Mayaca fluviatilis Aubl.

Etymology Genus Moss-like
Species River; referring to its typical habitat
Family Mayacaceae
Synonyms Biaslia vandellii Roem., Mayaca kunthii Seub., Mayaca michauxii Schott & Endl.
Common Names Stream Bog Moss
Status Exotic: Naturalised
Form Aquatic Herb
Native Distribution Tropical America


I have only seen this freshwater aquatic herb in MacRitchie Reservoir so far. It grows in dense clumps, and the foliage consists of thin blades spiraling around the stem. They emerge at the banks bearing pink flowers with a white centre.

It resembles Hydrilla verticillata but they can be easily differentiate since their leaf arrangement are different. M. fluviatilis leaves are spiral while H. verticillata is whorled with 5 leaves.

Interesting Facts:

Mayaca fluviatilis is sold as an aquarium plant and probably naturalised here because of its release directly into the reservoir or indirectly from its tributaries and spreading to the reservoir subsequently. Even small fragments of the plant are capable of developing into new individuals (Yakandawala & Dissanayake, 2010), making removal difficult.

Macritchie Reservoir being filled the Stream Bog Moss.

At the edge, they emerged from the water bearing flowers.

Closer view of the submerged plant.

Flowers with pink petals and white centre.

The foliage of Mayaca fluviatilis, and close-up showing the spiral arrangement.


Yakandawala K & DMGS Dissanayake. (2010) Mayaca fluviatilis Aubl.: an ornamental aquatic with invasive potential in Sri Lanka. Hydrobiologia, 656: 199-204.

Author: Jake
Posted: 2013-04-27 / Modified: 2019-08-27