Gymnochiromyia nubilipennis, Ebejer, 2008

Ebejer, M. J., 2008, New species of Gymnochiromyia Hendel, 1933 (Diptera: Schizophora: Chyromyidae) from Southern Africa, African Invertebrates 49 (1), pp. 77-77 : 99-100

Gymnochiromyia nubilipennis sp. n.

Fig. 19

Etymology: From Latin nubilus (cloud) and penna (wing); the combination refers to the coloured patch on the wing of the males.

Diagnosis: This species is characterized by unusually long setae especially vertical and scut; by 2 black msn stripes lateral to dc lines that may continue on to lateral boarder of the scut; male with a brown patch in anterior half of apical third of wing. Among the Chyromyidae known so far, this is the only species that has a coloured patch on the wing in the male.

Description:

Male.

Head: Somewhat shrivelled, yellow with black oc triangle; fr narrowing towards antennae, yellow (discoloured posteriorly due to post mortem changes) with about 8 fine white setulae; gena pale yellow about 0.65 height of eye; face poorly sclerotised and depressed; antenna yellow, third segment with dense fine pubescence around anterior margin; second segment with long yellow seta dorsally; arista black almost to base of third segment, but first two segments all yellow; peristomal setae white, as long as those on gena; isolated post-genal seta long; postocular setulae long and 2 irregular rows; vti and vte very long, vti about twice as long as hindmost of 3 orb; oc and pvt of equal length and about as long as anterior orb.

Thorax: msn pale brown; anteriorly just above neck a pair of very short broad black confluent stripes narrowly separated in midline only posteriorly, these do not extend beyond hind margin of hu; lateral to these and medial to hu, but set back a little is a round black spot; in line with this but commencing behind transverse msn suture is another narrower black stripe that continues along lateral boarder of scut and on to mtn, itself all black; viewed from above, hu and ntpl appear contrastingly pale yellow; pleura entirely pale yellow apart from dark brown spot on hypl and around base of haltere. Chaetotaxy: 0+2 dc set far back, acrs in 6 irregular rows, prescutellar pair almost as long as hind dc, 2 hu, (one long, one short), 1 psthu, 2 ntpl, 1 short pra (in holotype only), 1 sa, 1 pa, 2 usual pairs of scut but apical pair almost twice as long as basal pair, 1 mspl, 1 stpl, in addition several long white setulae on both sclerites.

Wing: Veins brown except M vein along discal cell and posterior cross vein, both of which are very pale yellow; wing membrane with oval brown patch in apical half extending from costa to midway between R 4+5 and M 1+2 and sparing the wing apex; setulae on first costal section unusually long, about 1.5 to 2 thickness of costa; distance on costal margin between R 2+3 to R 4+5 is 0.5 that between R 4+5 and M 1+2; distance between crossveins about 0.7 length of apical section of Cu. Haltere yellow.

Legs: All yellow and yellow setulose without special modifications apart from slightly dilated femora.

Abdomen: tg dark brown, moderately shining; only extreme lateral margin yellow; dark brown setulae about as long as tg.

Postabdomen: ep dark brown, cerci pale and finely setulose; surs short, broad at base, curved and markedly tapering to a blunt end at apex; hyp broad and short; ph apd narrow and poorly sclerotised; ej apd small, indistinct and bilobed; prg large, trapezoidal and finely but densely setulose, psg small; ph asymmetrical and enlarged giving the impression of being spherical at apex.

Female.

Similar to male, but third segment of antenna with large brown spot on both sides, msn stripes shorter, msn dull yellow rather than pale brown, abdomen with lighter brown tg and wing without coloured patch.

Length: ♂ 1.6 mm, wing 1.5 mm; ♀1.7 mm, wing 1.9 mm.

Variation: Male paratype is more like the females in colouring and msn stripes much less developed; tg including ep brown only centrally; however, the wing marking extends beyond M vein towards hind margin.

Holotype: ♂ NAMIBIA: Brandberg District : Brandberg, Mason Shelter, 21º04'42"S: 14º35'33"E, 05– 14.iii.2002, 1750 m, light-trap, A.H. Kirk-Spriggs ( NMNW).

Paratypes: 2♀same data and depository; 1 ♂ 1♀same data (NMSA).

Figures

Figs 19, 20. Male hypopygia, lateral aspect: (19) G. nubilipennis sp. n., scale bar = 0.25 mm; (20) G. pretoriella sp. n., scale bar = 0.2 mm.