Nematoceras sulcatum

Nematoceras sulcatum
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Monocots
Order:	Asparagales
Family:	Orchidaceae
Subfamily:	Orchidoideae
Tribe:	Diurideae
Subtribe:	Acianthinae
Genus:	Nematoceras
Species:	N. sulcatum
Binomial name
Nematoceras sulcatum M.A.Clem. et D.L.Jones

Nematoceras sulcatum, also known as the Grooved Helmet-orchid, is one of two helmet orchids endemic to Australia’s subantarctic Macquarie Island, and the second to be discovered. The specific epithet comes from the Latin sulcatus – “grooved”, with reference to the prominent groove in the labellum boss. It is a small, terrestrial, tuberous, herbaceous plant that forms clonal colonies. The flower is erect, mostly dark red, 25–30 mm long and 10–14 mm wide. The flowering period is November–December. It occurs on the plateau uplands of the island, growing in wet grassy seepage areas. It can be distinguished from its congener, and the only other orchid on the island Nematoceras dienemum, by its dark red flowers.

Conservation status

Macquarie Island is a nature reserve, a World Heritage Site and a UNESCO Biosphere Reserve. However, the orchid is listed as endangered on the Tasmanian Threatened Species Protection Act 1995 because of its restricted distribution, small population (estimated in 2010 to comprise fewer than 250 mature individual plants), and projected decline through ongoing habitat degradation caused by the grazing, digging and burrowing activities of rabbits.