Podostemaceae

Submerged aquatic perennials with branched, green, creeping roots anchored by fleshy disks to rocks in rapidly flowing water. Stems branched. Leaves stalked, alternate, the base boat-shaped and forming a sheath around the stem, usually forked into many thread-lke segments that are rigid and resemble algae. Plants become reproductive when water levels drop exposing plants to air.

Flowers tiny, 1-12 per stem, solitary in leaf axils on stalks that become longer in fruit; each developing flower completely surrounded by a club-shaped sac (spathella) that ruptures by the time the flower is fully developed. Each flower produces both pollen and seeds, and is bilaterally symmetric. Stamens usually 2, restricted to 1 side of the flower, arising from a common stalk that is longer that the stalk of either stamen. Carpels 2, fused to form 1 pistil that is on a short stalk; ovary located above point of attachment of other flower parts (superior), at flowering ovary (and subsequently the capsule) is oriented at an angle to the stalk; stigmas 2. Sepals and petals replaced by 3 tiny, linear, scale-like structures (tepals), one on either side of the ovary, the third between the stalks of the stamens. Fruit a ribbed capsule with 2 chambers and many tiny seeds that become sticky when wet.