Coenosia argentipes ( Emden, 1940: 224 )

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 : 532

Coenosia argentipes ( Emden, 1940: 224)

( Figs 5–8 ; 53–55)

Holotype male seen ( Figs 5–8 ); left legs missing.

Diagnosis. General colour dark-brown; postpronotum grey dusted; frons velvety dark; face and parafacial strongly silver; mouth-margin slightly produced, forming a rounded prominence in dorso-frontal view ( Fig. 4 in Emden 1940: 93; Fig. 7 ); frons subparallel in its middle part, slightly diverging towards vertex (see note below), uniformly dusted; postpedicel about 1.8 times the length of pedicel and with pointed apex, inserted at about middle of eye; arista short-haired; palpus thin, brown, with extreme apex black; haltere yellow; scutellum with four strong setae and with setulae on disc; anterior katepisternal short, lower one about two-thirds of the length of the long posterior one; lower calypter about 1.8 times the length of the upper one; legs entirely black; hind femur and tibia of male with dense silvery pile on ventral surface; hind tibia with an anterior and an anterodorsal setae inserted at the same level, the anterodorsal a little shorter; submedian posterodorsal seta absent; sternite 5 as in Fig. 53 .

Male terminalia. Cercal plate and surstylus as in Fig. 54 . Aedeagal complex as in Fig. 55 .

Notes. Included in the niveifrons group. In the Emden’s group key ( Emden 1940: 159) one character to reach the niveifrons group is: “Frons distinctly dilated from first frontal seta to vertex”, but in some species of the group, such as this one, the frons is only slightly dilated towards vertex. The species is easy to recognise by the peculiar produced mouth-margin. One paratype male was dissected and illustrated.

Figures

FIGURES 1 – 20. Dorsal habitus, lateral habitus, head in frontal view, and labels of types of Coenosia species: 1 – 4. Coenosia aequivitta (Emden), holotype female. 5 – 8. Coenosia argentipes (Emden), holotype male. 9 – 12. Coenosia aristalis (Emden), holotype male. 13 – 16. Coenosia bipila (Emden), holotype male. 17 – 20. Coenosia ciliventris (Emden), holotype male.

FIGURES 53 – 64. Sternite 5; cercal plate and surstyli in dorsal view; epandrium, cercal plate, surstylus and aedeagus in lateral view: 53 – 55. Coenosia argentipes (Emden). 56 – 58. Coenosia aristalis (Emden). 59 – 61. Coenosia aurifacies Emden. 62 – 64. Coenosia brunneigena Emden.