Lyperanthus R. Br.

Description.—Terrestrial, glabrous herbs with ovoid or globose tubers. Leaves 1–3, basal or cauline. Flowers 1–8 in a terminal raceme. Dorsal sepal incurved, cumulate, deflexed. Lateral sepals as long as the dorsal, narrower, erect or spreading. Petals similar. Labellum much shorter, sessile, 3–lobed at the base, more or less papillose, the lamina often with ridged calli. Column incurved, about as long as the labellum, obscurely winged. Stigma orbicular, high on the column. Rostellum prominent, between stigma and anther. Anther terminal, erect or horizontal, 2-celled. Pollinia 2–4 Pollen granular or mealy.

1. Lyperanthus antarcticus Hook. f., Fl. Ant., 2, 1847, 544.

Orch. No. 8, Hook, f., Fl Ant., 1, 1844, 71.

Up to 37 cm. high. Leaves up to 3, sessile, cauline, linear- to oblong-lanceolate, coriaceous, acute. Floral bracts large, sheathing, acuminate. Upper flower with a subulate lobe (an undeveloped flower-bud—similar vestiges occur in Adenochilus and in Corybas) at the anterior base of the ovary. Flowers up to 4, greenish with dark chocolate blotches. Dorsal sepal horizontal broad-cumulate, apiculate. Lateral sepals linear-acuminate, as long as the dorsal. Petals similar. Labellum pale green, ovate, subacute, margins turned outwards. Lamina vaguely ridged with pale linear calli. Column incurved, narrowly winged at the top, the wings with small tuberculate lobes extending behind the anther. Column spotted with pink towards the top. Stigma and rostellum raised on a short thick pedicel. Anther horizontal. Pollinia 4, subterete. Pollen granular.

Distribution.—Endemic—7, frequent above 3,000 ft. in the Tararua Ranges; 9, 10, 11, 12a, 13, 15, subalpine areas throughout, not common; 16, “Stewart Is., T. Kirk, Freshwater River, 1, 1947, C. Smith. Also in the Auckland Islands.

Flowers December-February. Sea-level-4,000 ft., subalpine scrub or forest margins, descending to sea-level in the outlying islands.