It has a single thin, more or less hollow, onion-like leaf and up to fifty small yellowish-green and red flowers.

The plants grow in winter-wet areas, often in shallow water and unlike the similar M. cupularis do not turn black as they dry.

[2][3][4][5] The dark mignonette orchid was first formally described in 1907 by Richard Sanders Rogers from a specimen collected from a swamp near Myponga.

The specific epithet (orbicularis) is a Latin word meaning "orbicular" or "having the form of a small circle", referring to the shape of the labellum.

[2][8] Microtis orbicularis grows in swamps and seasonally wet depressions, sometimes with the base of the plant submerged.