Platysace cirrosa, commonly known as karna, is a twining, perennial herb or climber that is endemic to the south-west of Western Australia.

[2] It is leafless, sometimes with a few very small scale-like leaves, and flowers arranged in umbels with overlapping yellow petals and flattened fruit.

Platysace cirrosa is a twining, tuberous, perennial herb or climber, that is usually leafless or with very small, tapering scale-like leaves.

The flowers are arranged on the ends of branches in compound umbels with a few small, narrow involucral bracts and blunt, yellow, overlapping petals.

[7] This platysace is found along slopes and drainage lines in the Avon Wheatbelt, Geraldton Sandplains, Jarrah Forest and Yalgoo bioregions of south-western Western Australia where it grows in lateritic or loamy soils over granite.