Chiloglottis sphaerula is a species of orchid endemic to a small part of New South Wales. It has two dark green leaves and a single green to reddish pink flower with a shiny black insect-like callus covering two-thirds of the base of the labellum but with the tip of the labellum free of callus.
Chiloglottis sphaerula is a terrestrial, perennial, deciduous, herb with two egg-shaped leaves NaNsigfig=2NaNsigfig=2 long and NaNsigfig=1NaNsigfig=1 wide on a petiole NaNsigfig=1NaNsigfig=1 long. A single green to reddish pink flower NaNsigfig=1NaNsigfig=1 long is borne on a flowering stem NaNsigfig=1NaNsigfig=1 high. The dorsal sepal is spatula-shaped, to egg-shaped with the narrower end towards the base, NaNsigfig=2NaNsigfig=2 long and NaNsigfig=2NaNsigfig=2 wide. The lateral sepals are linear, NaNsigfig=1NaNsigfig=1 long, about 1.5sigfig=1NaNsigfig=1 wide, erect near their bases but turn downwards and away from each other. There is a glandular tip about 2sigfig=1NaNsigfig=1 long on the end of the dorsal sepal and NaNsigfig=1NaNsigfig=1 long on the lateral sepals. The petals are narrow egg-shaped with the narrower end towards the base, NaNsigfig=1NaNsigfig=1 long, about 4sigfig=1NaNsigfig=1 wide and turn downwards near the ovary. The labellum is wedge-shaped to trowel-shaped, NaNsigfig=1NaNsigfig=1 long and about 8sigfig=1NaNsigfig=1 wide. There is a shiny black, insect-like callus about 2sigfig=1NaNsigfig=1 long and 2.5sigfig=1NaNsigfig=1 wide, occupying two-thirds of the labellum base. The large callus is surrounded by many dark reddish, club-shaped calli up to 2sigfig=1NaNsigfig=1 long and by smaller calli near its base. The remaining one-third of the tip of the labellum is devoid of calli. The column is pale green with reddish flecks, NaNsigfig=2NaNsigfig=2 long and about 4sigfig=1NaNsigfig=1 wide with narrow wings. Flowering occurs from December to February.[1]
Chiloglottis sphaerula was first formally described in 2006 by David Jones from a specimen collected in the Barrington Tops National Park and the description was published in Australian Orchid Research.[2] The specific epithet (sphaerula) is a Latin word meaning "ball"[3] referring to the shape of the "head" of the insect-like callus.
This species was formerly known as Chiloglottis sp. aff. sphyrnoides (Northern Tablelands).[4]
This orchid grows in tall, moist forest on the southern part of the Northern Tablelands and Barrington Tops National Park.