Oxalidaceae
Oxalidaceae R.Br. comprises approximately 6 genera and 750–800 species, with the vast majority belonging to the genus Oxalis. Members are distributed worldwide, particularly in tropical and subtropical regions. Molecular phylogenetic studies support the monophyly of the family and have clarified relationships among its constituent genera. The family is characterized by herbaceous plants with compound leaves, pentamerous flowers, superior ovaries, and explosive capsular fruits.
Key characteristics
- Annual or perennial herbs
- Leaves alternate, usually trifoliolate
- Leaflets heart-shaped and often fold at night
- Flowers actinomorphic, five-merous
- Ten stamens
- Superior ovary
- Fruit a loculicidal capsule with explosive seed dispersal
- Plants rich in oxalic acid
Distribution
Oxalidaceae has a nearly cosmopolitan distribution, with greatest diversity in South America, southern Africa, tropical America, and parts of Asia. Members occur in forests, grasslands, rocky slopes, wetlands, cultivated fields, gardens, and disturbed habitats, from sea level to alpine regions. In Pakistan, Oxalidaceae occurs, the Potohar Plateau, Salt Range, and Himalayan regions. Species are commonly found in lawns, gardens, agricultural fields, orchards, roadsides, forest margins, moist grasslands, and cultivated lands, especially during winter and spring.