Prostrate perennial herbs, stellate-pubescent or with scales. Leaves simple, petiolate, crenate, stipulate. Flowers bisexual, solitary in axils; epicalyx (present in Victoria) of 3 linear lobes; pedicel not articulated; calyx lobed for about half its length; petals yellow, often with a reddish tinge, stellate-pubescent, not ciliate at base; stamens c. 50 or more; styles same number as carpels; stigmas capitate. Fruit a single ring of 6–10 readily splitting mericarps within persistent calyx, not with depressed central region; mericarps 1-seeded, same height as columella, reticulate laterally, smooth dorsally.
4 species, 3 in south-west USA and Mexico, 1 in Europe; 1 species naturalised in Australia (also naturalised in South America).
Malvella is distinguished from Sida in Australia by the presence of a 3-lobed epicalyx, by the stellate-pubescent corolla lobes and often by the capitate rather than discoid stigma of Australian Sida species. The epicalyx was present on all Australian material seen of Malvella leprosa but it can apparently be lacking in this and other members of the genus in other parts of the world (e.g. see Fryxell 1988).