Gracilaria crassa Harvey ex J.Agardh 1876

Division     Rhodophyta
Class     Florideophyceae
Order     Gracilariales
Family    Gracilariaceae

    Thalli yellowish to purple colour, thick, cylindrical form, about 2-4cm tall, 3-4mm in thickness, several shoots arising from discoidal or irregular holdfast. Cortex region one or two layers of cells, outer radially elongated cells 10μm x 8μm and inner cells radially compressed and somewhat larger; hair cells present that produce as tubular hairs, oblong-ovate; transition of cortex to medulla abrupt. Medulla occupy the centre region, central cells large, ovoid to oblong cells, surrounded by broadly oval cells measuring 204-220μm x 234-244μm; outer cells of the medulla smaller, radially compressed progressively smaller towards the periphery, peripheral cells 10-12μm x 22-30μm.Cystocarp dome-shaped, scattered over the thallus. Gonimonemata radiating, with a swollen base and terminal portion with short branches. Tetrasporangia scattered and cruciately divided.


Grows on the surface of the rocks and corals

Distribution in India

Ervadi, Krusudai Islands, Mandapam, Pamban, Rameswaram, Thonithurai