Dictyota dichotoma (Hudson) Lamouroux. Harvey 1847

Division     Ochrophyta
Class     Phaeophyceae
Order     Dictyotales
Family    Dictyotaceae
Basionym     Ulva dichotoma Hudson

    Thalli ribbon like, light brown darker near the base, 5–10 cm long attached by means of cuneate disc, 6-10 mm wide. Tlalli regularly dichotomously branched at intervals of 0.9–3 cm, branches 2.5 –6.5 mm broad. Thalli almost linear and tapering gradually from lower to upper parts of the thallus, rarely spirally twisted axes. Apex more or less rounded to apiculate apices, 1.5–3.2 mm broad. Thallus composed of a cortical layer of thin walled rectangular cells with many discoidal chromatophores, 15-19 length and 9-13 µm breadth, a medulla of large rectangular, thick walled cells, 63-80 µm length and 21-53 µm breadth.

    Reproduction: Tetrasporangia densely scattered on the surface of the thallus except near the margins, usually single or in groups of 2-4, sometime associated with tuft of hairs, 60–83 µm in diameter.

Distribution in India

Okha, Shivrajpur, Veraval (Gujarat), Rameswaram, Tuticorin (Tamil Nadu), (Krishnamurthy and Joshi, 1969), Andaman Islands.