It has two broad leaves and a single narrow, greenish or reddish flower with a black, ant-like callus covering most of the upper surface of the labellum.

There is a glandular tip about 0.5 mm (0.02 in) long on the end of all three sepals.

The labellum is diamond-shaped, 7–10 mm (0.3–0.4 in) long and 6–7.5 mm (0.2–0.3 in) wide with a narrow, shiny black, ant-like callus covering most of its upper surface.

[2][3] Chiloglottis formicifera was first formally described in 1877 by Robert D. FitzGerald and the description was published in his book Australian Orchids from a specimen collected "in a gully at the Kurrajong".

[5]: 187 The common ant orchid grows in moist places in forest between the Northern Tablelands and Nowra.