Megaselia falsoluta, Disney, R. Henry L., 2006

Disney, R. Henry L., 2006, Nine new species of Megaselia Rondani (Diptera: Phoridae) from the Seychelles, Zootaxa 1210, pp. 1-25 : 7-9

Megaselia falsoluta sp. nov.

( Figs 6–7 )

Aphiochaeta soluta Collin, 1912 , under “Note 2”.

Collin in his Note 2 under Aphiochaeta soluta commented “there is probably yet another species near soluta in the collection, but I refrain from naming it....”. I have remounted the specimen labelled “see Note 2” in the CUMZ and found it to be this species, which I had already recognised amongst the recently collected material. It is currently only known in the male sex.

In the keys of Beyer (1965) this species runs to triplet 19 on pages 49–50, where it runs out as M. androidea Bridarolli , but the latter has darker brown legs and a shorter costa. The omitted species M. soluta Collin also runs to this triplet and, unaccountably, Beyer omitted M. bispatulata Bridarolli as well. The male of the latter is distinguished from the other two by the numerous (>12) hairs, in addition to a differentiated bristle, on the left side of the epandrium. M. soluta and the new species closely resemble each other. Apart from small differences in the hypopygia, they are most readily distinguished by the size of labella in the males and by the arrangement of the frontal bristles. The new species has the antials close to the ALs, which are about level with upper SAs but clearly closer to the eye margins than to the antials, which are a little lower than the upper SAs. M. soluta has the antials almost equidistant from upper SAs and ALs, which are distinctly higher on frons and only slightly closer to the eye margins than to antials, which are level with or slightly lower than upper SAs. The labella of the male in the new species are clearly larger than those of M. soluta . The next species belongs to the same complex, but is readily distinguished from M. soluta and M. falsoluta by the possession of bifid spinules in the apical comb of the hind tibia.

Male

Frons brown, clearly broader than long, with 48–64 hairs, with dense but very fine microsetae and the bristles arranged as Fig. 6 . SAs robust but lower pair shorter and weaker. Cheek with 3–5 bristles and jowl with two longer ones. Postpedicels subglobose, light brown but appearing darker because of dense pubescence, without SPS. Palps pale straw yellow, with five moderate and two small bristles and 6–8 hairs. Labrum a little darker than palps and about 0.7–0.8x as wide as postpedicel. Labella a little darker on top, about 0.8–0.9x as wide as postpedicel (so the two together are clearly broader than latter), and with numerous crowded short spinules below. Thorax brown, being paler on sides. Mesopleuron with 5–13 hairs and 1–3 (usually 2) bristles at hind margin. Three notopleural bristles and no cleft in front of these. Scutellum with an anterior pair of hairs (subequal to those in middle of scutum) and a posterior pair of bristles. Abdominal tergites brown with well developed hairs, and those at rear of T6 clearly longer than rest ( Fig. 7 ). Venter greyish brown, and with conspicuous hairs below segments 3–6. Hypopygium brown, with straw yellow anal tube, and as Fig. 7 . Right lobe of hypandrium vestigial. With two rectal papillae. Legs with coxae, femora and dorsal edge of hind tibia yellowish brown to brown, the rest being straw yellow. Fore tarsus with posterodorsal hair palisade on segments 1–5. Dorsal hair palisade of mid tibia extends about three quarters of length. Hairs below basal half of hind femur a little longer than those of anteroventral row of outer half. Hind tibia with 10–12 differentiated posterodorsal hairs, the lowest seven being robust but the last is not stronger than the rest. Spinules of apical combs simple. Wings 1.2–1.5 mm long. Costal index 0.49–0.52. Costal ratios 2.9–4.2: 2.5–3.3: 1. Costal cilia (of section 3) 0.10–0.12 mm long. Hair at base of vein 3 longer than costal cilia at level of humeral cross vein. With 2–3 axillary bristles, the outer being shorter than costal cilia. Sc not reaching R1. Veins yellowish brown to brown. Membrane tinged brownish grey (just evident to naked eye when viewed against a white background). Haltere with brown stem and yellow knob.

Material

HOLOTYPE male, Seychelles, Silhouette Island, Jardin Marron, 2000–2001, J. Gerlach ( CUMZ, 8­133). Paratypes, 3 males, as holotype ( CUMZ, 133, 141, 142); 4 males, Lantana, Lantana North, Malaise trap, 30 July to 1 August 2000, J. Gerlach ( CUMZ, 8­122­124). 1 male (remounted on a slide), Mahé, 1908–1909 (see Note 2, 120, CUMZ, 8­134).

Figures

FIGURES 6, 7. Megaselia falsoluta, male: (6) frons, with bristles represented by their basal sockets only; (7) left face of hypopygium. Scale bars = 0.1 mm.