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

description: 12. Dissodesma binghi (Evenhuis, 1989) comb. nov.
(Figs 26–28)
Bombylius brevirostris Macquart, 1850: 423 (119). Type locality: “ Tasmanie ” [error, probably = Australia (NSW)] [H in MNHN]. [Preoccupied by Olivier, 1789.]
Systoechus eulabiatus Bigot, 1892: 366. Type locality: “Van-Diémen” [= Australia (Tas.)] [H in UNKN].
Sisyromyia binghi Evenhuis, 1989: 364 (new replacement name for Bombylius brevirostris Macquart, 1850).
breverostris, incorrect original spelling of brevirostris (Macquart, 1840: pl. 7, fig. 7 [1841: pl. 7, fig. 7]).
Type specimen. Holotype of Bombylius brevirostris Macquart, ♀ (MNHN ED9271) (Fig. 24).
Other specimen examined. Australia, ACT, ♂ Gibraltar Peak, 9 Sep 1948. NSW, ♂ 5mi. S. Mendooran, 18 Mar 1972. G Daniels. ♂ (2) ♀ (3), Gundamain, Port Hacking, National Park, 1 Mar 1926, Mackerras. SA, ♀ Black Hill, near Montacute, Adelaide, 6 Mar 1949, HF Lower. Tas., ♀ Freycinet Nat [ional] P[ar]k, 28 Feb 1963, IFB Common & MS Upton.
Redescription. Male. Body length 7.0– 9.6 mm, wing length 7.3–10.0 mm.
Head. Head about 2.0 x wider than long, mostly blackish with thick white pruinescence and covered in admixed white to pale yellow scales and hairs. Eyes holoptic. Frons long, 3.6 x length of ocellar tubercle, upper narrow and black; lower half triangular, 1.6 x length of upper half, with thick pale pruinescence and pale yellow hairs. Ocellar tubercle slightly raised, blackish brown to black with grey pruinescence, with long pale yellow hairs. Face with thick white pruinescence and long pale yellow scales, parafacial area with white scales. Gena with thick white pruinescence and long white hairs. Clypeus with thick pale pruinescence and otherwise bare. Occiput with thick white pruinescence and dense pale yellow scales. Posterior eye margin slightly concave. Antennal scape and pedicel black, scape with thick pale pruinescence and long pale yellow hairs, pedicel with sparse pale pruinescence and short pale yellow hairs; flagellum black without pruinescence. Scape 3.3 x as long as wide, and 3.6 x as long as pedicel, uniform from base to apex. Pedicel 1.1 x as long as wide. Flagellum 10.4 x as long as wide, 1.5 x as long as scape + pedicel, 1.9 x as long as scape, conical and slightly laterally compressed, one-segmented with apical stylus (Fig. 25c). Palpus short, not extending beyond oral cavity, yellow with short black hairs, one-segmented, without palpal pit. Mouthparts slender, 3.9 x as long as eye length, 2.2 x as long as head length, labellum thin and filiform (Fig. 25h).
Thorax. Integumental colour of scutum mostly black with thick grey pruinescence. Scutum covered with pale yellow hairs admixed with few black hairs near posterior margin, pale yellow hairs darker apically. Three yellow notopleural setae present. Scutellum black with sparse pale pruinescence, covered with long yellow hairs, posterior margin admixed with some strong black hairs. Pleura black with thick pale pruinescence, mostly covered in long pale yellow hairs, except anepimeron, meron, laterotergite and mediotergite bare.
Legs. Legs mostly blackish brown except fore and mid femora dark yellow apically, fore and mid tibiae yellow. Femora covered in pale yellow scales, ventral face with long pale yellow hairs. Hind femur with one row of anteroventral yellow bristles. Mid and fore tibiae covered in pale yellow scales, anterior face admixed with some brown scales. Other bristles and hairs on legs brownish yellow. Fore tibia 1.7 x longer than fore basitarsus, mid tibia 2.4 x longer than mid basitarsus, hind tibia 2.2 x longer than hind basitarsus.
Wings. Wing membrane slightly infuscated, darker towards wing base and along costa. Cell r 5 narrowly open; 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. 25d). Haltere stem yellow, knob pale yellow.
Abdomen. Integumental colour of tergites black mostly with sparse grey pruinescence. Tergite 1 with dense yellow hairs; tergites 2 to 4, and 7 to 8 with yellow hairs, admixed few long black hairs laterally and on posterior margin; tergites 5 and 6 admixed with dense long black hairs laterally. Sternites black except posterior margin yellow, with thick pale pruinescence, covered with pale yellow scales and hairs. Genitalia. Epandrium wide and short, anterior margin nearly straight, posterior margin strongly concave (Fig. 26d). Hypandrium present. Gonocoxal apex with slightly narrower than the base in dorsal view, ejaculatory apodeme small (Figs 26 ab); gonocoxal apodeme strong and incurved; lateral ejaculatory process strong; inner apex of gonocoxite acute, slender and elongate; outer apex of gonocoxite acute, normal length; dorsal bridge with lateral hollow; gonostylus normal; phallus strong, as long as gonocoxite (Fig. 26c).
Female. Body length 5.2–8.4 mm, wing length 5.5–9.0 mm. Very similar to male, except frons black with thick pale pruinescence, 3.0 x as wide as ocellar tubercle, frons with short white to pale yellow scales on lower half, long pale yellow hairs on upper half, admixed with some long black hairs (Fig. 25k). Tergite 8 with thick hairs, 6 acanthophorite spines present on each side of tergite 9+10, slightly curved apically. Genital fork slender and straight, connect at apex. Sperm pump strong and long, with some lateral papillae; distal spermathecal duct of normal length, thickened in apical half; spermatheca small and nearly spherical, apex rounded (Fig. 26g).
Remarks. Systoechus eulabiatus was first proposed as a junior synonym of Bombylius brevirostris by White (1916), and followed by Roberts (1928), but it was not followed by Evenhuis & Greathead (1999).
The holotype of B. brevirostris was identified and examined by the senior author during his visit to MNHN, found in a very bad condition (Fig. 24). This holotype was examined by Evenhuis & Greathead (1999), but without a type label when Li visited MNHN in Sep 2018. The holotype was re-identified by Li, who added the holotype label and a label stating “ Holotype identified by Xuankun Li Sep 2018 ” (Fig. 24).
The deposition of the holotype of S. eulabiatus is unknown, and we have not located it. By comparing the specimens from NSW and Tas., we agree with the arrangement by White (1916), and treat S. eulabiatus as a synonym of B. brevirostris.
B. brevirostris was included in Sisyromyia when the genus was established (White, 1916), but the name was subsequently replaced by Sisyromyia binghi Evenhuis, 1989 due to preoccupation.
Based on the genitalia characters of both male and female, this species belongs to the genus Dissodesma Bowden & Li, 2018 (Li and Yeates, 2018). Therefore, Dissodesma binghi is a new combination proposed in the present study.
Distribution. Australia (ACT, NSW, SA, Tas.).
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 239-240, DOI: 10.11646/zootaxa.4711.2.1, http://zenodo.org/record/3576849