[1] The current number of species by genus (reported in 2002) is as follows: Forstera - 5, Levenhookia - 10, Oreostylidium - 1, Phyllachne - 4, and Stylidium - 221.

[2] Stylidium rotundifolium appeared in Joseph Banks' Florilegium (plate 173), drawn from a specimen collected at Endeavour River, Australia in 1770.

The APG II system recommends its inclusion in Stylidiaceae but allows for the optional recognition of the family Donatiaceae.

The subfamilies were created to distinguish the difference between the five typical genera of the Stylidiaceae from the single genus Donatia, which Mildbraed placed in Donatioideae.

[6] This level of infraspecific taxonomy is not used in recent research, but the groupings are supported by molecular data that suggest Forstera and Phyllachne are closely related but distinct from the other three.