About Cyrtostylis rotundifolia Hook.f.
Cyrtostylis rotundifolia Hook.f. is a terrestrial, perennial, deciduous herb. It produces a single leaf that is kidney-shaped, egg-shaped, heart-shaped or almost round, measuring 10–40 mm (0.4–2 in) long and 8–17 mm (0.3–0.7 in) wide. Up to four pink or pinkish green flowers, each 8–10 mm (0.3–0.4 in) long, grow on a thin flowering stem that reaches up to 100 mm (4 in) in height. The dorsal sepal is erect, and ranges from linear to narrow lance-shaped. The lateral sepals are narrow linear and somewhat smaller than the dorsal sepal. Petals are similar in size and shape to the lateral sepals. The labellum is flat and oval, about 10 mm (0.4 in) long and 4 mm (0.16 in) wide, with two round calli at its base and two parallel longitudinal ridges. The column is shorter than the labellum, and has two wings that widen toward the tip. Flowering occurs between June and October. This species is very similar to Cyrtostylis oblonga, and the status of these two species requires further investigation. Compared to C. oblonga, which has yellowish green, oblong leaves, C. rotundifolia has grey-green, mostly egg-shaped leaves. This winter orchid grows in lightly shaded scrub and open areas in the southern half of the North Island and the lower two-thirds of the South Island of New Zealand.
