Calyceraceae

Calyceraceae is a small family of flowering plants in the order Asterales. In modern classifications it is recognized as a distinct family, though some systems have placed its genera within Asteraceae. The family is distributed mainly in the Southern Hemisphere, with representatives in South America and, to a lesser extent, other southern regions such as Australia. The members are typically herbaceous perennials or shrubs.

Morphology and characteristics commonly associated with Calyceraceae include simple, often alternate leaves and inflorescences that can be arranged in cymes or panicles. The flowers frequently display a prominent calyx-like involucre, a feature that contributes to the distinctive appearance of the group. The corolla, when present, tends to be reduced, and the fruit is usually a dry indehiscent type such as a nutlet or schizocarp. These floral traits distinguish Calyceraceae from many related groups within Asterales and have been of interest in studies of the evolution of inflorescence architecture in the order.

Ecology and habitat vary, but species commonly occupy open habitats such as grasslands, shrublands, or light woodlands. They are generally adapted to local pollinators and can be annual or perennial, depending on the species.

Taxonomy and phylogeny place Calyceraceae as a lineage within Asterales that is closely related to, and sometimes treated as, a separate family from Asteraceae. The name derives from the genus Calycera, reflecting the diagnostic calyx-like structures that characterize many of its members.