Distribution of Acanthaceae:
It is commonly known as Acanthus family. It includes 250 genera and 2500 species. The family is chiefly distributed in tropics and sub-tropics. In India 508 species are present.
Economic Importance of Acanthaceae:
- Medicinal: Many plants of the family are medicinal. Adhatoda vasika and Barleria cristata are used in cough. Roots of Rhinanthus, Ruellia are also used in medicine. Roots of Ecbolium are used in jaundice. Andrographic paniculata is used for liver diseases. Fruits and leaves of Phlogacanthus thyrsiflorus are used for fever. Leaves of Phlogacanthus tubiflorus when rubbed in water yields lather which is used like soap for washing purposes.
- Ornamental: Many plants are cultivated for ornamental purposes viz., Acanthus, Barleria, Justicia, Thunbergia, Jacobinia, Ruellia, are often used as hedge.
Affinities of Acanthaceae:
There seems to be agreement among botanist to retain the Acanthaceae as a distinct family. It has been derived from Scrophulariaceae or stocks ancestral to the Scrophulariaceae. Bessey placed it at the top of his Scrophulariales. But the Acanthaceae differs from the Scrophulariaceae in having bracteate and bracteolate flowers, imbricate sepals of unequal length; loculicidal capsule and non-endospermic seeds with jaculators. It is closely related to the Lamiaceae, but distinguished by a number of characters e.g. absence of aromatic smell, typically quadriangular stem, verticellaster inflorescence, gynobasic style, quadrilocular ovary. These are present in the Lamiaceae.