Gondwanamyia Sinclair, Cumming, Brooks, Plant & Saigusa

Sinclair, Bradley J., Cumming, Jeffrey M., Brooks, Scott E., Plant, Adrian R. & Saigusa, Toyohei, 2016, Gondwanamyia, a new empidoid (Diptera) genus of uncertain placement, ZooKeys 621, pp. 137-147 : 138-140

Taxon classification Animalia Diptera Empididae

Gondwanamyia Sinclair, Cumming, Brooks, Plant & Saigusa gen. n.

Type-species.

Gondwanamyia chilensis Cumming & Saigusa, sp. n.

Diagnosis.

Body size minute, 1.1-1.4 mm. Arista-like stylus very long, longer than thorax, lacking basal article; males and females dichoptic, eye facets convex, appearing larger than in other empidoids; clypeus strongly convex; mouthparts with large epipharyngeal carina and paired epipharyngeal blades; wing with weakened fold near base, only two longitudinal veins fully developed (R4+5 and M4), R4+5 branched; abdomen with abdominal plaques; male terminalia symmetrical and unrotated, epandrium and hypandrium desclerotized and fused together, epandrial lobe and cercus projected anterodorsally, phallus tubular with or without an elongate apical filament, ejaculatory apodeme slender, rod-like; female terminalia sclerotized, sclerites beyond segment 6 mostly bare; tergite and sternite 8 anteroventrally articulated; female cercus sclerotized, projecting horizontally.

Description.

Male.Head: Dichoptic; eye facets convex; some short scattered ommatrichia. Antenna with scape reduced, strap-like with several setulae; pedicel globular, slightly shorter than postpedicel; arista-like stylus longer than thorax, lacking basal article. Ocellar triangle small, not raised, with stout ocellar setae inserted anteriorly, opposite anterior ocellus; several setulae posterior to ocellar triangle; vertical seta lateroclinate; 1 shorter seta between vertical seta and ocellar triangle; several postocular setae present. Mouthparts with swollen or inflated clypeus; epipharyngeal carina elongate and slender, extended well into clypeal region; epipharyngeal blades present at apex of carina, slender and pointed apically; labrum thickly sclerotized laterally; hypopharynx slender, stylet-like; lacinia apparently absent; palpus oval, flattened on inner face, with several long setulae; labellum pointed apically, narrow, without pseudotracheae, apical margin with series of peg-like sensilla.

Thorax: Chaetotaxy well developed and in distinct rows; acrostichals present or absent. Prosternum separated between fore coxae. Dorsal mesepimeral pocket present; metasternal furca tapered to narrow apex, lacking apical projections. Laterotergite bare. Fore leg simple, not raptorial; tibia without basal gland. Mid femur with row of stout posteroventral setae. Hind tibia with posteroapical comb.

Wing: Length: 1.1-1.5 mm. Cuneate and narrowed at base, slightly infuscate; anal lobe and alula not developed. Costa circumambient with basal costal seta and several subequal setae proximal to R1; slender, erect costal setae widely distributed to beyond R4; costal break distal to Sc, continuing posteriorly as weakened transverse fold across cell bm; costa with second break at R1; R1 very short, terminating in basal 0.25 of wing; R2+3 very short, nearly vertical, terminating at apex of R1; two longitudinal veins fully developed (R4+5 and M4); R4+5 branched, with R4 nearly perpendicular to R5; M4 nearly straight, slightly arched toward wing margin; cell dm absent; cell bm quadrate; cell br longer than cell bm; cell cua weakly open parallel to wing margin. Halter long, subequal in length to scutum; shaft with several basal setulae; knob tapered apically.

Abdomen: Abdominal tergites and sternites without modifications, sparsely setose; abdominal plaques present; tergite 8 slender, strap-like; sternite 8 expanded laterally to cradle terminalia, thinly sclerotized medioventrally; posterior marginal setae on sternite 8 distinct and well defined.

Male terminalia: Upright, symmetrical and unrotated; epandrium and hypandrium desclerotized and fused together; gonocoxal apodeme slender, rod-shaped; cercus well developed; phallus tubular with or without elongate apical filament, ejaculatory apodeme slender.

Female terminalia: Sclerotized, mostly bare; tergite 8 shallowly notched posteromedially with four posteromarginal setae; tergite and sternite 8 anteroventrally articulated; tergite ten subtriangular, not divided medially with one pair of posterolateral and one pair of apical setae, apical setae closely approximated; sternite ten triangular, pigmented laterally with pair of lateral setae; cercus thickly sclerotized, similar to sclerite 10, with apex bearing pair of long, stout setae; spermatheca thread-like, extending full length of abdomen.

Etymology.

Named after the southern Mesozoic continent of Gondwana, in reference to the probable age and distribution of this genus of flies on the southern continents of South America and Australasia (Figs 10, 11). All five authors are responsible for the new genus name. TS first identified this new genus, and both ARP and JMC + BJS independently studied separate series. SEB recently discovered the New Zealand species.