''Phycodrys rubens'' is a red marine

alga Algae ( , ; : alga ) are any of a large and diverse group of photosynthetic, eukaryotic organisms. The name is an informal term for a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from u ...

of up to 30 cm long.

Description

''Phycodrys rubens'' is

seaweed Seaweed, or macroalgae, refers to thousands of species of macroscopic, multicellular, marine algae. The term includes some types of ''Rhodophyta'' (red), ''Phaeophyta'' (brown) and ''Chlorophyta'' (green) macroalgae. Seaweed species such as ke ...

which is perennial and can grow to 30 cm long and is strongly red in colour.Bunker, F,.StP.D., Brodie, J.A., Maggs, C.A. and Bunker, .R.2017. ''Seaweeds of Britain and Ireland.'' Second Edition. Wild Nature Press, Plymouth, UK It grows with flat leaf-like blades which are monostromatic, that is composed of a single flat layer of cells and can grow 3 cm wide. These blades can become 3 cm wide and show a clear mid-rib. The blades have a ruffled margin with veins growing out from the central mid-rib with paired lateral veins. The plants grow from a small disk holdfast with an axis to the blades.Maggs, C.A. and Hommersand, M.H. 1993. ''Seaweeds of the British Isles. Volume 1 Rhodophyta Part 3A Ceramiales.'' The Natural History Museum London. Dickinson, C.I. 1963. ''British Seaweeds.'' The Kew Series. Eyre & Spottiswoode The algae are somewhat similar to '' Delesseria sanguinea'' which is also strongly red but has a smooth, not dentate, margin. The shape of the

frond A frond is a large, divided leaf. In both common usage and botanical nomenclature, the leaves of ferns are referred to as fronds and some botanists restrict the term to this group. Other botanists allow the term frond to also apply to the lar ...

is similar to the leaf of an

oak An oak is a tree or shrub in the genus ''Quercus'' (; Latin "oak tree") of the beech family, Fagaceae. There are approximately 500 extant species of oaks. The common name "oak" also appears in the names of species in related genera, notably ''L ...

tree.

Reproduction

The

gametophyte A gametophyte () is one of the two alternation of generations, alternating multicellular organism, multicellular phases in the life cycles of plants and algae. It is a haploid multicellular organism that develops from a haploid spore that has on ...

s are dioecious, that is the male and female phases are on separate plants. The reproductive structures are found at the margins of the blades, the cystocarps as branches attached to the veins and the tetrasporangial sori occur near the apices of the larger bladelets.

Habitat

Commonly found in the

littoral The littoral zone or nearshore is the part of a sea, lake, or river that is close to the shore. In coastal ecology, the littoral zone includes the intertidal zone extending from the high water mark (which is rarely inundated), to coastal areas ...

, sub-littoral in low rock pools and attached to the stipes of large algae such a ''

Laminaria ''Laminaria'' is a genus of brown seaweed in the order Laminariales (kelp), comprising 31 species native to the north Atlantic and northern Pacific Oceans. This economically important genus is characterized by long, leathery laminae and relat ...

''. Found to a depth 30 m.

Distribution

Common on the shores of

Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...

Wales Wales ( cy, Cymru ) is a Countries of the United Kingdom, country that is part of the United Kingdom. It is bordered by England to the Wales–England border, east, the Irish Sea to the north and west, the Celtic Sea to the south west and the ...

, Isle of Man,

Scotland Scotland (, ) is a country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a border with England to the southeast and is otherwise surrounded by the Atlantic Ocean to th ...

including the

Shetland Islands Shetland, also called the Shetland Islands and formerly Zetland, is a subarctic archipelago in Scotland lying between Orkney, the Faroe Islands and Norway. It is the northernmost region of the United Kingdom. The islands lie about to the n ...

and the north-east and south-east of

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe ...

. It is not found in the south-east of England.Hardy, F.G. and Guiry, M.D. 2003. ''A Check-list and Atlas of the Seaweeds of Britain and Ireland'' British Phycological Society The species is found in the North Atlantic from Spitzbergen to Portugal and Canada.

Note

The fronds adhere well to paper and can be dried to make fine specimens.

References

Delesseriaceae {{Rhodophyta-stub