Plants annual or perennial; monoecious, pistillate and staminate spikelets on separate rames in the same inflorescence. Culms to 3 m, erect, creeping, or floating, branched; internodes solid. Leaves not aromatic; ligules membranous. Inflorescences axillary, of 2(3) rames, 1 pistillate, the other(s) staminate, pistillate rames completely enclosed in indurate, globose to cylindric, modified leaf sheaths, termed involucres, from which the staminate rames protrude. Pistillate rames each with 3 spikelets, 1 sessile and pistillate, the other 2 pedicellate and rudimentary; sessile spikelets somewhat dorsally compressed; glumes coriaceous, beaked; stigmas protruding from the involucres. Caryopses more or less globose. Staminate rames flexible, exserted from the involucre; spikelets in pairs or triplets, 1 sessile, the other(s) pedicellate, reduced, or absent; lower glumeschartaceous, with 15 or more veins, 2-keeled, keels winged above; upper glumes similar, with 1 keel; lower florets sometimes sterile; upper florets staminate; stamens 0 or 3; lodicules 2. Pedicels not fused to the rame axes. x = 5. Name from the Greek koix, a palm.

Coix is a genus of about five species, one of which has been introduced into the Flora region. All the species are native to tropical Asia, where C. lacryma-jobi and, to a lesser extent, C. gigantea are harvested for food.

1.   Coix lacryma-jobi L.
Job's-Tears

Plants annual or perennial. Culms to 3 m. Leaves mostly cauline, evidently distichous; blades to 75 cm long, 1.5-6 cm wide. Involucres usually 8-12 mm, varying in color. Lower glumes of functional pistillate spikelets 6-10 mm, hyaline below, 5-7-veined, with a 1-3 mm coriaceous beak. Staminate rames 10-35 mm, with 3-25 spikelet pairs, disarticulating at maturity; spikelets 5-9 mm, dorsally compressed; glumes exceeding the florets, with 15+ veins; lower glumes elliptic to obovate, somewhat asymmetrical, margins folded inward, apices obtuse; upper glumes lanceolate to narrowly elliptic, keels often winged, apices acute; upper lemmas 5-8 mm, hyaline, elliptic to ovate, 3-veined; upper paleas similar but 2-veined; anthers 3-6 mm. 2n = 20.

Coix lacryma-jobi is a tall, maize-like plant. In North America, it is usually grown as an ornamental, but it has become established at scattered locations in the Flora region. The involucres, which can be used as beads, may be white, blue, pink, straw, gray, brown, or black, with the color being distributed evenly, irregularly, or in stripes. Cultivars with easily removed involucres are grown for food and beverage, especially in Asia.