Cheilosia minuscula, Barkalov & Ståhls, 2022

Barkalov, Anatolij V. & Ståhls, Gunilla, 2022, Cheilosia (Diptera, Syrphidae: Rhingiini) of Nepal with descriptions of 29 new species, European Journal of Taxonomy 829 (1), pp. 1-127 : 74-77

Cheilosia minuscula sp. nov.

urn:lsid:zoobank.org:act:FD198E8B-9439-40E6-A0AA-14562DC63CCB

Figs 41–42

Differential diagnosis

Cheilosia (Montanocheila) minuscula sp. nov. has a similar structure of the male genitalia as the other members of the subgenus Montanocheila , but differs strikingly in it’s small size and narrow body. From all members of the genus C. minuscula sp. nov. differs by following characters: small size, eye pilose, face non-pilose, antennal pits separated, scutellum without bristles, male genitalia with gonopod (superior lobes) lacking a left process and with a well-developed right process. Cheilosia minuscula sp. nov. is here tentatively placed in the subgenus Montanocheila .

Etymology

The specific epithet is from the Latin ‘ minuscula ’ meaning ‘small’, and refers to the small size if the species.

Material examined

Holotype NEPAL • ♀; Solukhumbu Junbesi to Ringmo; 27°34′ N, 86°35′ E; 2700–3000 m a.s.l.; 12 May [19]97; Hauser leg. [515]; CSCA.

Paratypes NEPAL • 1 ♂ (specimen broken, head, abdomen and legs glued onto locality label); same data as for holotype; CSCA • 1 ♀; Solukhumbu, Sanam ; 27°27′ N, 86°53′ E; 2700–2800 m a.s.l.; 23 May 1997; Hauser leg. [532]; CSCA .

Description

Male

LENGTH. Body 5.2 mm, wing 4.5 mm.

HEAD. Face very broad, slightly widened ventrally, shiny black with slight grey pollinosity laterally and also with patches of microtrichia/pollinosity, no distinct pilosity, facial tubercle small and narrow; parafacia broad, approximately equal to width of basoflagellomere, brownish black, shiny, with white pilosity of moderate length; gena moderately broad, shiny, with few white pilosity. Frons slightly inflated, very broad, densely grey pollinose and black pilose, frontal angle distinctly obtuse (> 90°); lunule yellow, antennal pits separated. Antenna: scape black, pedicel brown, basoflagellomere black in antero-dorsal part and orange in postero-ventral part, rounded; arista short, black, almost bare. Eye entirely with long, dense, white pilosity, eye contiguity almost equal to length of frons without lunule. Vertex slightly inflated, covered with black pilosity, ocellar triangle obtuse. Occiput with black pilosity.

THORAX. Postpronotum black, finely pollinose and short white pilose. Scutum and scutellum black, smooth, very fine-punctured, shiny black with bluish reflection, with white and black pilosity, black pile longer, especially on hind part of scutum and scutellum; postalar callus with some black pilosity; scutellum hind margin with some long, bristle-like black pilosity. Subscutellar fringe with not very dense white pilosity. Pleura black, with comparatively dense, grey pollinosity; posterior part of anepisternum with non-pollinose shiny patch, with whitish pilosity, postero-dorsal part of anepisternum with some black pilosity, dorsal and ventral white hair patches on katepisternum connected medially. Metasternum white pilose.

LEGS. Fore coxa without lateral spur, brown with grey pollinosity and white pilosity; femora dark-brown to blackish with yellow tips, long pilosity on posterior side of fore and mid femora white, with some black pilosity near tips, antero-ventral surface of hind femur without long pilosity; tibiae yellow with narrow black annulus, hind tibia with broader blackish annulus; tarsi yellow ventrally, dorsally fore and hind tarsi black, mid tarsi with segments 1–3 yellow, segment 4 brown and segment 5 black.

WING. Translucent, entirely microtrichose, Rs with 1–2 yellow, short pile; inner angle between veins M 1 and R 4+5 right. Haltere yellow, with unusually big, black knob; calypter white, with yellow rim and white fringe.

ABDOMEN. Narrow, in broadest part approximately as broad as scutum at level of wing base, brownish black with some brown pollinosity, laterally and most of tergite IV shiny, white pilose, pilosity long, erect laterally and short, appressed medially. Sternites brown, shiny, sternite I with grey pollinosity, with long, white pilosity on sternites I–II and laterally on sternites III–IV, and with semi-erect, black pilosity medially on sternites III–IV which is shorter medially and longer on posterior margins. Genitalia as in Fig. 41F–I .

Female

LENGTH. Body 4.6–5.1 mm, wing 4.3–4.6 mm.

HEAD. Parafacia broad, approximately equal to half of basoflagellomere width, brown, paler ventrally, with long, pale-yellow pilosity. Frons broad, slightly broadened anteriorly, shiny black with two distinct lateral furrows and rather indistinct medial furrow, covered with short black and white pilosity. Basoflagellomere bigger than in male, of same shape and colour.

THORAX. Scutum and scutellum with short, erect white pilosity, and with ca 2× longer black pilosity in the posterior half, postalar callus with short, black bristles; scutellum hind margin with two longer black bristles in addition to some short bristles. Pleura with only white pilosity.

ABDOMEN. Non-pollinose, shiny. Other characters as in male.

Distribution

Nepal.

Figures

Fig. 41. Cheilosia (Montanocheila) minuscula sp. nov.; A–C, F–I = holotype, ♀ (CSCA), D–E = paratype, ♂ (CSCA). A. Head, lateral view. B, E. Antenna, lateral view of pedicel and basoflagellomere. C. Tip of wing. D. Head, dorsal view. F–G. Superior lobes of hypandrium, lateral view. H. Aedeagus and aedeagal apodeme, lateral view. I. Surstylus and gonocercus, lateral view. Scale bars indicated in drawings.

Fig. 42. Cheilosia (Montanocheila) minuscula sp. nov. A–B. Holotype, ♀ (CSCA); dorsal and lateral views. C. Paratype ♀ (CSCA); dorsal view. Photo: Pekka Malinen, FMNH Luomus. Scale bars = 1 mm.