黑木蕨 陰性水草 African water fern (Bolbitis heudelotii )

Bolbitis heudelotii, named for the botanical explorer of West Africa Jean-Pierre Heudelot (1802–1837),[3] is an aquatic polypody fern growing submerged in rivers and streams, attached to rocks or wood by the threadlike rootlets extending from its rhizomes. It has dark green, pinnate leaves 15–40 cm long and 15–25 cm broad. It grows submerged. The water in its native habitat is fast-moving over sandy or rocky bottoms, very clean, not very hard and slightly acidic. The roots cling to rocks and the sandy beds.