Coenosia albisquama ( Emden, 1940: 233 ) Emden, 1940

Couri, Márcia & Pont, Adrian, 2016, Species of Coenosia Meigen (Diptera, Muscidae) described by Fritz van Emden from the British Museum Ruwenzori Expedition of 1934 – 1935, Zootaxa 4144 (4), pp. 529-555 : 531-532

Coenosia albisquama ( Emden, 1940: 233) , stat. nov.

( Figs 47–49 )

Holotype male seen; in good condition.

Diagnosis. General colour brown; posterior part of scutum and scutellum brown; head strikingly silvery in male, frons and fronto-orbital plate strongly silver pollinose and strongly dilated to vertex, face and parafacial also strongly silver; wing infuscated; no ocellar setae in males; postpedicel dark brown; calypters whitish; arista shorthaired basad and bare apicad; palpus brown; haltere with knob dark brown; presutural and postsutural acrostichals present, long and fine; scutellum with four strong setae and with only one pair of subbasal setulae; anterior katepisternal short; lower calypter about 1.8 times the length of the upper one; legs shining brown; hind tibia with an anterior and an anterodorsal seta, the latter a little shorter; submedian posterodorsal seta absent; sternite 5 as in Fig. 47 .

Male terminalia. Cercal plate and surstylus as in Fig. 48 . Aedeagal complex as in Fig. 49 .

Notes. Included in the niveifrons group. Described by Emden (1940) as a subspecies of C. niveifrons Stein, 1913 . In addition to colour differences in the scutum and calypter and the long and fine acrostichals present in C. albisquama , the morphology of the male terminalia also showed differences in the shape and chaetotaxy of sternite 5, cercal plate, surstylus and aedeagus both from C. n. niveifrons ( Figs 101–103 ) and from C. niveifrons argentescens , also described by Emden as a subspecies and also elevated here to species rank. One paratype male was dissected and illustrated.

Coenosia argentescens ( Emden, 1940: 234) , stat. nov. ( Figs 25–28 ; 50–52)

Holotype male seen ( Figs 25–28 ); in good condition.

Diagnosis. General colour brown; scutum, scutellum and abdomen entirely silver pollinose; head strongly silvery in male, frons and fronto-orbital plate strongly silver pollinose and strongly dilated towards vertex in male, face and parafacial also strongly silver; wing infuscated; no ocellar setae in males; postpedicel dark brown; calypters whitish; arista short-haired basad and bare apicad; palpus brown; haltere with knob dark brown; presutural acrostichals absent; postsutural acrostichals very short and sparse; scutellum with four strong setae and with only one pair of subbasal setulae; anterior katepisternal short; lower calypter about 1.8 times the length of the upper one; legs shining brown; hind tibia with an anterior and an anterodorsal seta, the latter a little shorter; posterodorsal submedian seta absent. Sternite 5 as in Fig. 50 .

Male terminalia. Cercal plate and surstylus as in Fig. 51 . Aedeagal complex as in Fig. 52 .

Notes. Included in the niveifrons group. Described by Emden (1940) as a subspecies of C. niveifrons Stein, 1913 . The comments above under C. albisquama also apply here. In addition to the colour differences of scutum and calypter and the absence of presutural acrostichals, the morphology of the male terminalia also showed differences in the shape and chaetotaxy of sternite 5, cercal plate, surstylus and aedeagus both from C. n. niveifrons ( Figs 101–103 ) and from C. niveifrons albisquama , also described as a subspecies and also elevated here to species rank. One paratype male was dissected and illustrated.

Figures

FIGURES 41 – 52. Sternite 5; cercal plate and surstyli in dorsal view; epandrium, cercal plate, surstylus and aedeagus in lateral view: 41 – 43. Coenosia aequivitta (Emden). 44 – 46. Coenosia alba (Emden). 47 – 49. Coenosia albisquama (Emden). 50 – 52. Coenosia argentescens (Emden).

FIGURES 101 – 112. Sternite 5; cercal plate and surstyli in dorsal view; epandrium, cercal plate, surstylus and aedeagus in lateral view: 101 – 103. Coenosia niveifrons Stein. 104 – 106. Coenosia ruwenzorica Speiser. (syn: Coenosia kilembana syn. nov.). 107 – 109. Coenosia morio (Emden). 110 – 112. Coenosia somereni (Emden).

FIGURES 21 – 40. Dorsal habitus, lateral habitus, head in frontal view, and labels of types of Coenosia species: 21 – 24. Coenosia gracilipes (Emden), holotype male. 25 – 28. Coenosia niveifrons argentescens (Emden), holotype male (herein as C. argentescens stat. nov.). 29 – 32. Coenosia scutellaris (Emden), holotype male. 33 – 36. Coenosia somereni (Emden), holotype male. 37 – 40. Coenosia transversalis (Emden), holotype male.