Stenopomyia rhagioniformis Lyneborg

(Figs 35; 41C–D; 44O; 47I–J; 53)

Stenopomyia rhagioniformis Lyneborg, 1976: 234 —Lyneborg (1980: 319).

Diagnosis. Scutum brown with glossy dark brown spot laterally immediately posterior to transverse sulcus; abdomen yellow, male with tergites brown dorsally, terminalia black (female) or brown (male); antennal scape shorter than flagellum; male frons narrow, eyes contiguous below ocellar tubercle, without setae; legs yellow; prosternum lacking setae medially; two pairs of supra alar macrosetae, dorsocentral macrosetae absent; forefemur with anteroventral macroseta; epandrium with pointed posterolateral corners and billowed flange medially.

Redescription. Body length: 6.0–9.0 mm (male), 8.0– 10.5 mm (female). Head. Frontal profile flat, pubescence light brown dorsally, silver around antennal base, female with matte black spot above antennae, male frons width at narrowest point narrower than anterior ocellus but eyes not contiguous, male frontal vestiture absent, female with scattered, minute dark setae on upper frons; parafacial with silver pubescence; ocellar tubercle grey pubescent, without setae; postocular ridge with two or more rows of macrosetae irregularly arranged on occiput; occiput pubescence tan-brown; genal setae pale; antennal scape shorter than flagellum, cylindrical, dark yellow, scattered dark macrosetae of varying sizes; flagellum conical, tapered distally, brownish orange, darker distally. Thorax. Scutum brown, paler tan-brown dorsocentral stripes, dark brown spot laterally, immediately posterior to transverse sulcus (darker in female), erect fine admixed dark and pale setae, shorter in female; scutellum concolorous with scutum; prosternum without setal pile in medial furrow; pleuron yellow with sparse silver pubescence, glossy band posterior of katatergite, white setae on anepisternum, katatergite setae white; scutal and scutellar macrosetae black; coxae yellow, overlain with silver-grey pubescence, minor setae white, macrosetae black, few in number; femora dark yellow, short dark setae admixed with longer pale setae and black adpressed scale-like setae, femoral macrosetae black, forefemur with single anteroventral macroseta midway; midfemur with macrosetae absent, hind femur with single subapical anteroventral macroseta (sometimes absent), subapical series of short posteroventral macrosetae; tibiae dark yellow with black suffusion; tarsi brown; wing uniform smoky infuscate, venation brown, cell m 3 open; haltere dark yellow; scutal chaetotaxy: notopleural, 3; supra alar, 2; post alar, 1; dorsocentral, 0; scutellar, 1–2. Abdomen. Male abdomen dark brown dorsally, yellow laterally, silver velutum laterally on tergites 1–3, male vestiture mostly elongate pale setae, denser laterally; female abdomen dark yellow, segments 7–8 black, vestiture as short, erect black setae on all segments; terminalia brown. Male genitalia. Epandrium broad, trapezoidal with posterolateral corners pointed, setae sparse; hypandrium absent; outer gonocoxal process relatively short, rounded; inner gonocoxal process narrow, spatulate with elongate setae apically; gonostylus longer than outer gonocoxal process, with fringe of setae; ventral lobe elongate; distiphallus relatively short and narrow, reflexed ventrally; dorsal apodeme narrow.

Comments. Stenopomyia rhagioniformis is placed in the keiseri species group and is closely related to S. holops sp. nov. The two species can be separated by the presence of two supra alar macrosetae (one in S. holops sp. nov.) and a single anteroventral macroseta on the forefemur (absent in S. holops sp. nov.) in S. rhagioniformis. The glossy black-brown spot laterally on the scutum is unique to this species.

Distribution. Madagascar.

Type material examined. Holotype male, MADAGASCAR: Diana Region: D.-S., Joffreville [-12.494, 49.207], 9.v.1958, F. Keiser (NMB). Paratypes. MADAGASCAR: Diana Region: 9 males, 10 females, same data as holotype (NMB).

Other material examined. MADAGASCAR: Sofia Region: 1 male, 1 female, Analalava, Sahamalaza Nat. Park [-14.21, 47.95], 24.vi–4.vii.2016, M.E. Irwin, R. Harin’Hala, Malaise in forest, 192 m (CSCA); 1 female, Ankarafa [-14.3858, 47.7575], 9–15.vii.2016, M.E. Irwin, R. Harin’Hala, Malaise, 180 m (CSCA).