Gnathifera robinsoni sp. nov.

(Figs 13, 29)

Type material. Holotype: ♂ New South Wales: “ CSIRO Exp. Fm., Wilton, N. S. W., 6.4.1972, [leg.] V. J. Robinson;” “Gen.präp. [genitalia slide] Gaedike Nr. 9165;” “ Holotypus ♂, Gnathifera robinsoni sp. n., det. R. Gaedike 2018;” ANIC.

Description. (Fig. 13). Wingspan 11 mm.

Head pale cream-coloured, scales on neck with white tips; labial palpus externally cream-coloured, internally nearly white; antenna with pecten, flagellum ringed.

Thorax and tegulae also cream-coloured, tips of thorax and tegulae white; forewing narrow, with creamcoloured ground-colour, a pattern partly rubbed off, visible only as brown smaller patches near base above dorsum and at 1/4 below costa; a minute dark brown dot at the end of cell and at apex; hindwing light grey.

Male genitalia (Fig. 29). Uncus straight, with rounded tip, gnathos broad, apically rounded, with numerous minute bristles; juxta U-shaped, the arms apically edged inwards with pointed tip; valval ventral and costal margins parallel, ventral edge 3/4 of the length of costal edge, then curved and narrowed to apex with two short bristled lobes, a rod-shaped sclerotization below the second lobe; phallus nearly two times longer than valva, straight, apex arrow-tip-shaped.

Female genitalia. Unknown.

Diagnosis. As the pattern of forewing is partly rubbed off, the new species externally is hard to distinguish from the other members of the genus. Clear differences are seen in the genitalia structure: the U-shaped juxta and the arrow-shaped tip of phallus are unique characters among the species belonging to the acacivorella species group.

Distribution. New South Wales.

Bionomics. The early stages and host plants are unknown.

Etymology. This species is named in honour of the collector, V. J. Robinson.