Cymodocea rotundata

Tsuda, Roy T., U. S., Nadiera Sukhraj & H., J., 2016, Reassessment of Seagrass Species in the Marshall Islands, Micronesica 2016 (4), pp. 1-10 : 4

Remarks: Cymodocea rotundata is clearly distinguished from Thalassia hemprichii by its smooth rhizome, narrow linear leaves and semi-circular seeds (see den Hartog 1970, Phillips & Meñez 1988).

Description: Rhizomes of the Majuro Atoll specimens of C. rotundata were 1.5 mm in diameter with rhizoids descending (up to 9 cm long) opposite the upright leaf-sheath with mainly 3–4 linear, occasionally sickle-shaped, leaves per leaf-sheath. Leaves were 3 mm wide and up to 17 cm long, with 9–12 parallel veins. Approximately 50% of the leaf tips of the herbarium specimens were intact, i.e., not bitten by herbivorous fish or damaged via physical means. The intact leaf tips are mainly rounded, and at times possess slightly notched apices. The fruits are semi-circular in shape, 10 mm long and 5 mm wide, with teeth on the ridges varying in number and length.