Domain Eukaryota Class Florideophyceae Rank Species | Division Rhodophyta] | |
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Similar Polysiphonia, Fucus spiralis, Ascophyllum nodosum, Rhodomelaceae, Pelvetia canaliculata | ||
Polysiphonia lanosa (Polysiphonia fastigiata (Roth) Greville) is a common species of the red algae (Rhodophyta) often to be found growing on Ascophyllum nodosum.
Contents
Description
The thalli of this species are dense tufts, each thallus up to 7.5 cm generally attached by rhizoids to the fronds of Ascophyllum. The erect cylindrical branches divide pseudodichotomously. A transverse section shows an axial cell surrounded by 12 to 24 perixial cells.
Reproduction
The life history is a sequence of three phases: gametangial, carposporangial and tetrasporangial. Two of the phases are similar. The plants are dioecious with spermatangial branches produced in tufts at the apices of the branches, The Cystocarps are borne, usually singly.with a narrow ostiole from which carpospores are released. The tetraspores occur in spiral seriesresulting from a simultaneous division into 4 equal spores.
Distribution
Common around the British Isles and on the shores of Europe from Iceland, Norway to Spain. Also Greenland and Newfoundland to New England.
