Austrothaumalea bifida, Sinclair, 2008

Sinclair, Bradley J., 2008, New Species of Austrothaumalea Tonnoir from Australia (Diptera: Thaumaleidae), Records of the Australian Museum 60 (1), pp. 1-12 : 4-6

Austrothaumalea bifida n.sp.

Fig. 3

Type material. HOLOTYPE? “AUST: N.QLD: Mt. /Elliot N.P., 600 m /above Alligator Ck. /Falls, 9.iv.1994; seep / B.J. Sinclair ”; “ HOLOTYPE / Austrothaumalea /bifida /Sinclair [dissected]” ( AMS) . PARATYPES: Queensland: 1?, 5 !!, same data as holotype ( AMS) .

Recognition. This species is distinguished by the bifid gonostylus and forked apex of the paramere.

Description. Wing length 1.7–2.0 mm. Coloration: Head dull, dark brown. Mesonotum and pleura dark brown and somewhat shiny; coxae, femora and tibiae pale brown, tarsi darker; halter knob pale on inner margin; abdomen dull greyish-brown, including pleural membrane; terminalia generally dark. Wing faintly infuscate; R+R 1 +R 1+2 with macrotrichia along entire length, remaining veins bare; R 2 situated towards apex of R 1; bend in R 3 gentle, not strongly defined; R 3 and R 4+5 divergent toward wing margin; CuA with short basal appendage. Male abdominal sternite 1, narrow, spectacle-shaped; sternite 2 reduced to slender, median sclerite, with pair of small, posterolateral sclerites; sternites 3–6 rectangular, sparsely setose; sternite 7 narrow, one-half length of sternite 6; sternite 8 reduced to Y-shaped sickle. Male terminalia ( Fig. 3 ): Epandrium broadly triangular from ventral aspect; posterior margin narrow, evenly rounded; lacking pointed posterolateral processes. Hypandrium broad, less than width of base of gonostylus. Gonocoxite long, slightly expanded apically. Gonostylus mitten-shaped; thumb-like appendage short, truncate; apical process tapering and lacking setulae. Parameres fused to form long tube, arching dorsally, with abrupt subapical bend directly posteriorly; apex broadly forked (holotype) or sickle-shaped (paratype); extending beyond epandrium. Gonocoxal plate broad; apical margin concave, generally very pale; not fused to hypandrium.

Distribution. This species was collected from the same site as A. bicornis , south of Townsville, Queensland.

Etymology. The specific name is from the Latin bifidus (bifurcated), referring to the apex of the paramere.

Remarks. This species appears to be closely related to A. cervulus and A. uptoni on the basis of their bifid gonostylus and truncate gonocoxal plate. The apex of the paramere of A. bifidus differs between the holotype (forked) and paratype (sickle-shaped) ( Fig. 3 ), a similar variation in the apex of the paramere was also noted in A. commoni ( Theischinger, 1986, figs 25–26).

Figures

Figs 1–4. Male terminalia of Austrothaumalea: (1) A. bicornis, lateral view; (2) A. bicornis, ventral view; (3) A. bifida, ventral view (holotype), tip of paramere from paratype; (4) A. concava, ventral view. Scale bar = 0.1 mm. Abbreviations: epand, epandrium; gcx, gonocoxite; gcx pl, gonocoxal plate; gst, gonostylus; hypd, hypandrium; pm, paramere.