Ceratophyllaceae

Abstract

The Ceratophyllaceae, in the order of Ceratophyllales, is a family of Dicotyledoneae flowering plants, consisting of only one genus, Ceratophyllum Linn., with 6–7 species, cosmopolitan distribution. Plants are perennial submersed herbaceous. Stems are slender and branched. Leaves care cauline, 4–12-whorled, sessile, and exstipulate. Blades are 1–4 times dichotomous, segments linear or filiform, and one laterally dentate. Flowers are unisexual, monoecious, solitary, axillary, and subsessile. Staminate flowers are with 10–20 stamens and short filaments. Pistillate flowers are with 1 pistil and ovary superior, 1-loculed, placentation laminar, and ovule 1 pendulous. Styles are persistent, short or elongate, and stigma decurrent. Fruit is a nut, leathery, ovoid or ellipsoid, apex with long spinous persistent style, basal with two spines, and sometimes two spines above. Seed is 1, unitegmic, endosperm and perisperm absent. Only one species, Ceratophyllum demersum Linn., is illustrated in the chapter.