Annual herbs, branched mostly at base, all parts usually stiffly hairy. Leaves opposite at first in a basal rosette, subsessile, sheathing, upper ones alternate, distant, sessile. Inflorescences terminal, of 1 or 2 erect scorpioid cymes; bracts present. Flowers pedicellate; sepals 5, slightly connate basally, scarcely elongating after flowering; corolla regular, 5-lobed, cylindric, blue, scales in throat papillose; stamens included just below throat of corolla-tube, anthers ovoid, subsessile, appendages short and acute; ovary 4-lobed, 4-celled, pyramidal, style short, inserted near middle of ovary, stigma capitate. Fruit breaking into 4 mericarps leaving a slender, conical gynobase; mericarps ovoid, finely hairy, outer surface flattened and immersed below marginal rim, rim with few stout, barbed spines of varying length.
A monotypic genus endemic to Australia where widespread.