Thorea Bory, 1808
Lectotype species: Thorea ramosissima Bory
Currently accepted name for the type species: Thorea hispida (Thore) Desvaux
Original publication and holotype designation: Bory de Saint-Vincent, [J.B.G.M.] (1808). Sur un genre nouveau de la Cryptogamie aquatique, nomme Thorea. Annales du Muséum d'Histoire Naturelle 12: 126-135, 1 pl. [pl. 18].
Taxonomic status: currently recognized as a distinct genus.
Most recent taxonomic treatment adopted: Sheath, R.G. (2003). Red Algae. In: Freshwater Algae of North America, Ecology & Classification. (Wehr, J.D. & Sheath, R.G. Eds), pp. 197-224. San Diego: Academic Press.
Description: Branched gametophytic filaments, up to 20-200 cm long, 0.5-3 mm diam. Composed of interwoven, colorless medullary filaments and dense, photosynthetic laterals of limited growth. Olive-green, dark brown to black. Chloroplasts in assimilatory filaments parietal, ribbon-like. Monosporangia solitary or in clusters, formed at base of assimilatory filaments (spore-bearing branch-to-vegetative lateral lenth ratio < 0.3). Sexual reproduction known for a few species. In T. bachmannii spermatangia borne on specialized branches near base of assimilatory filaments, colorless, elliptical or obovoid, 8-10 x 4-7 &m. Carpogonia conical with elongate trichogyne 5-7 &m wide; carpogonial branch short and at base of assimilatory filaments. Carposporophyte sparsely branched and compact. Carposporangia terminal 9-13 x 17-25 µm; carpospores germinate into branched, uniseriate chantransia (= pseudochantransia) stage.
Information contributed by: R.G. Sheath. The most recent alteration to this page was made on 20 Jan 2017 by M.D. Guiry.
Comments: Assimilatory filament ultrastructure typical of florideophytes. Debate as to type of pit plug and its use in ordinal classification. Widespread in tropical to warm temperate, freshwater streams. Typically in alkaline waters (e.g. North America pH 7.5-8.2, specific conductance 180-500 µS cm-1).
Numbers of names and species: There are 23 species names in the database at present, as well as 4 infraspecific names. Of the species names, 16 have 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.
Müller, K.M., Sherwood, A.R., Pueschel, C.M., Gutell, R.R. & Sheath, R.G. (2002). A proposal for a new red algal order, the Thoreales. Journal of Phycology 38: 807-820.
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: 20 January 2017 by M.D. Guiry
Linking to this page: http://www.algaebase.org/search/genus/detail/?genus_id=42778
Please cite this record as:
M.D. Guiry in Guiry, M.D. & Guiry, G.M. 2021. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 22 October 2021.