Diuris unica

Diuris unica is a species of orchid which is endemic to eastern Australia. It usually has only one grass-like leaf at its base and up to eight bright, lemon-yellow flowers with a few dark markings. It is similar to D. chrysantha but flowers much earlier than that species and has only a single leaf rather than two.

Description
Diuris unica is a tuberous, perennial herb with a single, linear leaf, 150-280 mm long, 3-7 mm wide and folded lengthwise. Up to eight flowers 18-25 mm wide are borne on a flowering stem 150-450 mm tall. The flowers are bright lemon-yellow with a few dark markings at the base of the dorsal sepal and labellum. The dorsal sepal curves upwards and is egg-shaped, 7-10 mm long and 5-7 mm wide. The lateral sepals are egg-shaped to spatula-shaped with the narrower end towards the base, 8-18 mm long, 2-3 mm wide, held below the horizontal and parallel to each other or crossed. The petals are erect with an elliptical to almost round blade, 5-8 mm long and wide on a blackish stalk 4-5 mm long. The labellum is 7-9 mm long and has three lobes. The centre lobe is egg-shaped to wedge-shaped, 6-8 mm long, 5-8 mm wide and the side lobes are oblong to broadly wedge-shaped, 3-4 mm long and about 2 mm wide. There are two thick, ridge-like calli 4-5 mm long in the mid-line of the base of the labellum. Flowering occurs from July to September.

Taxonomy and naming
Diuris unica was first formally described in 2006 by David Jones from a specimen he collected near Maryborough in 1986. The specific epithet (unica) is a Latin word meaning "only", "sole" or "singular", referring to the single leaf of this orchid.

Distribution and habitat
This orchid grows in wallum and sandy heath in coastal and near-coastal districts in south-eastern Queensland and disjunctly in northern New South Wales.