Aka gwana sp. nov.

(Figs 3 A–C, 7A, 10)

Zoobank Registration: http://zoobank.org/ urn:lsid:zoobank.org:act:06E87AA3-58B5-4325-BCA5-A77F6C8B0F99

Types. Holotype, ♂, AUSTRALIA, Tas: Mt Michael, 710m, u.v.l., 24.x.1990 (T. Semmens) (TAIC 145562). Paratypes, 1 ♂, same data as holotype; 1 ♀, Mt Barrow summit, 1280m, UVL, 25.i.1990 (L. Hill) (TAIC).

Etymology. The term „ gwana “ means „goanna“ in Torres Strait Creole, an indigenous language spoken in Queensland (Thieberger & McGregor 1994). Named after the long, forked spine on the apex of flagellum which resembles the forked tongue of a goanna.

Diagnosis. This species can be distinguished from all other Australian Aka by the presence of more than two spines on the flagellum.

Colour. Vertex mid brown, carinae paler, with a whitish spot where subapical carinae meet lateral borders of vertex or vertex entirely light brown. Face light to mid brown, darker near vertex; carinae concolorous; frons often with a whitish spot at each lateral end of frontoclypeal suture. Pro- and mesonotum brown with slightly paler carinae; pronotum either paler than mesonotum or both the same colour but lateral parts darker. Forewings light brown to whitish, mottled with darker spots; veins concolorous with cells; tubercles darker, in distinct contrast to cells; pterostigma whitish. Abdominal sternites light brown. Legs light brown with a few darker marks.

Morphology. Body length: ♂ 4.2–4.3 mm; ♀ 5.1–5.6 mm.

Head: Vertex 1.3–1.4 x wider than long; median carina of vertex covering about 3/4 of basal compartment of vertex. Frons 1.2–1.3 x longer than wide; maximum width no more than 2x apical width; position of maximum width distinctly dorsad of centre of frontoclypeal suture; median carina forked in basal (near frontoclypeal suture) third to half of frons. Median ocellus present (indistinct). Anteclypeus with very indistinct median carina. Subapical segment of rostrum 1.3–1.7 x longer than apical segment.

Thorax: Mesonotum with indistinct sublateral carinae. Forewing 2.9–3.3 x longer than wide; costal margin with 8–11 distinct tubercles; tubercles aligned alongside veins, but reaching to some extent into cell area; tubercles large, dark, in distinct contrast to cells; many tubercles bearing very long setae; Sc+R+M near basal cell fused, forming a minute common stem Sc+R+M; fork of ScRA+ RP distinctly basad, slightly basad or at same level as fork CuA1+CuA2; distance tegula to ScR+M fork distinctly (about ½ to ¾) shorter than distance between this fork and ScRA+ RP fork; position of r-m moderately basad of fork MA+MP; fork MA+MP situated around apical 1/3 of forewing; icu slightly distad of apex of clavus; RP apically bifid; MA bifid; MP unforked; nodus of y-vein more or less in centre of clavus; y-vein with A1 moderately elevated; 7 apical cells. Hind leg: 1st tarsomere with 7 apical teeth; 2nd tarsomere with 7–8 apical teeth and 4–5 fine setae.

Male genitalia: Anal tube (Figs 10 C,D) apically slightly indented, forming two rounded lobes. Pygofer as in Fig. 10 E. Genital styles apically rounded, laterally produced resembling the beak of a bird as in Figs 10 F,G. Aedeagus (Figs 10 A,B): Phallotheca left laterally with spines (a,b) and right laterally with a curved spine (c). Base of phallotheca ventrally with 2 small sclerotised teeth. Flagellum near base with 3 sclerotised spines (d,e,f), apically widening into a large disc which gives rise to a long, bifurcate spine (g).

Remarks. In one of the specimens the CuA1+CuA2 fork is in an unusual position near the apex of the forewing, therefore the ScRA+ RP fork is distinctly basad in this specimen.