Genoplesium tenellum is a species of small terrestrial orchid that is endemic to eastern Australia. It has a single leaf fused to the flowering stem and between 5 and 21 green flowers with reddish-purple lines and markings.
Genoplesium tenellum is a terrestrial, perennial, deciduous, herb with an underground tuber and a single cylindrical leaf long, sheathing the flowering stem with the free part long and about wide. Between 5 and 21 green flowers with reddish-purple lines and markings are arranged along a flowering stem long. The flowers are long and about wide. As with others in the genus, the flowers are inverted so that the labellum is above the column rather than below it. The dorsal sepal is narrowly egg-shaped and forms a hood over the column, about long, wide and pale green with red lines and markings. The lateral sepals are linear, long, about wide, and spread apart with a slightly swollen base. The petals are narrowly egg-shaped, long and about wide with red edges and a red stripe along the centre. The labellum is egg-shaped with the narrower end towards the base, about long and wide with reddish-purple hairs. There is a purple callus covering the base of the labellum and extending nearly to its tip. Flowering has been observed from Late January to late May.[1]
This species of orchid was first formally described in 2013 by David Jones and Lachlan Copeland who gave it the name Corunastylis tenella in The Orchadian from specimens Copeland collected near Inverell in 2004.[2] In 2016, Julian Shaw changed the name to Genoplesium tenellum in the Quarterly Supplement to the International Register of Orchid Hybrids (Sander's List)[3] [4] and the name is accepted by Plants of the World Online. The specific epithet (tenellum) means "delicate' or "dainty", referring to the habit and appearance of this species.
Genoplesium tenellum grows in woodland with shrubs and scattered trees around the edges of granite outcrops at altitudes of . It is only known from near Torrington in northern New South Wales and Stanthorpe in far south-eastern Queensland.