Spiranthes australis

Detailed description

Terrestrial, glabrescent, somewhat fleshy, perennial herb. Plant at flowering up to 1 m tall. Roots stilt-like, numerous, white, more or less swollen, clustered around stem base. Tuber broadly ovoid to ellipsoid. Stem erect, slender to stout, initially rather brittle, becoming wiry. greatly exceeding leaves. Basal leaves 2–10, obliquely erect, held in a loose basal rosette; lamina 50–200 × 5–15 mm; dark green to yellow green, often tinged reddish, narrow-elliptic, narrow-lanceolate, to lanceolate or almost spathulate tapering into a 20–100 mm long petiole; stem-bracts 2–4–(6). Inflorescence spicate. Spike 20–150 × 5–10 mm; flowers more or less crowded, subsessile, spirally around stem. Ovary glabrescent to finely glandular pubescent. Perianth 4–7 mm long, more or less tubular-cylindric, rose-pink, rose-red, red, pink or completely white. Dorsal sepal projecting forwards, column-embracing, more or less oblong, slightly concave except near the upturned apex. Lateral sepals divergent, slightly pouched at base, obtuse to subacute. Petals projected forwards, more or less oblong, more or less fused to dorsal sepal with their apices recurved. Labellum white or whitish pink with a white apex, broad and recurved at apex, more or less obscurely trilobed; mid-lobe upper margin more or less finely laciniate, much crisped, irregularly thickened; base sessile, concave, smooth, except for two prominent ovoid, lateral calli which fit beneath the stigma. Column narrow below stigma; anther obtuse, overtopping stigma; stigma broad and prominent, sometimes lacking rostellum, usually overtopped by delicate, membranous, laciniate column-wings.