Inflorescence and flower development in Costus scaber (Costaceae)

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
Bruce K. Kirchoff, Emeritus Professor (Creator)
The University of North Carolina at Greensboro (UNCG )
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Abstract: The inflorescence of Costus scaber terminates an erect axis of a sympodial rhizome system. Primary bracts are borne on the inflorescence in spiral monostichous phyllotaxy. One-flowered cincinni occur in the axils of these bracts. Each cincinnus consists of an axis bearing a terminal flower and a secondary bract on the anodic side of the flower. A tertiary bud forms in the axil of this bract but does not complete development. The inflorescence terminates by cessation of growth of the apex and precocious development of the primary bracts. Floral organs are formed sequentially beginning with the calyx, and continuing with the corolla and inner androecial whorl, outer androecial whorl, and gynoecium. All flower parts, except for the calyx, originate from a ring primordium. Regions of this primordium separate to form the corolla and inner androecial members. It was not possible to determine the sequence of androecial member formation. The labellum is composed of five androecial members, three from the outer whorl and two from the inner. The third member of the inner whorl forms the stamen and its petaloid appendage. The gynoecium forms from three conduplicate primordia. The margins of two of these primordia are the product of phyletic fusion.

Additional Information

Canadian Journal of Botany 62: 339-345
Language: English
Date: 1988
Inflorescence, Costus scaber

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