BOTANY WITH BASICS OF HYDROBOTANY (AQUATIC PLANTS OF UKRAINE) - B.Ye. Yakubenko - 2011

X. SEED PLANTS

Family Zannichelliaceae (Horned Pondweed Family).

Marsh and aquatic plants with creeping rhizomes. Leaves linear, with large stipules, submerged in Water. Rarely, leaves are sheathing with two auricles. Flowers unisexual, plants monoecious, staminate and pistillate flowers closely grouped, positioned singly or in pairs in the leaf axils. Perianth absent, stamens one, rarely two on short filaments, anthers two-celled, attached to the connective. Flowers surrounded by a transparent, deciduous envelope. Ovary consists of two to five carpels, style long, stigma peltate or funnel-shaped. Fruits oblong, slightly compressed.

Includes three genera and 15 species distributed in fresh and brackish water bodies of both hemispheres. In Ukraine, there is one genus and three species.

Horned pondweed (Zannichellia palustris L.). An aquatic plant with creeping, slender, thread-like stems 8-40 cm long, branched, with adventitious roots at the nodes. Leaves 1.5-4.5 cm long, narrow, thread-like, light green. Staminate inflorescence on a long stalk, pistil with a short style, accounting for half the length of the fruitlet. Fruitlets oblong, narrow, up to 2 mm long and 0.75 mm wide, sessile or on short stalks. Flowers in June-August. Exhibits polymorphism.

Grows in eutrophic slightly saline or fresh water bodies, estuaries, and floodplain lakes throughout Ukraine; common in the Steppe, sporadic in the Forest-Steppe, and rare in Polissya and the Pre-Carpathians.

Along the shores of marine lagoons, brackish lakes and water bodies, in marine estuaries of the Steppe and in Crimea grow pedunculate zannichellia (Z. pedunculata Reichenb.) and large zannichellia (Z. major Boenn. ex Reichenb.).

Technical, forage, ornamental, and shore-protecting plants. The leaves contain fats (2.6%), protein (27.8 mg/kg), fiber, micro- and macroelements. Large zannichellia is a promising plant for Introduction into cultivation.