Stenanthemum leucophractum is a soft, spreading shrub or subshrub that typically grows to a height of 25–40 cm (9.8–15.7 in), its branchlets covered with woolly, rust-coloured hairs.

The flowers are white or yellowish, and arranged in sessile heads 5–10 mm (0.20–0.39 in) wide, surrounded by small brown bracts and 2 or more whitish, felt-like floral leaves.

Flowering occurs from September to December, and the fruit is an oval capsule 2.0–3.0 mm (0.079–0.118 in) long.

[2][3][4][5][6] Stenanthemum leucophractum was first formally described in 1847 by Diederich Franz Leonhard von Schlechtendal who gave it the name Cryptandra leucophracta in the journal Linnaea.

[9] Rusty poison grows in mallee and is found in north-western Victoria, including in the Little Desert National Park, from the Eyre Peninsula to Kangaroo Island in South Australia, and between the Ardlethan and Hillston districts of inland New South Wales.