Serrated ribbon seagrass

These seagrasses are commonly observed on Pulau Semakau, coexisting with the more dominant Tape seagrass (Enhalus acoroides).

Serrated ribbon seagrass is considered prevalent and widespread throughout the tropical Indo-West Pacific region, typically dominating muddy reef tops. Within reef ecosystems, it grows in conjunction with other seagrass species commonly found in such environments. This seagrass rapidly colonizes Halophila beds as part of natural succession.

Characterized by its long, ribbon-like leaves with blunt, rounded tips, which possess serrations that are sometimes minute, the leaf scars around the erect stem are discontinuous. It features robust rhizomes (underground stems) and has flattened leaf sheaths. Occasionally, the leaves exhibit reddish bands.

It is sometimes confused with other ribbon-like seagrasses. For further guidance on distinguishing between ribbon-like seagrasses, additional resources are available.

This seagrass species has distinct male and female plants, although flowering is rarely observed. The female flowers, identifiable by their prong-like stigma, appear in pairs at the base of the leaves, while the male flowers develop within the leaf sheath. The seeds, measuring approximately 10mm, are dark in color with a hard-coated, beaked nut having three blunt ridges along their length. These seeds are attached to the rhizome.

Dugongs consume this seagrass particularly in areas where smaller seagrass species such as Halophila and Halodule are unavailable.