''Polysiphonia elongella'' Harvey in W.J. Hooker Hardy, F.G. and Guiry, M.D. 2003 A Checklist and Atlas of the Seaweeds of Britain and Ireland. The British Phycological Society. is a branched species of marine

red algae Red algae, or Rhodophyta (, ; ), make up one of the oldest groups of eukaryotic algae. The Rhodophyta comprises one of the largest Phylum, phyla of algae, containing over 7,000 recognized species within over 900 Genus, genera amidst ongoing taxon ...

in the genus in the ''

Polysiphonia ''Polysiphonia'', known as red hair algae, is a genus of filamentous red algae with about 19 species on the coasts of the British Isles and about 200 species worldwide, including Crete in Greece, Antarctica and Greenland. Its members are known by ...

'' in the

Rhodophyta Red algae, or Rhodophyta (, ; ), make up one of the oldest groups of eukaryotic algae. The Rhodophyta comprises one of the largest phyla of algae, containing over 7,000 recognized species within over 900 genera amidst ongoing taxonomic revisions. ...

Description

This marine alga grows as small cylindrical thalli branching to about 10 cm long. It grows as an erect axis attached by a disk-like holdfast. The main axis is unbranched towards the base but bears lateral branches higher up. Each erect axes is composed of a polysiphonous axis with a central row of cells surrounded 4 perixial cells all of the same length.Maggs, C.A. and Hommersand, M.H. 1993. ''Seaweeds of the British Isles Volume 1 Rhodophyta Part 3A Ceramiales'' The Natural History Museum London The branches, unlike ''Polysiphonia elongate'', are only slightly constricted at their base. Cortication filaments grow downwards in the grooves between the periaxial cells and lower down these form a complete cortication. Trichoblasts are borne near the apices.

Reproduction

Globose cystocarps and bisporangia are recorded, the tetrasporangia are sparse.

Habitat

Grows below low-water on sheltered shores.

Distribution

The species is recorded from

Ireland Ireland (, ; ; Ulster Scots dialect, Ulster-Scots: ) is an island in the North Atlantic Ocean, in Northwestern Europe. Geopolitically, the island is divided between the Republic of Ireland (officially Names of the Irish state, named Irelan ...

Great Britain Great Britain is an island in the North Atlantic Ocean off the north-west coast of continental Europe, consisting of the countries England, Scotland, and Wales. With an area of , it is the largest of the British Isles, the List of European ...

, including the

Isle of Man The Isle of Man ( , also ), or Mann ( ), is a self-governing British Crown Dependency in the Irish Sea, between Great Britain and Ireland. As head of state, Charles III holds the title Lord of Mann and is represented by a Lieutenant Govern ...

, the

Shetland Islands Shetland (until 1975 spelled Zetland), also called the Shetland Islands, is an archipelago in Scotland Scotland is a Countries of the United Kingdom, country that is part of the United Kingdom. It contains nearly one-third of the Uni ...

and the

Channel Islands The Channel Islands are an archipelago in the English Channel, off the French coast of Normandy. They are divided into two Crown Dependencies: the Jersey, Bailiwick of Jersey, which is the largest of the islands; and the Bailiwick of Guernsey, ...

. The few records from

Northern Ireland Northern Ireland ( ; ) is a Countries of the United Kingdom, part of the United Kingdom in the north-east of the island of Ireland. It has been #Descriptions, variously described as a country, province or region. Northern Ireland shares Repub ...

are old and require confirmation.Morton, O. 1994. ''Marine Algae of Northern Ireland''. Ulster Museum Also recorded from

France France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...

and the

Mediterranean The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern ...

References

{{Taxonbar, from=Q30594992 Rhodomelaceae