Victorian Naturalist 127: 57 (2010) APNI
Threat status:Victoria: endangered (e)
Flowering plant to 12 cm tall, stem leaves 4–6, closely sheathing. Rosette leaves 5–9, elliptic, 0.5–1.5 cm long, 3–8 mm wide, shortly petiolate to nearly sessile, crowded, margins entire. Flowers 3–12, crowded, 6–8 mm long, yellowish green with darker green lines; galea curved throughout, suddenly decurved near the apex; dorsal sepal acute; lateral sepals deflexed, conjoined part broadly ovate in outline when flattened, 3–4 mm long, 4–5 mm wide, margins incurved, concave, free points broadly triangular, c. 2 mm long, parallel; petals asymmetrical, broadest near the base, obtuse. Labellum pale green with a dark green basal appendage; lamina obovate-oblong, c. 2 mm long, c. 1.6 mm wide; appendage c. 1.3 mm long, with a prominent central beak pointing forward. Flowers Oct.–Nov.
Endemic to Victoria where found in stony rise basalt plains grasslands near Mortlake, on heavy red-brown loam.
Pterostylis spissa is critically endangered and known from very plants in a small roadside reserve.