Borboroides dayi, 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 : 178-179

Borboroides dayi n.sp.

Figs 64–69

Material examined. HOLOTYPE.?, New South Wales : Boyd River crossing, Kanangra-Boyd National Park, 13.iv.2004, D.K.M. ( AM K219748 ). Mounted on card point . PARATYPES. New South Wales : 1?, same data as holotype ( AM) ; 3!!, Mount Wilson , Blue Mountains, April, Sept. 2002 –2005, D.K.M. ( AM) ; 2??, Sawpit Creek , Snowy Mountains, Feb. 1979, D.K.M., B.J.D. ( AM) . Australian Capital Territory : 1?, Gibraltar Creek, Jan. 1978, Z.R.L. ( ANIC) .

Other material. Victoria: 3??, near Mount Juliet, 9 km E of Healesville, April 2003, B.J.D., D.K.M. ( AM, MV); 3??, 15!!, lower reservoir, Falls Creek , Trawool, Jan. 2005, D.R.B. ( AM, ANIC, MV) .

Description (male, female). Very small, largely black fly, with unmarked wings, very similar to B. staniochi and agreeing with description of that species, except as indicated below.

Coloration. Postfrons with tawny-orange anterior margin, elsewhere almost entirely grey-pruinescent, apparently with fingerprint sculpture less developed than in B. staniochi ; face and cheek region largely tawny-yellow in male, generally much darker in female. Prelabrum tawny to brown in male, brown to black in female. Mesoscutum more denselybrown- pruinescent than in B. staniochi ; mesopleuron very extensively grey-brown- pruinescent, with glossy zone narrow, restricted to anteroventral part but widely separated from margin of fore-coxal foramen.

Head. Height of cheek 0.26–0.30 of height of eye; anterior fronto-orbital bristle reclinate, c. half as long as posterior one or slightly less. Prelabrum of female broad, moderately deep and prominent, smaller in male.

Thorax. Intradorsocentral setulae in six to eight irregular rows; one large posterior sternopleural bristle present and two or three large setulae in front of it. Hind femur with anterodorsal bristle often indistinct; fore and hind tibiae each with distinct but not large preapical dorsal bristle; mid tibia with two longitudinally aligned anterodorsal bristles before level of preapical dorsal pair, the more distal one larger, proximal one rarely absent (as in smallest male), also with the following subapical spurs in both sexes: large anterior, large ventral, moderately large posterior one; hind tibia with apical anteroventral spur very small, but stouter than adjacent setulae. Wing: apical section of vein 4 c. 3.2–3.5 times as long as penultimate section; distal section of vein 5 straight or almost so; distal section of vein 6 extending c. 0.75–0.80 of distance from anal crossvein to margin.

Abdomen. In male, tergite 5 distinctly smaller than tergite 4; sternite 5 much shorter than tergite 5, not medially narrowed, posteromedially with group of mostly short, slightly spinescent setulae, with a series of longer setulae laterally. Male postabdomen: tergite 6 absent; spiracles 6 and 7 present on both sides; sternite 6 (anterior part of protandrial synsternite) with dark, strongly sclerotized anterior band encircling postabdomen, ventrally glabrous, but with little pruinescence between median ventral part and sternite 7; sternite 7 rather small, compact, glabrous, lateroventral in position; sternite 8 shorter and stouter than in B. staniochi , subconical, sclerotized and pruinescent all round, except for posteroventral bight, with few stout posterodorsal and posterolateral setulae, and pair of lateroventral setulae near mid-length; epandrium rather large and stout, narrowed at anterior extremity, extensively coarsely setulose, with welldeveloped anteroventral bridge; surstylus rather broad basally but without posterobasal foot, evenly tapered to narrowly obtuse apex, with few setulae mainly on anterior and distal surfaces, with only two to four small spinules restricted to inner surface at apex; gonite large, subcylindrical, setulose, without sub-basal gibbosity; aedeagus moderately short, stoutly tongue-shaped, its cuticle with many fine sclerotized ridges which are dense and parallel towards base, apically and anteriorly with fine hispid microtrichia, with posterior section of smooth, transparent, inflatable cuticle; basiphallus without processes; aedeagal apodeme long and rather stout; cerci quite small, obovoid, separate but approximated to each other, remote from bases of surstyli, each with few long setulae.

Dimensions. Total length,? 1.6–2.0 mm,! 1.5 mm; length of thorax,? 0.72–0.94 mm,! 0.84 mm; length of wing,? 1.5–1.8 mm,! 1.8 mm.

Distribution. New South Wales: Central and Southern Tablelands divisions. Australian Capital Territory: Canberra district. Victoria: Yarra Valley and Seymour district.

Notes

Borboroides dayi is most similar to B. staniochi as indicated in the key to species. The main differentiating characters are given under that species.

Compared with B. staniochi , B. dayi has a wide distribution, but is known from cooler habitats. Most specimens have been collected at wombat dung bait, and probably all are from natural wombat habitats.

The specific epithet refers to Barry J. Day, who has done much collecting for this project.