Thomasia is a genus of thirty-one species of flowering plants in the family Malvaceae. Plants in this genus are small shrubs that are endemic to the south-west of Western Australia, apart from T. petalocalyx that is native to Victoria and South Australia. The leaves are simple with leaf-like stipules at the base of the petiole, the flowers bisexual with five papery, petal-like sepals, usually five petals and five stamens opposite the petals. The fruit is a capsule covered with star-like hairs.

Taxonomy

The genus Thomasia was first formally described in 1821 by Jaques Étienne Gay in Mémoires du Muséum d'Histoire Naturelle. The name Thomasia honours Pierre Thomas, his son Abraham, and Abraham's sons Philippe, Louis and Emmanuel, a family of Swiss plant collectors.

Species list

The following is a listed of Thomasia species recognised by the Australian Plant Census as at December 2020: