Domain Eukaryota Class Florideophyceae Family Rhodomelaceae | Division Rhodophyta Order Ceramiales Genus Polysiphonia | |
Similar Polysiphonia, Ceramiales, Polysiphonia fucoides, Polysiphonia morrowii, Rhodomelaceae | ||
Polysiphonia atlantica is a small filamentous species of red marine algae Rhodophyta. The thalli form small tufts up to 3 cm long. The axes are ecorticate consisting of axial cells surrounded by four periaxial cells.
Contents
Description
Polysiphonia atlantica is about 3 cm high and dark reddish-brown in colour. This small marine algae grows in tufts from prostrate cells. It produces numerous branches all growing to the same length. It consist of a series of axial cells surrounded by 4 periaxial cells which are elongate to the same length as the axial cells which are ecorticate. Attached by rhizoids produced by the periaxial cells.
Reproduction
The life history is a sequence of three phases: gametangial, carposporangial and tetrasporangial. The plants are dioecious with spermatangial branchlets at the apices of the branches, cystocarps are slightly urceolate. The tetrasporangia occur the branches in a straight series.
Habitat
Growing on rock, mussels other invertebrates or epiphytic. Between high and low water levels.
Distribution
Records have been made from the British Isles- England, Ireland, Wales and Scotland, to Morocco, east coast of America and the Indian Ocean. Most of the records from the British Isles are probably those of Polysiphonia stricta.