Costaceae

By: Atsuko Takano & Srijana Shah

Taxon Description 

Perennial rhizomatous herbs. Rhizome tuberous and fleshy. Pseudostems formed by overlapping leaf sheaths. Stems erect, herbaceous, unbranched or sparsely branched. Leaves petiolate, simple, entire, spirally arranged, sheathing leaf bases forming closed or partially open tubes, presence of mucilage, ligule present, lamina narrowly to broadly elliptic. Inflorescences terminal or occasionally on separate, cone-like spike; bracts often brightly colored, imbricate bracteoles present. Flowers bisexual, zygomorphic, showy, fragrant. Calyx 3-lobed, tubular. Corolla 3-lobed, delicate, tubular, lobes equal to unequal. Staminodes 5, fusion of staminodes forming large, petaloid labellum. Single fertile stamen, filament broad; anther often basifixed. Carpels 3, syncarpous. Ovary inferior, trilocular with axile placentation; style 1, slender, passing through the stamen; stigma funnel-shaped or capitate. Fruit a capsule, fleshy to dry. Seeds numerous, arillate.

Taxon Statistics

Worldwide 8 genera and 163 species. One genus (Hellenia) and two species in Nepal.