Hydrobiosella jirrima sp. nov.

Figures 14–16, 41

Holotype. Male. Victoria, McKay Ck, Sassafras Gap (about 36°37'S, 147°47'E), 2 Feb. 1974, A. Neboiss (NMV, T- 21438).

Paratypes. Victoria. 3 males (specimen CT-586 figured), collected with holotype; 5 males, 1 female (specimen CT-613 figured), Sassafras Gap, 13 Feb 1963, A. Neboiss ; 1 male, Gibbo R., S of Donovan Ck jn, 3 Feb 1974, A. Neboiss ; 1 male, roadside trickles, 1.2km N Sassafras Gap, lt tr., 11 Feb 2010, R. StClair and D. Cartwright (NMV) .

Diagnosis. Males of Hydrobiosella jirrima can be distinguished from those of other species in the group by the absence of a short dorsal ‘raised ridge’ subapically and slender apex on segment X.

Description. Wings similar to those of H. bandabanda (Fig. 1); length of forewing, male 6.6–7.8 mm, female 6.6 mm.

Male. Segment IX with a weak wide notch in meso-ventral margin (Fig. 16), and an almost rounded distal margin (Fig. 15). Segment X in dorsal view, a ‘tongue-shaped’ process, with almost parallel sides in basal quarter, with a pair of very small acute knobs baso-laterally, tapered distally to a narrow apex, without a central dorsal ridge or groove (Fig. 14); length about 1.9 times width; in lateral view weakly broad-based, tapered slightly in basal two thirds, very slightly bulbous apically (Fig. 15). Phallus generally tube-like, robust, with a pair of narrowly separated sub-apical spines (Figs 14, 15). Inferior appendages in lateral view, robust, with basal segment sub-rectangular, length about 2.3 times maximum width; harpago shorter, length about 0.6 times length basal segment, length about twice maximum width, with broad rounded apex (Fig. 15).

Female. Genitalia typical of genus, with a small projection on sternite IX meso-distally (Fig. 41).

Etymology. Jirrima – Australian aboriginal word for a mountain (type locality Sassafras Gap).

Remarks. Eleven males and one female of Hydrobiosella jirrima have been collected from three sites near the type locality in north-eastern Victoria (latitudinal range 36°37'- 36°39'S).