Polysiphonia fibrata
# Polysiphonia fibrata

Polysiphonia fibrata is a species of Polysiphonia that grows as small dense tufted and finely branched marine alga in the Rhodophyta.

## Description

The branches of P. fibrate are numerous and much interwoven forming tufts up to 20 cm long. They are fine, terete, cylindrical, erect and dull brownish-red in colour. The branches consist of a central axis with 4 pericentral cells all of the same length as the axial cells. The branches become corticated near the base. Rhizoids and trichoblasts are abundant.

## Reproduction

The plants are dioecious. Spermatangia are borne near the tips of the branches. The cystocarps are clearly shortly stalked. Tetrasporangia are formed in the branches near the tips.

## Habitat

To be found on rock, limpets, mussels and on other algae in rock pools at mid-tide and low water.

## Distribution

Common around Britain including Shetland and Ireland. Also recorded from Spain, and France.

## Note

Other species are similar to P. fibrata and difficult to distinguish.

