Sisyromyia angustivitta Li & Yeates 2019, sp. nov.
Creators: name: Li, Xuankun
name: Yeates, David K.
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Bombyliidae
Sisyromyia
Sisyromyia angustivitta

description: 2. Sisyromyia angustivitta sp. nov.
(Figs 2, 3)
Type specimens. Holotype ♂ Australia, WA, Albany, 5 Oct 1951 IFB Common. Paratype ♂ Australia, WA, same data as holotype.
Other specimen examined. Australia, WA, ♀ Stirling Rang Drive, Stirling Range Nat[ional] P[ar]k, 23 Sep 1981, ID Naumann & JC Cardale (WAM).
Diagnosis. Large-sized fly, body with mostly reddish hairs. Wing membrane brown. Abdominal tergites 2–7 with an inconspicuous narrow medial stripe consisting of sparse, decumbent short pale yellow scales.
Description. Male. Body length 11.9–12.0 mm, wing length 12.1–12.2 mm.
Head. Head about 2.3 x wider than long, mostly blackish with thick pale pruinescence and covered in admixed yellow to golden scales and brown to black hairs. Eyes holoptic. Frons short, 1.6 x length of ocellar tubercle, upper narrow and black; lower half triangular, as long as upper half, with sparse pale pruinescence and golden scales admixed with black hairs. Ocellar tubercle slightly raised, blackish brown to black with grey pruinescence, with black hairs admixed with few golden scales. Face with thick pale pruinescence and golden scales admixed with long black hairs, parafacial area without black hairs. Gena with thick pale pruinescence and long yellow scales. Clypeus with thick pale pruinescence and otherwise bare. Occiput with thick pale pruinescence and golden to reddish scales admixed with some black hairs. Posterior eye margin slightly convex. Antennal scape and pedicel black with sparse pale pruinescence, scape with long black hairs admixed with long golden scales, pedicel with short black hairs; flagellum black without pruinescence, subapex with 2–3 long hairs. Scape 2.4 x as long as wide, and 3.0 x as long as pedicel, uniform from base to apex. Pedicel as long as wide. Flagellum 12.0 x as long as wide, 2.3 x as long as scape + pedicel, 3.1 x as long as scape, conical and slightly laterally compressed, one-segmented with apical stylus, and with one long subapical hairs (Fig. 2c). Palpus long, just extending beyond oral cavity, yellow except apex brown, with pale yellow hairs except brown hairs apically, one-segmented, without palpal pit. Mouthparts slender, 3.9 x as long as eye length, 2.0 x as long as head length, labellum thin and filiform (Fig. 2h).
Thorax. Integumental colour of scutum mostly black with thick pale pruinescence. Scutum covered with short golden to reddish hairs admixed with few black hairs, some golden to reddish hairs turning brown apically. Scutellum brown with sparse pale pruinescence, with golden to reddish hairs admixed with few black hairs. Pleura black with thick pale pruinescence, mostly covered in long pale yellow hairs, except anepisternum with golden hairs admixed with few reddish hairs, anepimeron, meron, laterotergite and mediotergite bare.
Legs. Legs dark yellow. Femora with dense long yellow hairs and scales, admixed with few black hairs ventrally. Fore and mid femora with few anterior bristle on apical half; hind femur with one row of anteroventral bristles, and some separate bristles. Bristles and other hairs on legs brown. Fore tibia 2.4 x longer than fore basitarsus, mid tibia 2.7 x longer than mid basitarsus, hind tibia 2.7 x longer than hind basitarsus.
Wings. Wing membrane uniformly infuscated. Cell r 5 open, M 1 close to R 5; cell br nearly as long as cell bm, crossvein r-m arising from base of cell dm; crossvein m-m nearly as long as crossvein r-m; cell cup open (Fig. 2d). Haltere stem and knob yellow.
Abdomen. Integumental colour of tergites black mostly with sparse pale pruinescence. Tergite 1 with thick pale pruinescence and dense golden to reddish hairs; tergites 2–7 with long golden to reddish hairs, hairs near posterior margin of tergites turning reddish on apical half; tergites 2–7 with thin median stripe consisting of sparse, decumbent short pale yellow scales. Sternites black except posterior margin yellow, with thick pale pruinescence, covered with yellow hairs. Genitalia. Epandrium anterior margin slightly concave, posterior margin slightly convex (Fig. 3d). Lateral margin of gonocoxite strongly curved (Figs 3a,b); lateral ejaculatory process narrow; inner apex of gonocoxite long and sharp, outer apex of gonocoxite long and rounded; gap between inner apices of gonocoxites medium; phallus shorter than gonocoxite (Fig. 3c).
Female. Body length 12.0 mm, wing length 12.1 mm. Very similar to male, except frons black with sparse pale pruinescence, 3.0 x as wide as ocellar tubercle, frons with short golden scales admixed with long black hairs (Fig. 2l). Abdominal tergites with reddish scales and hairs, admixed with black hairs; median stripe wider than male. Around 30 acanthophorite spines present on each side of tergite 9+10 (Fig. 3g).
Remarks. Sisyromyia angustivitta sp. nov. is similar to Sisyromyia rutila, but the stripe on abdominal tergites 2–7 is narrow and inconspicuous, and the outer apex of gonocoxite is long.
Distribution. Australia (WA).
Etymology. The specific name refers to the inconspicuous narrow medial stripe on the abdominal tergites.
description: Published as part of Li, Xuankun & Yeates, David K., 2019, Revision of the Australian bee fly genus Sisyromyia White, 1916 (Bombyliidae, Bombyliinae, Acrophthalmydini), pp. 201-244 in Zootaxa 4711 (2) on pages 206-208, DOI: 10.11646/zootaxa.4711.2.1, http://zenodo.org/record/3576849