Typhaceae

Abstract

Glabrous, perennial, herbaceous amphiphytes from scaly, sympodial, starchy rhizomes, emergent from shallow water or growing on wet soil, sometimes wholly submerse and floating. Leaves alternate, distichous, with strongly sheathing base and an elongate, parallel-veined blade, basal in sterile plants and forming an erect false stem, on flowering plants also dispersed along the stem, rarely stem bearing only hypsophylls. Inflorescence racemose, the numerous monoecious, hypogynous flowers grouped into dense, complex globular heads or very dense cylindric spikes; perianth of 1-several inconspicuous tepals or more or less numerous slender bristles; stamens (1-)3(-8), the filaments distinct or connate; anthers basifixed, tetrasporangiate, dithecal; gynoecium pseudomonomerous, with a single fertile carpel, less often with 2–3 ± fully developed carpels connate to form a compound ovary, the stigmas or branches of the common style accordingly 1–3; ovule solitary (in each locule), pendulous from near the top of locule, apotropous, anatropous, bitegmic, crassinucellar. Fruit small, dry, indehiscent or dorsally dehiscent; seed with a straight embryo that has a single terminal cotyledon and a lateral plumule; embryo surrounded by copious, mealy endosperm and thin perisperm, the endosperm containing starch, protein, and oil. x = 15.