Indian toothcup

Description

Rotala indica is a species of plant that is native to warmer regions of Asia, where it often grows as an annual weed in rice paddies. It has been introduced to other regions where rice is cultivated, such as Northern Italy. The leaves of Rotala indica are 0.5-1.7 cm long and obovate to spatulate with an obtuse tip. A distinctive feature of this species is its "cartilaginous" leaf margin, which appears thicker and whiteish-transparent under magnification or microscopy. In the submersed form, Rotala indica has a strictly upright growth habit, dense foliage, and a relatively thick stem that does not ramify much. Under sufficient light, the shoot tip becomes reddish. The emersed form of the plant grows low to the ground with small reddish flowers appearing on short lateral shoots or in leaf axils along the stem. Rotala indica is a slow-growing species that requires high light intensity and nutrient supply in the aquarium. It is best planted as individual groups of stems of different lengths in the middle ground of a tank.