155,122 species and infraspecific names are in the database, 21,785 images, 59,952 bibliographic items, 434,112 distributional records.

Postelsia Ruprecht, 1852

Empire Eukaryota
Kingdom Chromista
Phylum Ochrophyta
Class Phaeophyceae
Subclass Fucophycidae
Order Laminariales
Family Laminariaceae

Holotype species: Postelsia palmaeformis Ruprecht

Original publication and holotype designation: Ruprecht, F.J. (1852). Neue oder unvöllstandig bekannte Pflanzen aus dem nördlichen Theile des Stillen Oceans. Mémoires de l'Académie Impériale des Sciences de Saint-Pétersbourg, Sixième Série, Sciences Naturelles 7: 55-82, 8 pls.
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Taxonomic status: currently recognized as a distinct genus.

Most recent taxonomic treatment adopted: Silberfeld, T., Rousseau, F. & Reviers, B. de (2014). An updated classification of brown algae (Ochrophyta, Phaeophyceae). Cryptogamie Algologie 35(2): 117-156.

Taxonomic notes
Arthrothamnaceae (Jackson et al., 2017). - (2 May 2017) - Wendy Guiry

Description: Thallus to 60 cm tall, erect, annual, with a palm tree-like aspect. Holdfast compact, composed of stout, branched haptera. Stipe thick, tubular, thicker at base than at apex; both erect and resilient. Numerous blades borne singly on simple branches arranged radially at top of stipe. Blades narrow, tapering to a point distally, with dentate margins, both surfaces with deep, parallel grooves along the entire length, the grooves of one surface alternating with those of the other. Spores produced in unilocular sporangia with paraphyses, in sori covering most of blade. Gametophytes dimorphic, dioecious, oogamous, branched uniseriate filaments; growing to a small size and producing gametes, even in the absence of blue light or added iron in the medium, two conditions found to be necessary for gametogenesis in gametophytes of other members of the Laminariales.

Information contributed by: R.J. Lewis & M.D. Guiry. The most recent alteration to this page was made on 26 Jul 2016 by M.D. Guiry.

Comments: Postelsia palmaeformis occurs in dense "groves" on intertidal shores exposed to extreme wave force on the Pacific coast of North America. The dense patches may be the result of limited dispersal of spores, which mainly occurs within 3 m of an existing patch. This dispersal apparently occurs from emerged plants as the spores are released and flow along the grooves in the blades, dripping onto the substratum below. Sporophytic thalli may grow on existing algae or barnacles, resulting in these competitors being overgrown or ripped out, leaving bare rock, which is the most suitable substratum for successful growth and persistence. Small populations often do not persist from year to year while large populations generally do.

Numbers of names and species: There is only one species or infraspecific name in the database at present, which has been flagged as accepted taxonomically on the basis of the listed literature under the species name. In some instances, opinions on taxonomic validity differ from author to author and users are encouraged to form their own opinion. AlgaeBase is a work in progress and should not be regarded as a definitive source only as a guide to the literature..

Names: ('C' indicates a name that is accepted taxonomically; 'S' a homotypic or heterotypic synonym; 'U' indicates a name of uncertain taxonomic status, but which has been subjected to some verification nomenclaturally; 'P' indicates a preliminary AlgaeBase entry that has not been subjected to any kind of verification. For more information on a species click on it to activate a link to the Species database):

Click here to also show infraspecific names in the list below.

Jackson, C., Salomaki, E.D., Lane, C.E. & Saunders, G.W. (2017). Kelp transcriptomes provide robust support for interfamilial relationships and revision of the little jnown Arthrothamnaceae (Laminariales) (Letter). Journal of Phycology 53(1): 1-6.

Verification of data
Users are responsible for verifying the accuracy of information before use, as noted on the website Content page.

Some of the descriptions included in AlgaeBase were originally from the unpublished Encyclopedia of Algal Genera, organised in the 1990s by Dr Bruce Parker on behalf of the Phycological Society of America (PSA) and intended to be published in CD format. These AlgaeBase descriptions are now being continually updated, and each current contributor is identified above. The PSA and AlgaeBase warmly acknowledge the generosity of all past and present contributors and particularly the work of Dr Parker.

Descriptions of chrysophyte genera were subsequently published in J. Kristiansen & H.R. Preisig (eds.). 2001. Encyclopedia of Chrysophyte Genera. Bibliotheca Phycologica 110: 1-260.

Created: 28 December 2000 by M.D. Guiry

Verified by: 21 June 2014 by M.D. Guiry

Linking to this page: http://www.algaebase.org/search/genus/detail/?genus_id=42120

Citing AlgaeBase
Please cite this record as:
M.D. Guiry in Guiry, M.D. & Guiry, G.M. 2019. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 23 April 2019.

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