Chiloglottis trilabra, commonly known as the long-clubbed wasp orchid, is a species of orchid endemic to south-eastern Australia. It has two dark green leaves and a single greenish brown or pinkish flower with a dark red to black, ant-like callus covering most of the upper surface of the labellum. It is similar to both C. seminuda and C. reflexa.
Chiloglottis trilabra is a terrestrial, perennial, deciduous, herb with two dark green, oblong to egg-shaped leaves NaNsigfig=1NaNsigfig=1 long and NaNsigfig=1NaNsigfig=1 wide. A single greenish brown or pinkish flower NaNsigfig=2NaNsigfig=2 long and NaNsigfig=1NaNsigfig=1 wide is borne on a flowering stem NaNsigfig=1NaNsigfig=1 high. The dorsal sepal is spatula-shaped, NaNsigfig=1NaNsigfig=1 long and NaNsigfig=1NaNsigfig=1 wide. The lateral sepals are linear, NaNsigfig=1NaNsigfig=1 long, less than 1sigfig=1NaNsigfig=1 wide and curve downwards. There is a glandular tip NaNsigfig=1NaNsigfig=1 long on the dorsal sepal, dark red and NaNsigfig=1NaNsigfig=1 long on the lateral sepals. The petals are oblong to lance-shaped, NaNsigfig=2NaNsigfig=2 long, about 3sigfig=1NaNsigfig=1 wide and turned downwards towards the ovary. The labellum is more or less horizontal, diamond-shaped, NaNsigfig=2NaNsigfig=2 long and NaNsigfig=1NaNsigfig=1 wide with a black, ant-like callus surrounded by many stalked and stalkless glands occupying most of its upper surface. The column has narrow wings. Flowering occurs from December to March.[1] [2] [3]
This wasp orchid is similar to C. seminuda which has a callus covering only about two-thirds of the labellum. It is also similar to C. reflexa but has longer lateral sepals and a smaller "head" on the ant-like callus.[4]
Chiloglottis trilabra was first formally described in 1883 by Robert D. FitzGerald and the description was published in Journal of Botany, British and Foreign from a specimen "obtained on Mount York in the Blue Mountains".[5] [6] The specific epithet (trilabra) is derived from the Latin prefix tri- meaning "three"[7] and labra meaning "lip". The type specimen happened to be an aberrant form having two extra labellums in place of two lateral sepals.[8]
The long-clubbed wasp orchid is widespread in moist parts of forest, mainly on the ranges in New South Wales. In Victoria it is only known from a few areas in the east, but may be more widespread because it has been confused with C. seminuda and C. reflexa.