Megaselia wellingtonensis, DISNEY, 2003

DISNEY, R. H. L., 2003, Tasmanian Phoridae (Diptera) and some additional Australasian species, Journal of Natural History 37 (5), pp. 505-639 : 592-593

Megaselia wellingtonensis sp. nov.

(figure 45C)

Material

H  : male, Tasmania, Mount Wellington, 1270 m, 30 December 1991 ( R. H. L. Disney —25-6 ( TMH).

Etymology The name refers to the type locality.

Diagnosis

The combination of scutellum with anterior pair of small hairs (shorter than those at rear of scutum) and posterior pair of bristles; five to seven small hairs on mesopleuron; and costal index 0.41; places this species in group V of Borgmeier’s (1967a) keys. Couplet 1 of this key is an error, as M. curtineura (Brues) has a bare mesopleuron and therefore does not belong to group V. The brown haltere takes M. wellingtonensis to lead 1 of couplet 2 but the costal ratios of 2.48:1.30:1 take it to lead 2. The anal tube is about twice as long as that of M. turbidipennis Borgmeier and the details of the hypopygium will further distinguish it from M. arctifurca Borgmeier. Other diagnostic features are the lack of differentiated anterodorsal hairs on hind tibia; vestigial posterior lobes of hypandrium; no hair at base of vein 3; near-dorsal hair palisade of mid tibia extending about 0.7× its length; hairs below basal half of hind femur weaker and shorter than those of anterovental row of outer half; front basitarsus stout and with ventral rows of small spinules and a differentiated row of anteroventral hairs; anal tube shorter than midline length of epandrium; left side of epandrium with differentiated bristle in anterior half and more than nine hairs.

Male

Frons brown, broader than long, with numerous fine microsetae, and 58–60 hairs. Lower supra-antennal bristles robust and about 0.9× as long as upper pair. Antials closer to anterolaterals than to upper SAs and about level with latter. ALs a little higher on frons. Bristles of middle row almost equally spaced and in almost straight transverse row. With two to three bristles on cheek and two or three on jowl. Third antennal segment brown and without SPS vesicles. Palp brown with six subequal bristles that are longer than its greatest breadth, and half as many hairs. Brown labrum only about 0.6× as wide as third antennal segment. Whitish yellow, narrow labella tinged brown above and with only a few spinules below. Thorax brown and with three bristles on notopleuron. Abdominal tergites brown with short hairs that are only a little longer at rear of T 6. Venter greyish brown and with hairs below segments 3–6. Hypopygium brown and as figure 45C. Legs entirely brown. Posterodorsal hair palisade on fore-tarsal segments 1–4 only and 5 distinctly longer than 4. A dozen differentiated posterodorsal hairs on hind tibia. Wings 1.2–1.3 mm long. Costal cilia 0.08–0.09 mm long. Vein Sc ending before reaching R. Three 1

bristles on axillary ridge, of which at least the outer two are slightly longer than costal cilia. Veins light brown, but 7 only a faint shadow. Membrane lightly tinged brownish grey.