Zygophyllaceae

Zygophyllaceae, the caltrop family, is a family of flowering plants in the order Zygophyllales. It comprises about 25–28 genera and approximately 260–290 species. The group is widespread in warm, arid and semi-arid regions of Africa, Asia, the Americas, and Australia. In modern classifications such as APG IV, Zygophyllaceae is treated as a distinct family, while Nitrariaceae is recognized as a separate family within the same order.

Most members are shrubs, subshrubs, or sometimes small trees; some are herbaceous. Leaves are usually opposite and simple or pinnate with two leaflets; stipules may be present. Flowers are typically small and actinomorphic, with five petals. The ovaries are usually superior, and the fruit is commonly a dry capsule that dehisces to release seeds. Some taxa bear spines or other adaptations to desert environments.

Prominent genera include Zygophyllum, Tribulus, Fagonia, Tetraena, and Larrea. Tribulus terrestris, widely known as puncture vine, is one of the best-known species and is used in traditional medicine and as an ornamental plant in dry landscapes.

The family is adapted to hot, dry habitats and can play roles in soil stabilization and forage in arid zones. Several species have traditional medicinal uses; others are valued as ornamentals or for drought tolerance in landscaping. As with many desert plants, conservation status varies by species and region.