Cheilosia spinosa, 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 : 105-109

Cheilosia spinosa sp. nov.

urn:lsid:zoobank.org:act:820003D3-1D4B-4B52-874D-A31CE817B6FD

Figs 58–59

Differential diagnosis

Cheilosia (Cheilosia) spinosa sp. nov. is most similar to Nepalese species Cheilosia (C.) spuria sp. nov. and to C. (C.) nadiae Barkalov & Cheng, 2004 described from China. Cheilosia (C.) spinosa sp. nov. is distinguished by having an orange basoflagellomere, semi-erect to appressed pilosity on mesonotum and abdomen, a broader frons in anterior part and shorter pilosity on eye. In C. (C.) spuria sp. nov. and C. (C.) nadiae the basoflagellomere is black, mesonotum and abdomen mostly with erect pilosity, and frons narrower in anterior part, and pilosity of eye is longer. C. (C.) spuria sp. nov. is most similar to C. (C.) nadiae , from which it differs in pattern of pollinosity of face and differences of male genitalia.

Etymology

The specific epithet is from the Latin ‘ spinosus ’ meaning ‘spiny’ and refers to the presence of a basolateral spur on the fore coxa.

Material examined

Holotype NEPAL • ♂; Prov. Karnali, Umg. Lager oberhalb Maharigaon [surroundings of camp above Maharigaon]; 29°20′24″ N, 82°23′21″ E; 3300–3400 m a.s.l.; 20 Jun. 1997; J. Weipert leg.; BSJW/ NME.

Paratypes NEPAL • 1 ♀; same data as for holotype; BSJW / NME • 1 ♀; Maharigaon Nördl.; 29°20′24″ N, 23°21′ E; 3400 m a.s.l.; 20 Jun. 1997; Creutzburg leg.; “ Weissschale ”; IBSJW / NME .

Description

Male

LENGTH. Body 8.1 mm, wing 8.0 mm.

HEAD. Face moderately broad, slightly widened ventrally, shiny, whitish-grey pollinose ventral to antennal base and medio-laterally; facial tubercle distinct, rounded; parafacia moderate in width, approximately ¾ of width of basoflagellomere, brownish to dark-brown, paler in ventral ⅔, densely silvery pollinose and short white pilose; gena narrow, grey pollinose with white, dense pilosity of moderate length. Frons slightly convex, densely grey pollinose and black pilose, frontal angle slightly obtuse; lunule pale-brown, with a clear dividing grey pollinose medial furrow, antennal pits separated. Antenna: scape black; pedicel brown medially and black along basal, anterior and ventral margins; basoflagellomere pale-brown with postero-ventral orange spot; arista long, brown, bare (short, inconspicuous, adpressed pilosity visible under very high magnification). Eye short white pilose, eye contiguity distinctly longer than length of frons without lunule. Ocellar triangle isosceles. Vertex distinctly convex, with long, fine, black pilosity, dorsally with short white and long black pilosity.

THORAX. Postpronotum black, densely whitish-grey pollinose, with short white semi-erect pilosity. Scutum fine-punctured, black, mostly very shiny, grey pollinose on notopleural area, with short, semierect yellow and 2–5× longer black and yellow pilosity, and laterally also with long, fine, black bristles; postalar callus narrowly yellow anteriorly and posteriorly, with shorter yellow pilosity and up to 5× longer black bristles; scutellum with short appressed black pilosity and very long black bristles, hind margin with many long, strong, black bristles, longer than length of scutellum. Subscutellar fringe with long, dense, white pilosity. Pleura densely grey pollinose and mostly long white pilose, patch of black pilosity on postero-dorsal corner of anepisternum, katepimeron only white pilose, ventral and dorsal yellow pile patches of katepisternum distinctly separated. Metasternum short white pilose.

LEGS. Fore coxa black, densely grey pollinose, laterally with a distinct spur, short white pilose; femora black with extreme tips of fore and mid femora brownish, fore femur distinctly convex in basal ⅔, posterior long pilosity white, mid femur posteriorly with white and some black pilosity near tip, hind femur ventrally without long pilosity, with strong black and brown bristles with length about ⅔ of width of femur, anteriorly with some long white pile longer than width of femur; fore and mid tibia yellow with more or less broad black annulus in apical half, hind tibia mostly black, brownish in basal ⅓; tarsi black dorsally, with only metatarsus of mid leg yellow in basal half.

WING. Entirely microtrichose, with brownish veins; Rs without pilosity; inner angle between veins M 1 and R 4+5 nearly right. Haltere yellow, with knob dark-brown; calypter white with brownish-yellow rim and fringe.

ABDOMEN. Narrow, elongate, slightly narrower than scutum at level of wing base, black with bluish reflection, laterally about ¼ of tergites and posterior ¾ of tergite IV shiny, medially with dense brown pollinosity; with long white pilosity on tergites I–II and lateral parts of tergite III which, tergites I–III latero-medially also with short erect white pilosity, tergites III–IV medially with very short, appressed black pilosity. Sternites brownish, with grey pollinosity, sternites I–II only white pilose, sternite III white pilose on anterior half and with mixed appressed black and semi-erect whitle pilosity of different lengths on posterior half, sternite IV on anterior ¼ with appressed white pilosity and on posterior ¾ with appressed black pilosity. Genitalia with black pilosity.

Female

LENGTH. Body 10.2 mm, wing 8.5 mm.

HEAD. Face comparatively broad, distinctly broadened ventrally, moderately protruded forward, non-pilose; facial tubercle distinct, protruded, shiny; parafacia broad, somewhat broader than half of basoflagellomere width, black in dorsal ⅓ and brownish-orange in lower ⅔; finely grey pollinose, with appressed short white pilosity. Gena orange near eye and black otherwise, densely grey pollinose, and with white pilosity of moderate length. Lower part of occiput covered with grey pollinosity and white pilosity. Frons distinctly broadened anteriorly, with distinct lateral furrows, medially on anterior third with a short longitudinal furrow; grey pollinose near lunule and eye, otherwise shiny; covered with anteriorly inclined short yellow and black pilosity. Antennae: scape and pedicel dark-brown, basoflagellomere enlarged, rounded, orange to brownish orange, with darker antero-dorsal margin. Vertex flat, ocellar triangle isosceles; occiput in upper part shiny, without pollinosity, long black and short white pilose.

THORAX. Scutum with distinct puncturation, shiny, notopleural area slightly grey pollinose; with short appressed yellow and black pilosity, notopleura with one strong black bristle transverse suture posterolaterally and postalar callus with some moderately long and strong black bristles; scutellum shiny, with short, appressed black pilosity, hind margin with short and some long, strong black bristles not exceeding length of scutellum; scutellar fringe with mixed long and short white pilosity. Pleura densely grey pollinose, only posterior anepisternum and upper part anterior anepimeron with small macula without pollinosity; katepisternum with ventral and dorsal pile patches narrowly separated.

LEGS. Fore coxa with distinct spur, black, and anteriorly pollinose, brown and shiny posteriorly. Mid coxa brownish, grey pollinose and short white pilose. Hind coxa black, densely grey pollinose and long white pilose. Femora black with narrowly yellow base and tip, densely grey pollinose and comparatively short white pilosity; hind femur without long antero-ventral pilosity, with short black pile ventrally on apical

⅔. Fore and mid tibiae yellow, with black annulus in apical half; hind tibia black with brownish basal ⅕ and tip. Tarsi black, but fore and mid metatarsi yellow.

WING. Elongated, brownish, entirely microtrichose, inner angle between venae M 1 and R 4+5 acute. Haltere yellow with slightly darker knob; calypter pale yellow with yellowish rim and pile.

ABDOMEN. Elongated, broadest in posterior part of tergite II, shiny but tergite I completely and tergites II–IV medially with grey pollinosity, tergite V only very slightly pollinose antero-medially; pilosity white, long, erect on sides of tergites I–II and short, appressed otherwise; tergites IV–V also with some short black appressed pile postero-laterally. Sternites dark, densely grey pollinose; sternite V with appressed black pilosity. Other characters as in male.

Remarks

The presence of a baso-lateral spur baso-laterally on fore coxa is a distinct character present known in three Palearctic species of Cheilosia : C. (C.) impressa Loew, 1840 , C. (C.) schnabli Becker, 1894 and C. (C.) nadiae Barkalov & Cheng, 2004 . This character is present in three additional species from Nepal, C. (C.) falcata sp. nov., C. (C.) spinosa sp. nov. and C. (C.) spuria sp. nov. The structure of the male genitalia (especially the superior lobes) are different in all these taxa.

Distribution

Nepal.

Figures

Fig. 58. Cheilosia (Cheilosia) spinosa sp. nov.; A, E–I = holotype, ♂ (BSJW/NME), B–D = paratype, ♀ (BSJW/NME). A–B. Head, lateral view. C. Head, dorsal view. D. Tip of wing. E. Antenna, lateral view of pedicel and basoflagellomere. F. Fore coxa. G. Superior lobe of hypandrium, lateral view. H. Surstylus and gonocercus, lateral view. I. Aedeagus and aedeagal apodeme, lateral view. Scale bars indicated in drawings.

Fig. 59. Cheilosia (Cheilosia) spinosa sp. nov.A–B. Holotype, ♂ (BSJW/NME); dorsal and lateral views. C–D. Paratype, ♀ (BSJW/NME), dorsal and lateral views. Photo: Pekka Malinen, FMNH Luomus. Scale bars = 1 mm.