Oroschyromya gracilipes, 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 : 364-366

Oroschyromya gracilipes sp. n.

Fig. 22

Etymology: From Latin gracilis (slim) and pes (foot), and refers to the relatively long slim legs of this species.

Diagnosis: Orange species with black rectangular patch at anterior margin of scutum above ocp foramen and pair of broad dark brown stripes on posterior half of scutum; femora are long and slender, basitarsus of middle leg ventrally with modified setulae.

Description:

Male.

Head: Orange-yellow except for brown oc triangle; fr long and narrow, at anterior oc about 0.8 width of eye; at level of antennae 0.4 width that at level of anterior oc. Gena: narrow, about 0.3 height of eye; yellow and pale haired; ocp in profile slightly convex; few short postocular setulae in one irregular row; isolated lower postgenal seta absent. Mouthparts small, all yellow; vibrissal setulae all short. Face poorly sclerotized and depressed. Antenna yellow with dark brown line along anterior and dorsal margin and pale brown infuscation laterally near base of arista; second segment yellow with distinct short dark seta dorsally; third segment round, finely pubescent: hairs not quite as long as diameter of arista at base; second segment black almost throughout and first and second segments light brown and shorter than usual for this family. Chaetotaxy: 3 strong orb, all inclinate, pvt distinct and crossed; 1 vti and 1 vte strong; ocellars lateroclinate; about 12 very short black setulae across middle of fr.

Thorax: Deep orange-yellow and somewhat elongated; a pale brown line runs from just medial to pprn to transverse suture; another dark brown stripe runs from behind suture to edge of scut along dc line, becoming broader posteriorly. scut with dark brown line along superior lateral margin; on meron at base of haltere with brown spot, otherwise all pleura orange-yellow. Chaetotaxy: prpl absent, 0+2 strong dc, scutal setulae few in number and very irregular, approximately in 4–6 rows with one short but distinct prscut pair; 3 or 4 irregular rows of setulae also between dc and sa lines; 1 pprn, 1 posthu, 2 ntpl, 1 sa and 1 pa, 1 post ia; 2 pairs of marginal scut setae: one subapical and one basal, no setulae on margin or on disc; anepisternum with 1 strong seta directed backwards at middle of posterior margin and about 10 short setulae in front, katepisternum with 1 strong seta at upper posterior corner and 3 short setulae in front; tuft of setulae at ventral angle with fewer, finer shorter and very pale; all other setae and setulae brown to black.

Wing: Uniformly pale brown infuscated and with pale brown veins; anal cell with minute stump vein; distal section of Cu about 3.5× length of posterior crossvein; distance between crossveins about 1.7× length of posterior crossvein and 0.8× length of apical section of Cu; distance on costal margin between R 2+3 and R 4+5 about 0.8 that between R 4+5 and M 1+2, latter two veins slightly convergent towards wing apex. Haltere yellow. Legs: Modified, rather longer and slimmer than is usual for this family; fine setulae scattered on all pairs of legs; in addition longer setae present on fore femur, but these are not as long as is usual in this family; setulae on dorsal aspect of tarsomeres of all legs distinctly longer; basitarsus of middle leg, ventrally with 3 irregular rows of spinescent setae, most of which are longer than diameter of basitarsus; hind femur with a row of fine setae on anteroventral and posteroventral aspect; hind tibia with 2 parallel rows of ventral setae in apical 2/3; mid tibial apicoventral seta absent; claws black and pulvilli normal; hind trochanter normal.

Abdomen: Orange, slightly compressed laterally and with well sclerotized brownish dorsal tg plates; tg 6 narrow but separate from ep; st thinly sclerotized; st 5 with ventrally directed pair of narrow projections and long setae on sides of posterior margin. Short setae on disc of tg and on hind margin with setae almost as long as tg; st 4 and 5 also with very long marginal setae.

Postabdomen: ep well-developed and elongated dorsoventrally with distinctly rounded dorsal aspect; large posteroventrally directed opening; cerc large, long, narrow and sclerotized with a few very fine setulae, hyp distinct and broad, ph apd curved and at apex divided into lateral lobes, ej apd not identified; prg in form of large, heavily sclerotized, anteroventrally directed spine; surs similarly long, but curved posteroventrally; distiph large with sclerotized and membranous components.

Female: Unknown.

Length: ơ body 2.1 mm, wing 1.9 mm.

Holotype: ơ UGANDA: Budongo forest, Masindi District, 01°45'N: 31°35'E, alt. 1200 m, seasonal rain forest, fogged from Cynometra alexandri (Caesalpiniaceae) , nr Somso R., vi.1995, Wagner (in alcohol, ZSMC).

Figures

Fig. 22. Oroschyromya gracilipes sp. n., ơ: (a) hind leg, anterior aspect; (b) basitarsus, middle leg, lateral; (c) hypopygium, lateral; (d) distiph, lateral; (e) st 5, lateral; (f) same, ventral. Scale bars = 0.3 mm in Figs 22a–c and 0.2 mm in Figs 22d–f.