Coenosia fragilis, Couri, Márcia & Pont, Adrian C., 2014

Couri, Márcia & Pont, Adrian C., 2014, New species of Afrotropical Muscidae (Diptera: Muscoidea), Zootaxa 3852 (3), pp. 301-320 : 306-307

Coenosia fragilis sp. nov.

Figs 10–12.

Type material. Holotype ♂, DEMOCRATIC REPUBLIC OF THE CONGO: Oriental Prov., Lieki village area at 00° 41.117 ′N, 24 ° 14.362 ′E, sweeping bush paths & village environs, 25.v– 4.vi. 2010 (A.H. Kirk-Spriggs), BECE 02922 ( ISNB).

Paratype, 1 ♂. DEMOCRATIC REPUBLIC OF THE CONGO: same data as holotype, except: BECE 02918 ( BMSA).

Diagnosis. Very small species; ground-colour brown with metallic reflexion, including legs; ocellar seta strong; frontal vitta, fronto-orbital plate, face, parafacial and gena densely yellowish silvery pruinose (viewed from certain angles); palpus brown. The new species belongs to the C. niveifrons species-group sensu Emden ( 1940). In Emden’s ( 1940) key, it runs to couplet 14 ( 17), due to the presence of strong ocellars, but is not C. multisetosa Emden or C. fumisquama Stein , which also have dark head pruinosity and long frontal setae.

Description. General colouration. Ground colour brown, with metallic reflexion; frontal vitta, fronto-orbital plate, face, parafacial and gena densely yellowish silvery pruinose (viewed from certain angles); antenna black; palpus brown; notum dark brown, matt; prescutum including postpronotal lobe and notopleuron and anterior ½ of scutum, with silvery reflexion (viewed from certain angles); pleura thinly grey dusted, with metallic reflexion; spiracles dull; wing hyaline; calypters white, lower one yellowish around margin; haltere brown; legs black, femora and tibiae shining; abdomen dark brown, with some grey dust on sides of tergites; epandrium shining black.

♂. Measurements. Body length: 2.2 mm; wing length: 2.2 mm.

Head. Eye bare, frons at vertex a little more than ⅓ of head-width, markedly narrowing to lunule; 3 pairs of fine frontal setae, the second one from lunule short, and 1 fine reclinate orbital; inner vertical seta long; ocellar seta long; antenna inserted above mid-level of eye, with postpedicel about 1.5 the length of pedicel; arista with very fine and short pubescence, hardly as long as width of arista at base; palpus filiform, with apex a little flattened and enlarged.

Thorax. Dorsocentrals 1 + 3; acrostichal setulae short and sparse, in 2 irregular rows, prescutellar slightly longer than others; 1 postpronotal; 2 postsutural intra-alars; 1 postsutural supra-alar; 2 postalars; prealar absent; notopleuron with 2 setae similar in size; anepisternum with series of 6 setae, most long; katepisternals 1 + 1 + 1, arranged in equilateral triangle, dorsal posterior seta very long. Scutellum with 1 basal and 1 long apical pair of setae, the basal ca ⅔ length of the apical.

Legs. Fore femur with row of well-spaced setae on posteroventral and posterodorsal surfaces; fore tibia with long posterior median seta, 1 dorsal and 1 long fine anterodorsal preapical and 1 apical seta on posterior, posteroventral and posterodorsal surfaces; mid femur with ca. 4 fine anterior to anterodorsal setae; anteroventral surface with row of fine setae in basal ⅔, with a few longer sparse posteroventrals, 2 posterior preapicals; mid tibia with 1 anterodorsal and 1 posterodorsal median setae; hind femur with sparse rows of anterodorsal and anteroventral setae, 2 fine posteroventrals in apical ½, 1 preapical posterodorsal seta; hind tibia with 1 anterodorsal and 1 anterior median setae, 1 long dorsal and 1 anterodorsal preapical and 1 apical ventral.

Wing. Veins bare; veins M and R 4 + 5 parallel at wing-tip; lower calypter long, ca. 2.3 × length of upper.

Abdomen. Tergite 5 with 4 marginal setae; sternite 1 bare; sternite 5 as in Fig. 10.

Terminalia . Cercal plate with 5 strong spines ( Fig. 11); epandrium, cercal plate, surstylus and aedeagus as in Fig. 12 (lateral view).

♀ Unknown.

Distribution. Democratic Republic of the Congo (Oriental Province).

Etymology. The specific epithet fragilis is a Latin adjective (“fragile”) and refers to the small size of the species.