Flowering plant to 15–40 cm high, stem leaves 8–15, spreading to ascending, ovate-lanceolate, 2–6 cm long, 6–12 mm wide, dark green. Rosette leaves on a separate plant, 5–10, ovate, 10–40 mm long, 5–15 mm wide. Flowers 1–15, semi-nodding, 14–20 mm long, 10–15 mm wide, dark reddish-brown or nearly black with transparent areas in the galea; dorsal sepal with a short apical point; lateral sepals deflexed, conjoined part broadly ovate, 11–14 mm long, 12–14 mm wide, mostly flat, concave beneath the labellum, free point c. 5 mm long, tapered; petals slightly falcate, with a well-developed proximal flange. Labellum oblong-ovate, 5.5–6.5 mm long, 3.5–4 mm wide, dark reddish-brown to blackish, basal mound with an erect, tail-like appendage c. 1 mm long. Flowers Jun.–Sep.
LoM, MuM, Wim, GleP, VVP, GipP, OtP, Gold, CVU, GGr, DunT, WPro, Strz. Also WA, SA, Tas. Of disjunct occurrence west from Yarram and as far inland as the Grampians, in open forest and woodland, mostly on well-drained sandy soils.
Plants from the Little and Big Deserts, closely resembling Pterostylis sanguinea, but generally smaller, paler and fewer-flowered have been separated out as a distinct species, Pterostylis arbuscula (D.L.Jones & C.J.French) D.L.Jones & C.J.French, but the characters purportedly distinguishing the two species are inconclusive in relation to Victorian species. It is also recorded from WA and SA, but pending further evidence of its distinctness, P. arbuscula is here treated as a synonym.
