Aphaniosoma trilobatum, Ebejer, 2009

Ebejer, Martin J., 2009, A revision of Afrotropical Chyromyidae (excluding Gymnochiromyia Hendel) (Diptera: Schizophora), with the recognition of two subfamilies and the description of new genera, African Invertebrates 50 (2), pp. 321-321 : 408-410

Aphaniosoma trilobatum sp. n.

Figs 53 , 54

Etymology: From Latin tri- (three-) and lobatus (lobed), and refers to the shape of the male postabdominal processes.

Diagnosis: Predominantly yellow species with 6 dark grey longitudinal stripes on scutum, rather longer setae and setulae, including those on gena, than in congeners, fr with 2 pairs of longer setulae, tarsomere 5 of all legs brown. Male postabdomen with three broad yellow lobes, easily visible without dissection and appearing to be part of same structure. However, when dissected these are surs, prg and tip of ep.

Description:

Male.

Head: Yellow, ocp dark brown except for broad yellow postocular margin and wedgeshaped area from vertex to neck, oc triangle black, fr broad but converging anteriorly so that at level of antennae it is about 0.7 as wide as at level of anterior oc, face small, depressed and with distinct, narrow but low facial carina, eye oval lying oblique, gena yellow, at middle about 0.5 height of eye and having numerous rather longer yellow setulae, 2 short setae at vibrissal corner, mouthparts yellow, 8 setulae on fr with 1 pair of longer setulae above lunule and another in front of oc triangle, 3 orb with 1 short setula in front, 1 vti and 1 vte, pvt distinct and convergent, ocellars long, divergent, antenna yellow, most of second segment of arista dark.

Thorax: Scutum and scut with yellow ground but with 6 dark grey longitudinal stripes on scutum, middle pair confluent anteriorly, scut a little pale brownish on disk, mtn brown, pprn and ntpl yellow, pleura mostly yellow except for a brown patch on anterior and lower part of anepisternum and an inverted dark grey triangle on each lower part of katepisternum and meron, base of haltere black. Chaetotaxy: 1 pprn, 2 posthu, 1 strong ihu, 2 ntpl, 0+4 ia, 2+5 acrs, 3+4 dc only the posterior one well-developed, prpl short, 1 pa, 2 pairs of marginal scut, 1 katepisternal with shorter seta in front and several setulae on anterior part of sclerite, 1 anepisternal, all setae pale brown and rather longer than those in other species described in this article.

Wing: Hyaline and uniformly microtrichose, veins pale brown, distance between R to R 4+5 on costal margin about 0.4 that between R 4+5 and M 1+2, distance between crossveins about 1.3× length of posterior crossvein and length of apical section of Cu about 2.3× length of posterior crossvein. Haltere yellow.

2+3

Legs: Yellow and fine yellow setulose, tarsomere 5 of all legs brown.

Abdomen: Brown with narrow, pale yellow hind margins to all tg.

Postabdomen: Yellow with brown ep spot above and lateral to cerc and with distinctly visible large yellow trilobed surs.

Female.

As male, but without secondary sexual characters. Postabdomen: tg 7 divided, st 7 elongate oval with setulae only at apex; tg 8 and st 8 each divided into small sclerites laterally; hypr not identified.

Length: ơ body 1.1 mm, wing 1.2 mm; ^body 1.5 mm, wing 1.6 mm.

Holotype: ơ NAMIBIA: Walvis Bay , alt. 5 m, 22°60'S: 14°28'E, 6.ix.2003, A. Freidberg ( TAUI).

Paratypes: NAMIBIA: 5ơ 7^same data as holotype ( TAUI) ; 1ơ 1^Lüderitz , alt. 20 m, 14.ix.2003, A. Freidberg ( TAUI) ; 1^Gobabeb , Kuseib R., 23°34'S: 15°03'E, 5.ix.2003, attacked by Laboulbeniales, A. Freidberg ( NMWC) ; SOUTH AFRICA: Western Cape: 1ơ De Hoop Nature Reserve , alt. 0–200 m, 34°27'S: 20°25'E, 10–13.x.1994, R. Danielsson ( MZLU) .

Figures

Fig. 53. Aphaniosoma trilobatum sp. n., ơ: (a) hypopygium, lateral, scale bar = 0.2 mm; (b) distiph, posterior; (c) st 6, ventral, scale bar = 0.15 mm.

Fig.54. Aphaniosoma trilobatum sp.n., ^postabdomen:(a) ventral, (b) lateral, (c) posterior,(d) spermathecae. Scale bar = 0.15 mm.