Gymnochiromyia pretoriella, 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 : 100-102

Gymnochiromyia pretoriella sp. n.

Fig. 20

Etymology: Named after Pretoria, the South African city where it was found.

Diagnosis: This is a small entirely yellow species with the hypopygium distinctly larger than is usual in the genus: it forms approximately 1/3 the volume of the whole abdomen, whereas in other species 1/5 to 1/4 is more typical. Otherwise, there are no external distinguishing features.

Description:

Male.

Head: All yellow except for brownish oc triangle; fr narrower than half width of head, markedly narrowed anteriorly: at level of antennae 0.4 width that at level of anterior oc and 0.6 width of one eye viewed from front. Gena, more or less symmetrically rounded lower margin; in profile, below middle of eye, about equal to height of eye; yellow and pale haired. ocp in profile barely visible behind eye, with short postocular setulae in one irregular row; isolated lower post-genal seta long and golden yellow. Mouthparts small, all yellow; setulae on oral margin short. Face poorly sclerotised and depressed, barely visible.Antenna yellow, second segment paler than third with distinct short pale brown seta dorsally; third segment round, finely pubescent: hairs shorter than diameter of arista at base; arista brown almost throughout and completely bare. Chaetotaxy: 3 strong orbs, anterior inclinate and closer to middle orb than latter is to hind orb; pvt short, but distinct and crossed; 1 vti and 1 vte; oc about half length of hind orb, proclinate and lateroclinate; about 4 minute pale setulae across middle of fr, none on orb plate.

Thorax: Entirely yellow including mtn. Chaetotaxy: 1 hu, 1 psthu, 2 ntpl, 1 short pra, 1 sa, 1 pa, 1 dc, acrs very short in 6–8 irregular rows, one prescutellar pair distinctly longer; 1 mspl, 1 stpl.

Wing: Hyaline, veins all pale yellow, distance on costal margin between R 2+3 to R 4+5 is 0.8× that between R 4+5 and M 1+2; distance between crossveins about 0.5 length of apical section of Cu. Haltere yellow.

Legs: Not modified except for very slightly thicker femora; fine setulae scattered on all pairs of legs, in addition to somewhat longer setae on fore femur.

Abdomen: Entirely yellow, tg relatively short with numerous setae and setulae, longest about half as long as tg.

Postabdomen: Hypopygium about as large as the preceding two visible abdominal segments together; ep large without markings, but with distinct seta at the ventrocaudal angle; surs short but distinct and slightly curved medially at apex; cerci very small and finely setulose; hyp distinctly broader basally in profile; ph apd short, narrow, broad only at base; ej apd very small and tubule visible; prg trapezoidal and setulose on margin; psg not identified, ph complex, subquadrate and asymmetrical.

Female.

Similar to male except for absence of secondary sexual characters; and setae more brownish.

Length: ♂ 1.2 mm, wing 1.2 mm; ♀1.4 mm, wing 1.4 mm.

Variation: None noted.

Holotype: ♂ SOUTH AFRICA: Gauteng: Pretoria , Roodeplaat Dam N.R., 25 km NE Pretoria, 2.i.1995, A. Freidberg ( TAU).

Paratypes: SOUTH AFRICA: Gauteng: 1♀same data and depository as holotype; 2 ♂ Hartbeespoort , 25 km W Pretoria, 30.xii.1994, A. Freidberg ( TAU).

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.