Megaselia hebblewhitei, DISNEY, 2003

DISNEY, R. H. L., 2003, Tasmanian Phoridae (Diptera) and some additional Australasian species, Journal of Natural History 37 (5), pp. 505-639 : 557-559

Megaselia hebblewhitei sp. nov.

(figure 24)

Material

H  : male, Tasmania, Fern Tree, near Hobart, Grays Road , at window of builder’s shed, 18 September 1998 ( R. H. L. Disney —25-23) ( TMH).

P    : 4 males, as holotype except some 22 September 1998 (25-28) ( UMZC).

Etymology

Named after John Hebblewhite, whose builder’s shed proved to be an excellent fly trap.

Diagnosis

The combination of scutellum with two small hairs and posterior pair of bristles; mesopleuron with small hairs and a bristle; costal index 0.39–0.45 (most <0.44); vein 3 forked; costal section 1>2+3, and 2>3; supra-antennal bristles unequal; and front basitarsus slender; takes this species to couplet 6 (of group III) on p. 205 of Borgmeier’s (1967a) keys. Or else, for those with costa>0.43, the combination of costal cilia 0.1 mm long; no differentiated anterodorsals on hind tibia; brown halteres; costa not thickened in middle of section 1; the single moderate bristle on mesopleuron; and costa <0.5; takes them to couplet 52 (of group II) on the same page. In group III its brown palps will immediately distinguish it from the yellow palped M. australiae Beyer , along with the hairs at rear of abdominal tergite 6 being subequal to those of epandrium, as opposed to being clearly longer. The subsequently described M. chlumetiae Disney runs to the same couplet, but it has the anal tube clearly longer than the epandrium, whereas it is plainly shorter in the new species. In group II the new species differs from M. moderata Borgmeier by having one (not two) bristles on the mesopleuron, a shorter anal tube and costal section 1 clearly longer than 2+3 (instead of being slightly shorter). Some M. bivesicata Schmitz will run to the same couplet, but the abdominal spiracles of its male are conspicuously enlarged. Other diagnostic features include 20–30 small SPS vesicles (at most as large as sockets of lower SAs) in third antennal segment; at least 20 small spinules below each labellum; brown thorax and abdominal tergites; three bristles on notopleuron; left lobe of hypandrium very short and bare distally; epandrium with hairs but no differentiated bristles; hairs of proctiger weak; all femora brown; hairs below basal half of hind femur longer than those of anteroventral row of distal half; neardorsal hair palisade of mid tibia extends about two-thirds of length; a minute hair at base of vein 3 (but one specimen with a larger, supernumerary, bristle as well).

Male

Frons brown, wider than long and with numerous, but very fine, microsetae. Antials level with upper SAs but nearer anterolaterals than to SAs, the ALs being a little higher on frons. Pre-ocellars a little closer together than either is from a mediolateral and usually a fraction lower on frons. Two or three bristles on cheek and likewise, but stronger ones, on jowl. Antennae brown. Palps paler with six or seven bristles of which three are stronger than rest. Orange-brown labrum at most 0.8× width of third antennal segment. Labella a little paler than labrum. Hairs of abdominal tergites small, but a little longer at rear of T 6. Venter brownish grey with hairs below segments 3–6. Hypopygium brown, with greyish anal tube, and as figure 24. Front tarsus with posterodorsal hair palisades on segments 1–4 only. Segment 5 subequal to, or slightly longer than, segment 4. Hind tibia with 14–18 differentiated, but not strong, posterodorsals. Wing 1.4–1.6 mm long. Costal ratios 3.36–3.71:1.18–1.34:1. Costal cilia 0.05–0.07 mm long. Two axillary bristles that are clearly longer than costal cilia. Sc ends before R. Veins pale brown, but 4–6 darker. 1

Membrane tinged pale greyish brown.