S. I. Ali & Brian Mathew

Iris aitchisonii Credit: B. Mathew

Perennial herbs with rhizomes, corms or bulbs. Leaves usually distichous, equitant, base sheathing. Inflorescence generally racemose or paniculate or reduced to 1-3 flowers, subtended by 1 or 2 bracts (spathe). Flowers actinomorphic or zygomorphic, bisexual. Perianth biseriate, petaloid, inner and outer tepals (or perigone segments) similar or different, free or united into a basal solid hypanthium, well developed or reduced. Outer segments are known as falls and the inner ones as standard. Stamens 3, opposite the outer tepals. Ovary inferior, mostly 3-locular, placentation axile; style usually trifid, frequently petaloid. Fruit a loculicidal capsule. Seeds globose to ellipsoid or pyriform, variable in shape, sometimes arillate.

A family with 92 genera and c. 1800 species, cosmopolitan in distribution, with greater concentration in South Africa, Eastern Mediterranean and Central and South America. In Pakistan the family is represented by 3 genera and 19 species; whereas 3 genera and 3 species are grown as ornamentals.