Gymnochiromyia maculiventris, 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 : 91-92

Gymnochiromyia maculiventris sp. n.

Figs 1 , 2e , 9 , 10

Etymology: From Latin macula (spot) and venter (abdomen); the combination refers to the abdominal spots.

Diagnosis: Males have a brown spot on the ep and females have a brown spot on the midline of tg 2–7 (sometimes restricted to tg 5–7); acrs in 6–8 irregular rows at the level of the transverse suture, mtn yellow to brown; the apical section of Cu is equal to the distance between the crossveins.

Description:

Male.

Head: All yellow except for black oc triangle; fr (distorted in type; description supplemented from paratype with same data) broader than half width of head, narrowed anteriorly, at level of antennae 0.7 width at level of anterior oc, and 0.5 width of one eye, viewed from in front; fr protruding above antennae. Gena recessed so that in profile it is distinctly narrower anteriorly; depth below middle of eye about 0.8 height of eye; gena yellow with pale setulae. ocp in profile clearly 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 of buccal margin relatively long especially the upper 4. Face depressed, with distinct but low linear carina. Antenna with both second and third segments equally pale, second with distinct short dark seta dorsally; third segment round, finely pubescent, hairs a little shorter than diameter of arista at base; arista black to base and completely bare. Chaetotaxy: 3 strong orbs, anterior slightly inclinate, middle and posterior orb reclinate but also somewhat divergent, middle orb closer to first than the hind orb; about 10 fine pale setulae on orb plate between orb; in addition, about 16 fine pale brown setulae scattered on fr; pvt cruciate, about half length of hind orb; 1 vti and 1 vte; oc as long as hind orb, proclinate and divergent.

Thorax: msn, scut and pleura all yellow; mtn pale brown. Chaetotaxy: 1 hu, 1 psthu, 2 ntpl, 1 sa, 1 pa, 2 dc decreasing in size from back to front, acrs in 6–8 irregular rows at transverse suture; 2 longer distinct prescutellar acrs; 1 mspl, 1 stpl, both with a few setulae in front.

Wing: Hyaline, veins all pale yellow, distance on costal margin between R 2+3 to R 4+5 is 0.7 that between R 4+5 and M 1+2; distance between crossveins equal to length of apical section of Cu. Haltere yellow.

Legs: Not modified except for slightly thicker fore and hind femora; generally fine yellow setulae scattered on all pairs of legs and in addition longer setae present on fore femur.

Abdomen: All tg and st yellow and with pale setae.

Postabdomen: ep with a black almost triangular spot on posterior surface; this spot, even when large, does not extend as far as anterior margin or posteroinferior margin of ep, cerci small and finely setulose; surs long, curved, with slightly undulating outline and distinct seta directed laterally at apex; hyp broad and short; ph apd narrow and well sclerotised and more curved than usual; ej apd and tubule distinct, but small; prg triangular and setose on outer surface below, psg not identified; distiphallus asymmetrical and relatively small and simple.

Female.

Differs as follows: msn with a short dark mark just lateral to dc line posteriorly; abdomen with brown spot on middle of tg 2–7; setae and setulae stronger; postabdomen ( Fig. 10 ) with paired sclerites of st 8 comparatively small, but each with strong setae placed on minute tubercles.

Length: ♂ 1.6 mm, wing 1.6 mm; ♀1.7 mm, wing 1.8 mm.

Variation: Markings on msn generally absent in males, but variably present in females and vary in intensity of pattern and colour; posterior crossvein often oblique and distance between crossveins sometimes equal to apical section of Cu; dc may be better developed in females but there is never one in front of suture; in darker specimens, setae and setulae are often dark brown almost black; mtn varies from yellow (the more usual) to brown.

Holotype: ♂ SOUTH AFRICA: Western Cape: Mossel Bay , vii.1938, R.E. Turner ( NHML, B.M. 1939-98) .

Paratypes: SOUTH AFRICA: Western Cape: 1 ♂ 1♀same data ( NHML, B.M. 1939-98); 1 ♂ 1♀same data ( NMC) ; 1 ♂ same data ( NMSA) ; 1 ♂ 3♀same data, but vi–vii.1930 ( NHML, B.M. 1930-402); 1♀Mossel Bay, ii.1922, R.E. Turner ( NHML, B.M. 1922-97); 1♀Mossel Bay , v.1936, R.E. Turner ( NHML, B.M. 1930-266); 1♀Cape Hermanus, Hoy’s Hill , 7.x.1993, 34º25'S: 19º14'E, 60 m, Flowers & Dassie hole, J.G.H. Londt (NMSA) . Eastern Cape: 1♀Aliwal North, xii.1922, R.E.Turner ( NHML, B.M. 1923-45); 1♀Katberg, 1–10.ii.1933, R.E. Turner ( NHML, B.M. 1939-139); 1♀Barkly East District , Lundeans Nek , 1925–2000 m, 18.i.1963, B. & P. Stuckenberg ( NMSA) . KwaZulu-Natal: 1♀Eshowe, 6–31.v.1926, R.E.Turner ( NHML, B.M. 1926-232); 5♀Pietermaritzburg , 6.i.1954, 16.xi.1954, 24.xi.1954, 25.xi.1954, 1.xii.1954, B. Stuckenberg ( NMSA) ; 3♀Pietermaritzburg , 17.x.1983, 18.x.1983, on window, R.M. Miller ( NMSA) ; 1♀Pietermaritzburg , 20.i.1993, 29º34'S: 30º20'E, 900 m, Montrose house, J.G.H. Londt ( NMSA) .

Figures

Fig. 1. Gymnochiromyia maculiventris sp. n., wing. Scale bar = 1 mm.

Fig. 2. Gymnochiromyia, posterior aspect of ep, semidiagrammatic, with setae omitted and cerci in outline: (a) gilva sp. n., (b) maraisi sp. n., (c) setulosa sp. n., (d) balteata sp. n., (e) maculiventris sp. n., (f) punctata Ebejer.

Figs 8, 9. Male hypopygia, lateral aspect: (8) G. gilva sp. n., (9) G. maculiventris sp. n. Scale bars = 0.2 mm.

Fig. 10. G. maculiventris sp. n., female postabdomen, lateral (a) and ventral (b) views, and (c) spermatheca, enlarged. Scale bar = 0.2 mm.