Hydrobiosella fibra sp. nov.

Figures 18–20

Holotype. Male. Queensland, Kenilworth rainforest (about 26°36'S, 152°44'E), 7 Apr. 1967, N. Dobrotworsky (NMV, T- 21450).

Paratypes. Queensland. 2 males, collected with holotype (specimen PT-578 figured) (NMV) .

Diagnosis. Males of Hydrobiosella fibra can be separated from other species in the group by the presence of a pair of stout baso-lateral lobes on tergum X.

Description. Wings similar to H. letti (Fig. 17); length of forewing, male 6.3-6.6 mm.

Male. Segment IX in lateral view, sub-quadrate, length about 1.8-1.9 times width, projecting slightly basally (Fig. 6.3), with a shallow rounded notch medially on distal margin (Fig. 20). Segment X with a pair of large sub-ovate baso-lateral lobes (Figs 18, 19); in dorsal view, ‘tongue-shaped (fig. 18); in lateral view slender, slightly tapered distally (Fig. 19). Phallus generally tube-like, with a pair of straight, slender lateral ‘parameres’ arising basally (Figs 18, 19). Inferior appendages in lateral view, with basal segment sub-rectangular, length about 1.7-1.8 times maximum width; harpago slightly shorter, length about 1.6 times maximum width; bulbous dorso-basally, tapered slightly distally, broadly rounded apically (Fig. 19).

Female. Unknown.

Etymology. Fibra – Latin for lobe (on tergum X).

Remarks. Three male specimens of Hydrobiosella fibra have been collected from the type locality in south-eastern Queensland (latitude 26°36'S).