.) rava sp. nov. ♂
– Tibiae yellow with more or less developed black ring (Fig. 44A–D) ................................................ ............................................................................................................ C. (T.) nepalensis sp. nov. ♂ ♀
48. Face distinctly protruded in lower part, basoflagellomere orange-brown or brown (Figs 7A, 8B) ... ................................................................................................................... C. (C.) angusta sp. nov. ♂
– Face not protruded in lower part, basoflagellomere bright orange in postero-ventral part and black in antero-dorsal part, or basoflagellomere orange .............................................................................. 49
49. Moderately sized species: body length 7–9.5 mm. Parafacia at least in dorsal half densely grey pollinose (Fig. 5A); frons of female with transversal stripe of grey pollinosity (Fig. 5D) ................ ............................................................................ C. (M.) alpha sp. nov. ♂ (see also couplets 25, 39)
– Small sized species: body length about 5 mm. Parafacia non-pollinose, shiny (Fig. 41A); frons of female without transversal stripe of grey pollinosity (Fig. 41D) ...... C. (M.) minuscula sp. nov. ♂ ♀
description: Published as part of Barkalov, Anatolij V. & Ståhls, Gunilla, 2022, Cheilosia (Diptera, Syrphidae: Rhingiini) of Nepal with descriptions of 29 new species, pp. 1-127 in European Journal of Taxonomy 829 (1) on pages 8-14, DOI: 10.5852/ejt.2022.829.1863, http://zenodo.org/record/6839936