Ceratophyllaceae

Aquatic, under water, non-woody (herbaceous), rootless, free-drifting perennials with long branching stems forming long tangled masses.

Leaves whorled, on short stalks or unstalked, stiff or flaccid, deeply dissected, repeatedly forking into narrow linear to thread-like segments that may or may not be toothed along edges.

Flowers small, inconspicuous, 1-several per node, supported by bracts in leaf axils; each flower producing either pollen or seeds, in separate flowers on the same plant. Pollen-producing flowers are usually above seed producing flowers; rely on water to carry pollen to the flowers that will produce seed. Sepals and petals none. Bracts linear, tiny, 8-15 in a single whorl, fused at base.  Stamens mostly 10-20 per pollen-producing flower, with short broad stalks, separate from one another, spirally arranged on the flattened end of the flower stalk. Carpels (and pistil) 1 per each of the seed-producing flowers, with a narrow thread-like style; ovary located above the point of attachment of the bracts (superior). Fruit achenes, with 2 or more spines, a very thin seed coat and one seed.