Seagrasses belong to the realm of plants, division seed plants, class angiosperms also called flowering plants. The angiosperms are the plant group with the most species, with 226,000 known species.
Very few of them live underwater. Around 16 species are known.
Most of these live in cool waters. The seagrass has roots, leaves, and flowers. Reproduction is sexual by seed formation.
Seagrass meadows are an important component in the marine ecosystem. They literally function as the nursery of marine life. In addition, many animal species, such as fish, snails, turtles and manatees, feed on them.
In warm waters, such as the Red Sea, only a few seagrass species are encountered. The most common are the following 3 species.
Sawed seagrass (Cymodocea serruluta)
Widely distributed in shallow lagoons. The broad leaves, 4-9 mm, are curved, herbaceous with short blades..
Fan seagrass (Thalassodendron ciliatum)
Found in semi-protected zones and at the base of reefs..
The broad curved leaves, up to 1.4 cm wide, are up to 15 cm long..
Binding seagrass (Halodule universis)also known asdugong seagrass.
Inhabits bays protected in shallow 0.5 -6 m depths.
Slim phylloids, 5 mm, growing shallowly directly on the rootstock..
Photos by Johann Vifian.
Sources: Red Sea Coral Reef Guide Ewald Lieske / Robert Meyers