Portulacaceae

Portulacaceae, commonly known as the purslane family, is a small family of flowering plants in the order Caryophyllales. The best-known genus is Portulaca, which includes the ornamental portulacas and the edible purslane Portulaca oleracea, widely cultivated as a leafy vegetable and common weed in warm regions. In modern classifications, the circumscription of Portulacaceae has become more restricted; many genera formerly placed in Portulacaceae have been reassigned to other families, notably Montiaceae and Anacampserotaceae, leaving Portulacaceae s.s. as a smaller group of primarily herbaceous species.

Description: Members are annual or perennial herbs, often with succulent leaves and stems. Leaves are usually simple, and the plants may be prostrate, ascending, or low shrubs in some genera. Flowers are small, bisexual, and typically pentamerous with five petals, often fused at the base; the floral parts are reduced and the ovary is often inferior. The fruit is a dry capsule that dehisces to release seeds.

Distribution and habitat: The family is distributed worldwide, with greatest diversity in arid and semi-arid regions. Portulaca species tolerate drought and poor soils, and some have become cosmopolitan weeds or cultivated crops.

Ecology and uses: Portulaca oleracea is edible and valued for its nutrition; other species are grown as ornamentals for ground cover and colorful displays. The family is of interest for studies of succulent adaptations and drought tolerance, reflecting its presence in hot, dry environments.

Taxonomy: Portulacaceae is placed in Caryophyllales, and its circumscription has changed with molecular data, leading to the transfer of several genera to related families. The type genus is Portulaca.