Zannichellia palustris L.   Zannichelliaceae (Horned Pondweed Family)   Native   Horned Pondweed

                                         May Photo

Plant Characteristics:  Perennial slender, branching aquatic herb with creeping rhizome; stems submersed, filiform, sparsely branched, 3-10 dm. long; lvs. opposite, submersed, filiform, entire, flat, 1-nerved, 2-10 cm. long, acute, with sheathing membranous stipules; fls. sessile, unisexual, in bud surrounded by a spathe; staminate fls. consisting of 1 stamen, the filament slender, bearing a 2-celled anther; pistillate fls. consisting of 1 stamen, the filament slender, bearing a 2-celled anther; pistillate fls. 4 (2-6); style short; stigma peltate; fruit an obliquely oblong, flattened, beaked nutlet, pedicelled, 2-4 mm. long, dentate on the back, the flask-shaped beak 0.8-1.5 mm. long; seed orthotropous, the cotyledon coiled.

Habitat:  Common, especially in brackish and subsaline habitats, ponds, streams, and ditches; throughout California; cosmopolitan.  March-Nov. 

Name:  Zannichellia, after G.G. Zannichelli, 1662-1729, Italian botanist.  (Munz, Flora So. Calif. 1013).  Palustris, marsh-loving.  (Bailey 19).

General:  Found only in the creek at 23rd St. but I cannot say it is rare, as I have not investigated other fresh water habitats thoroughly enough to know the frequency of the plant in the study area.  (my comment).       For a species so widespread, Zannichellia palustris is amazingly uniform.  (Mason 89).       About 6 genera, widely distributed, in fresh, brackish or salt water.  (Munz, Flora So. Calif. 1013).

Text Ref:  Hickman, Ed. 1310; Mason 89; Munz, Flora So. Calif. 1013; Roberts 49.

Photo Ref:  April-May 91 # 35.

Identity: by John Johnson.

Computer Ref:  Plant Data 393.

Have plant specimen.

Last edit 7/18/03.