Megaselia digiturgida, Disney, 2008

Disney, R. H. L., 2008, Six new species of Megaselia Rondani (Diptera: Phoridae) from mainland Australia, Zootaxa 1899 (1), pp. 57-68 : 59-60

Megaselia digiturgida sp. nov.

( Figs 2–4 )

In the keys of Borgmeier (1967b) this will run to couplet 79, on page 90, where neither lead applies. The modified fifth tarsal segments on the middle and hind legs and the hypopygium will distinguish it from similar species.

The name refers to the swollen fifth tarsal segments on the middle and hind legs.

Male. Frons brown, clearly broader than long, with 54–56 hairs and dense but very fine microsetae. SAs unequal, the lower pair being shorter. The antials level with or slightly lower on frons than upper SAs and a little lower than ALs; and at least twice as far from an upper SA as either is from an AL bristle. Pre-ocellars distinctly further apart than either is from a mediolateral bristle, which is a little higher on frons. Cheek with 4 bristles and jowl with two that are longer and more robust. The subglobose postpedicels dusky straw yellow and without subcutaneous pit sensilla (SPS) vesicles. Palps straw yellow, at most a quarter the width of a postpedicel, with 5 bristles and 7–8 hairs. Labrum almost colourless and at most 0.9x as wide as a postpedicel. Labella coloured as palps and with only a few short spinules below. Thorax orange brown on top shading to straw yellow on sides (apart from brown patch on pteropleuron). Three notopleural bristles and no cleft in front of these. Mesopleuron bare. Scutellum with an anterior pair of hairs (at most as long as those at rear of scutum) and a posterior pair of bristles. Abdominal tergites with T1, the rear third of T2, most of T3 and much of T4 brown and the rest yellow. The hairs are strongest towards the sides of T2, posterolaterally on T3–T5 and at rear of T6 ( Fig. 4 ). Venter whitish yellow, and with hairs on segments 3–6, those at the rear of 6 below being more bristle-like ( Fig. 4 ). Hypopygium with a brown epandrium, a mainly straw yellow hypandrium and a paler anal tube, and as Fig. 4 . The right hypandrial lobe clearly shorter than the left lobe. Legs straw yellow apart from brown patch on the mid coxae and the light brown fifth tarsal segments of the middle and hind legs. Fore tarsus with posterodorsal hair palisade on segments 1–5 and 5 not quite as long as 4. Dorsal hair palisade of mid tibia extends about 0.7x its length. Fifth tarsal segment swollen and clearly longer than fourth ( Fig. 2 ). Hairs below basal half of hind femur longer than those of anteroventral row of outer half. Hind tibia with 16 differentiated posterodorsal hairs and spinules of apical combs simple. Fifth tarsal segment expanded distally ( Fig. 3 ). Wings 1.6 mm long. Costal index 0.52–0.53. Costal ratios 4.6–4.6: 3.6–3.7: 1. Costal cilia (of section 3) 0.06 mm long. No hair at base of vein 3. With two axillary bristles, the outer being longer than costal cilia. Sc not quite reaching R1. Thick veins yellowish brown, thin veins 4–6 dark grey and 7 paler, but faint in basal half. Membrane lightly tinged brownish grey (just evident to naked eye when viewed against a white background). Haltere knob brown.

Material. Holotype male, Australia, New South Wales, Tweed Heads, 10 The Quarterdeck , garden, water trap, 30 June 2008, R. H. L. Disney ( AMS, 25–61).

Figures

FIGURES 2–4. Megaselia digiturgida male: (2) mid tarsus, segments 3–5; (3) hind tarsus, segments 3–5; (4) left face of hypopygium. Scale bar = 0.1 mm.