This MedLibrary.org supplementary page on Atractophora hypnoides is provided directly from the open source Wikipedia as a service to our readers. Please see the note below on authorship of this content, as well as the Wikipedia usage guidelines. To search for other content from our encyclopedia supplement, please use the form below:
Related Sponsors
| Audouinella | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Scientific classification | ||||||||||||||
|
Atractophora hypnoides P.L. Crouan & H.M.Crouan is a rare red alga (Rhodophyta) found in the British Isles, France and some Atlantic Islands and is the only species of the genus found in the British Isles. It is attached to the rock or other algae by a small basal disc and is much branched with downgrowing filaments which enclose the main branch or axis forming a cortex. Short filaments of limited growth radiate in whorls from the axis and frequently convert into hairs. The spreading filaments grow irregularly in a diffuse manner. Microscope examination is required for identification.
Contents |
Botanical description
Atractophora hypnoides is the gametangial, that is the sexual reproductive, phase of this alga, tetransporangia are unknown. The gametangial thallus is erect, red and grows to a length of about 10cms. In the life cycle the adult, gametangial phase of the plant, produces spermatangia in clusters and carposporophytes which produce carpospores. On release these germinate and develop into the gametangial phase. No tetrasporangial phase is known. (Dixon and Irvine 1977 p.148)1 However tetraspores released from Rhododiscus pulcherrimus when cultured germinated to form spermitangial and carpogonial branches. The vegetative and reproductive development corresponded closely with that described for Atractophora hypnoides.2 There are many other similar finely branched algae: Audouinella, Antithamnion, Dasya, Spyridia and others.
Distribution
It is mainly a western species in the British Isles with records from the Inner Hebrides of Scotland, Galway and County Cork in the south of Ireland, a few records from Wales and south-western England. There are only four records from Northern Ireland: County Antrim from Rathlin Island and Loughan Bay and in County Down at Greenore Point and near the entrance of Strangford Lough and five from the Republic of Ireland. It is recorded from several sites in England (counties: Cornwall, Devon and Dorset) and Wales but most often in the western islands of Scotland. 3 It is also recorded from the Channel Islands and the Isle of Man. In Europe it is known from the coasts of France.
Life Cycle
The vegetative and reproductive development of Rhododiscus pulcherrimus corresponds closely to that described for Atractophora hypnoides. 2
Habitat
The species grows epiphytically on coralline algae and is to be found only in the sublittoral to 20m depth. 1
References
- ^ a b Dixon, P.S. and Irvine, L.M. 1977. Seaweeds of the British Isles. Volume 1. Rhodophyta. Part 1. Introduction, Nemalionales, Gigartinales. British Museum (Natural History), London. ISBN 0 565 00781 5
- ^ a b Maggs, C.A., Guiry, M.D. and Irvine, L.M. 1983. The life history of an isolate of Rhodiscus pulcerimus (Naccariaceae; Rhodophyta) from Ireland.Abstract of papers read at the winter meeting at the University of Newcastle upon Tyne. Br. phycol. J. 18: 206
- ^ Hardy, F.G. and Guiry, M.D. 2006. A Checklist and Atlas of the Seaweeds of Britain and Ireland. British Phycological Society, London. ISBN 3-906166-35-X
External links
Wikipedia content modification information:
- This page was last modified on 24 March 2008, at 12:59.
Wikipedia Authorship and Review
Wikipedia content provided here is not reviewed directly by MedLibrary.org. Wikipedia content is authored by an open community of volunteers and is not produced by or in any way affiliated with MedLibrary.org.
Wikipedia Usage Guidelines
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article on "Atractophora hypnoides".
The URL for this specific entry is:
All Wikipedia text is available under the terms of the GNU Free Documentation License. (See Copyrights for details). Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc.