Acianthus pusillus
Small Mosquito OrchidFlowering plant 4–18 cm tall. Leaf cordate, thin, 15–30 mm long, 12–25 mm wide, green above, reddish-purple (rarely greenish) beneath, entire or sometimes shallowly lobed. Flowers 1–18, translucent green or pinkish with reddish veins and spots, labellum green to reddish-purple; pedicel (including ovary) 4–6 mm long, subtended by small bract; dorsal sepal hooded, linear-obovate, 5–8 mm long, apical point c. 1–2 mm long; lateral sepals projected obliquely forwards, parallel, crossed or divergent, linear to linear-oblanceolate with fine point, similar in length to dorsal sepal; petals spreading or reflexed, linear-ovate to ovate, c. 3 mm long. Labellum on short claw, slightly decurved distally, oblong-ovate to ovate-lanceolate, 3–5 mm long, 2–3 mm wide; base of lamina broadly wedge-shaped or squarish with rounded corners, margins revolute, entire, apex with short point; callus thick, fleshy, smooth or slightly papillose towards the apex. Column incurved, almost terete, not winged. Flowers Apr.–Aug.
Wim, GleP, VVP, GipP, OtP, WaP, Gold, CVU, GGr, DunT, NIS, EGL, EGU, WPro, HSF, HNF, OtR, Strz. Also SA, Qld, NSW, Tas. Widespread, but mainly in the southern part of the State, from coastal scrub to inland woodland and forests.
Differs from the less common A. exsertus in being not as robust, with a more slender inflorescence bearing smaller, dull-coloured flowers. The labellum of A. pusillus is always shorter than that of A. exsertus, and is less truncate at the base.
Entwisle, T.J. (1994). Orchidaceae. In: Walsh, N.G.; Entwisle, T.J., Flora of Victoria Vol. 2, Ferns and Allied Plants, Conifers and Monocotyledons, pp. 740–901. Inkata Press, Melbourne.
