Coeloseira compressa Hollenb

Order Family    Genus Rhodymeniales Lomentariaceae Coeloseira

Coeloseira compressa Hollenb

Characteristics

The alga forms a pach of about 6 -8 cm on the rocky substratum; plant is saxicolous, tubular, septate, irregularly branched; branches are stoloniferous with a peg like holdfast; thallus is ceaspitose, irregularly branched, mostly 2-3 cm long and light red in colour; branches 1-2 mm wide prominently constricted at the septa and mostly compressed thallus which becomes oval during reproduction; apical cells with dens cytoplasm are present at the apex of tubular branches; tubular branch is hollow 1 cell thick and continuous while it is solid and pseudoparenchymatous in the rhizoidal and nodal region. the peripheral layer of the hollow internodal portion consists of thick (50 - 60µ) primary cells with dense chromatophores medullary filaments are developed from the primary cells by periclinal division; primary cells undergo periclinal division resulting into the outer cell which form the peropheral cells and the inner cells which gives rise to either medullary filaments or gland cells; polysporangia are scattered mostly in subterminal segments of branches and are 100 to 160µ diameter with 8-12 spores in each polysporangia; polysporangia are developed from the peipheral primary cells by an oblique division when maure the sporangia bulge into the central cavity ; peripheral cells do no completely cover mature sporangia.