Seagrass species of Singapore

Several species of seagrasses grow on our shores. These flowering plants that grow in the sea have fascinating features.

Here's a quick introduction to all the species that can be found in Singapore.

Tape seagrass (Enhalus acoroides) is the longest seagrass found on our shores. The leaf blade is 1-2cm wide and can be 1.5m long!

Pulau Semakau has vast tracts of Tape seagrass meadows that stretch for kilometres! There's also lots of Tape seagrass at Cyrene Reefs.
Male flowers of the Tape seagrass are tiny (see the small white bits?). They form in a bract (the green V-shaped thing) that grows at the base of the plant. The male flowers float and tend to stick to one another. During a bloom of Tape seagrass, little 'rafts' of male flowers are often seen floating on the water. They look like little bits of styrofoam!
The female flower of Tape seagrass is large and emerges on a long coiled stalk. The pale yellowish petals last only for a day or so. Often, all that is seen are the V-shaped bracts. Soon, the large fruit develops. It is a hairy oval capsule that holds several seeds. The seeds are said to be edible and are eaten by some coastal dwellers. The raw seeds are said to taste like chestnuts.

There are several species of Halophila seagrasses. Some have oval leaves and thus called Spoon seagrasses. The various species of oval-shaped Halophila are difficult to differentiate in the field, so all of them are generally referred to as Halophila ovalis complex. These seagrasses are the most commonly encountered on many of our shores.

The beautiful Fern seagrass (Halophila spinulosa) is made up of many little leaflets. Usually a bright green, sometimes with a bluish tint, this seagrass is widespread on Chek Jawa, Pulau Sekudu as well as Changi.

Singapore is home to the delicate Beccarri's seagrass (Halophila beccarrii). The tiny leaves of this seagrass emerges in a rosette of 4-5 leaves. Elsewhere in the world, this seagrass is considered rare. But it is quite commonly seen on Chek Jawa. It is also seen at the Sungei Buloh Wetland Reserve.

There is a large patch of ribbon seagrass (Cymodocea rotundata) on Chek Jawa.
This elegant seagrass is narrower and not as long as Tape seagrass. A related seagrass is Cymodocea serrulata which has a serrated leaf tip and is found on Pulau Semakau and Cyrene Reefs.

Needle seagrass (Halodule sp.) is also often seen on many of our shores.
The leaves may be thin and needle-like, and in some places quite broad and long so that they resemble some other similar seagrasses. Halodule is distinguished by a single prominent central vein in the leaf blade.

Sickle seagrass (Thalassia hemprichii) is indeed sickle-shaped.
A lush meadow of this seagrass grows on Labrador, the last on our mainland.
Sickle seagrass has little flowers with curly 'whiskers'.

Syringodium isoetifolium is a strange seagrass. Its leaf blade is cylindrical, like plastic tubing!
It is commonly seen on Pulau Semakau and Cyrene Reefs.

Learn more about our seagrass meadows in the next article, and how you CAN make a difference for our seagrasses and shores.