Borboroides donaldi, McAlpine, 2007

McAlpine, DK, 2007, Review of the Borboroidini or Wombat Flies (Diptera: Heteromyzidae), with Reconsideration of the Status of Families Heleomyzidae and Sphaeroceridae, and Descriptions of Femoral Gland-baskets, Records of the Australian Museum 59, pp. 143-219 : 173-175

Borboroides donaldi n.sp.

Figs 37, 56–60

Material examined. HOLOTYPE.?, New South Wales : Mount Wilson [Blue Mountains; Waterfall Reserve, c. 900 m, 33°31'S 150°23'E], 6–7.v.2002, D.K.M. ( AM K219747 ). Mounted on card point . PARATYPES. New South Wales : 1?, same data as holotype ( AM) ; 8??, 1!, Kanangra Road , 14.2 km S of Oberon – Jenolan road junction, April 2002, B.J.D. ( AM, ANIC, USNM) ; 1?, Boyd River crossing, Kanangra-Boyd National Park, April 2004, D.K.M. ( AM) ; 4??, Black Springs fossicking area, Vulcan State Forest, c. 27 km SSW of Oberon, May 2003, B.J.D. ( AM) ; 1!, 2 mi. [c. 3 km] SW of Tumorrama [ Tumut district ], June 1964, G.L.B. ( AM) ; 3!!, Kunama [Batlow district], Aug. 1961, D.H.C. ( AM, ANIC) ; 1?, Clyde Mountain , west slope, May 1965, Z.R.L. ( ANIC) ; 6? Mongarlowe River , Clyde Mountain, May 1965, D.H.C. ( ANIC) ; 5??, 1!, 5 mi. [c. 8 km] S of Monga [ Braidwood District ], May 1968, D.H.C., Z.R.L. ( ANIC) . Australian Capital Territory : 15??, 3!!, Bull’s Head, April, Oct. 1960 –1972, D.H.C., D.K.M. ( AM, ANIC) ; 29??, 1!, Mount Coree, April 1968, D.H.C. ( AM, ANIC) ; 1!, Tidbinbilla , Aug. 1972, D.K.M. ( AM) ; 1?, Honeysuckle Creek , Aug. 1985, I.D.N., J.C.C. ( ANIC) .

Other material. (localities only given). Victoria: Frenchman’s Gap, near Woods Point, 3,500 ft [c. 1,070 m] ( AM); 13 mi. [c. 21 km] W of Matlock ( AM, MV); Mount Donna Buang, near Warburton ( AM).

Description (male, female). Rather small, partly darkcoloured, partly shining fly, somewhat resembling B. musica and B. stewarti , agreeing with description given for latter, except as indicated.

Coloration. Prelabrum yellow, often darker tawny brown, in female; palpus brown. thorax largely black to blackish brown (unfaded specimens); mesoscutum with lateral zone, including part of humeral callus and notopleuron, tawny brown, often with indication of tawny-brown dorsocentral mark or line (more obvious in faded specimens); pleura with tawny stripe on propleuron, lower part of mesopleuron, upper margin of sternopleuron, and often smaller zone on hypopleuron; pleura generally pruinescent, except for large bare, glossy zone covering central and anteroventral parts of mesopleuron, but not reaching fore-coxal foramen. Legs of male yellowish to tawny, with all femora and tarsi distally browned to variable extent; legs of female usually more extensively browned. Abdomen largely black to dark brown; male with tawny areas on tergites 4 and 5, parts of sternite 8 and posterior part of epandrium; female with entire preabdomen black (unfaded specimens); tergite 4 bare and glossy; tergite 5 densely grey- to brown-pruinescent, with small shining black zone on each lateral extremity.

Head. Eye subcircular, usually not higher than long; height of cheek 0.44–0.57 of height of eye; anterior fronto-orbital bristle sloped outwards and usually very slightly reclinate, c. half as long as posterior fronto-orbital or slightly more. Antenna: segment 3 of male not as large as in B. stewarti , distinctly more elongate than in female.

Thorax. Mesoscutum c. as wide as long in female, slightly narrower in male; intradorsocentral setulae in one paramedian pair of rows, not reaching posteriorly to level of posterior dorsocentral bristle, at most few setulae between these and dorsocentral lines; middle dorsocentral bristle at least slightly shorter than anterior one, sometimes much reduced. Legs: mid femur without posteroventral bristles in either sex; hind femur of male with single series of fine, inconspicuous posteroventral bristles and no posteroventral excavation; mid tibia with mid-ventral subapical spur large in female, small or scarcely differentiated in male; hind tibia of male almost straight, not particularly attenuated basally. Wing: subcosta weakly sclerotized distally, its junction with costa not easily visible; veins 2 and 3 slightly diverging distally; apical section of vein 4 1.8–2.3× as long as penultimate section.

Abdomen. In male tergites and sternites 4 and 5 with moderately developed setulae only; sternite 5 medially attenuated rather than divided; in female tergite 5 much shorter than tergite 4, capable of withdrawal and concealment below tergite 4. Male postabdomen: protandrium resembling that of B. musica but more slender; epandrium broadly inflated, approximately symmetrical, with no transverse ridge on anteroventral bridge, except that which borders on anterior foramen; surstylus of simple form, much longer than broad, compressed, not incurved, with few setulae, some quite long, and two or three much thicker long setulae on inner surface towards apex; prehypandrial membrane invaginated behind the unusually extensive anteroventral bridge, thus not readily externally visible; gonite anteriorly prominent, with numerous long setulae having attenuated tips; basiphallus broad, with pair of almost membranous anterior lamellae and incurved lateral wings; distiphallus on anterior surface with scale-like roughening, many of the processes acute; distal part of distiphallus rounded, flexed forwards; cerci short, moderately broad, approximated on median line, withdrawn and largely concealed in most views by epandrium and surstyli, each with some setulae on distal margin less developed than B. musica , and bulbous densely setulose sea-urchin-like anterior extension, setulae of latter with simple bases (unlike corresponding anterior setulae of B. musica ). Female postabdomen somewhat resembling that of B. stewarti .

Dimensions. Total length,? 1.7–2.5 mm,! 2.6–3.2 mm; length of thorax,? 0.75–1.1 mm,! 1.2–1.4 mm; length of wing,? 2.3–3.3 mm,! 3.5–4.2 mm.

Distribution. New South Wales: cooler districts, from Blue Mountains southwards. Australian Capital Territory: Canberra district. Eastern Victoria.

Notes

Borboroides donaldi belongs in the stewarti group, with which it agrees in venation and setulosity of the mesoscutum. It is distinguishable from B. stewarti and B. musica by the much darker thorax. Males are distinguishable from the dark-coloured B. lindsayae and B. tonnoiri by the absence of a ventral brush of long mollisetae on the mid tibia, and females differ from these two species in the large, strongly shining tergite 4 with lateral submarginal groove and relatively small tergite 5. Borboroides donaldi differs from all other species of the stewarti group in having a very large central glossy zone on the mesopleuron. As usual the male postabdominal characters are distinctive, but the invagination of the prehypandrial membrane, so that it is concealed in anteroventral view, occurs also in B. lindsayae and B. tonnoiri .

Borboroides donaldi has been collected around wombat dung bait on several occasions.

The specific epithet refers to Donald H. Colless, whose extensive collections of Borboroides (in ANIC) form a major basis for this study.