Enhalus acoroides 

Enhalus acoroides in situ Enhalus acoroides whole plant Found from lower eulittoral zone into the subtidal, on sand and gravel sediments. Long blade like leaves (30–150 cm in length by 1–2 cm wide). Rhizome coarse with many stout unbranched roots; short internodes. This one of the largest seagrasses in the region.

Thalassia hemprichii

Thalassia hemprichii in situ Thalassia hemprichii plant Found from mid eulittoral zone to shallow subtidal, on muddy sand. Curved leaves (5-40 cm long by 4–11 cm wide) with mass of old leave sheaths at base. Rhizome with distinctive internodes and brown scales. 4 or more internodes between shoots.

Cymodocea rotundata 

Cymodocea rotundata in situ Cymodocea rotundata plant Found on lower eulittoral sandy – muddy sediments. Leaves straight with rounded smooth tips (6–15 cm long by 2–4 cm wide) with shaggy mass of old sheaths at base. Rhizome slender with internodes 1 to 4 cm apart.

Cymodocea serrulata

Cymodocea serrulata plant Found from eulittoral zone, on sandy sediments. Leaves similar to C. rotundata but tips are serrated. Base of leaves with distinct light-coloured conical region. Rhizome stout with internodes 2–5 cm apart.

Syringodium isoetifolium

Syringodium isoetifolium in situ Syringodium isoetifolium plant Found from edge of eulittoral zone into the subtidal, on sandy – muddy sediments. Leaves narrow and rounded up to 20 cm long and 1–3 cm wide. Rhizome thin with internodes at 1–3 cm intervals.

Halodule uninervis

Halodule uninervis in situ Halodule uninervis Found from eulittoral zone on muddy sand sediments. Leaves narrow (15 cm in length by 1–3 cm wide) with distinct midrib, leaf tip tridentate. Rhizome creeping with internodes at intervals of 1 to 5 cm.

Halophila ovalis

Halophila ovalis in situ Halophila ovalis plant Found from eulittoral to edge of sublittoral zones, on muddy sand (often difficult to see) Leaves oval, small (up to 4 cm in length), oval, in pairs on thin petioles (stalks); distinctive midrib with 8 to 20 pairs of cross veins. Rhizome thin with 0.5 to 5 cm between internodes which are covered by two transparent scales.

Halophila minor

Halophila minor Found from lower eulittoral down to shallow subtidal zone on muddy sand. Leaves small elongated oval (0.6–1.2 cm in length by 3–6 cm wide). 7–12 pairs of cross viens. Rhizome similes to H. ovalis


Den Hartog, C. 1970. Seagrasses of the world. North Holland Publishing, Amsterdam. 275pp.

Philips, R.C. & Meñez, E.G. 1988. Seagrasses. Smithsonian Contributions to Marine Science, 34: 104pp.

Philips, R.C & McRoy, C.P. (Eds) 1990. Seagrass research methods. UNESCO Monographs in oceanographic
methodology 9: 210pp.

Short, F. T., Coles, R.G., Short, C.A. 2001. Global seagrass research methods. Elsevier, Amsterdam. 473pp.

Return to previous menu

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith