159,861 species and infraspecific names are in the database, 22,561 images, 61,894 bibliographic items, 468,273 distributional records.

Hydrurus C.Agardh, 1824, nom. cons.

Empire Eukaryota
Kingdom Chromista
Phylum Ochrophyta
Class Chrysophyceae
Order Hydrurales
Family Hydruraceae

Holotype species: Hydrurus vaucheri C.Agardh

Currently accepted name for the type species: Hydrurus foetidus (Villars) Trevisan

Original publication and holotype designation: Agardh, C.A. (1824). Systema algarum. pp. [i]-xxxvii, [1]-312. Lundae [Lund]: Literis Berlingianis [Berling].
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Taxonomic status: currently recognized as a distinct genus.

Most recent taxonomic treatment adopted: Kristiansen, J. & Preisig, H.R. (2001). Encyclopedia of Chrysophyte genera. Bibliotheca Phycologica 110: 1-260.

Description: Cells arranged peripherally in large (up to 30 cm or more) bushy mucilaginous thalli, fixed to stones. Growth apical. Vegetative cells oval, with a 2-lobed chloroplast, with a pyrenoid, several dictyosomes, and contractile vacuoles. At swarmer formation, most of the thallus is dissolved into swarmers; each cell divides into two swarmers. Swarmers are tetrahedral, their shape maintained by a skeletal system of microtubules. There is one visible flagellum; the other is only seen in EM, reduced to a short stump hardly longer than its basal body. The flagellar roots constitute a complex system, most notable is a rhizoplast in connection with the nucleus and a large band-shaped microtubular root, from which the skeletal microtubules extend. Chloroplast has a large immersed pyrenoid, but no stigma, and is provided with a longitudinal furrow in which a mitochondrion is located. There are several contractile vacuoles and also several dictyosomes. Nuclear envelope intact during mitosis. Reproduction by zoospores which have a remarkable similarity to those of Celloniella in shape and flagellar apparatus. Stomatocysts lenticular, with an equatorial wing, as in Phaeodermatium. It might be possible that Phaeodermatium is part of the Hydrurus life history. Hydrurus is common in cold clear mountain streams worldwide. It has a peculiar and unpleasant smell described as foetid. During warm weather, the macroscopic form degrades and cysts form.

Information contributed by: J. Kristiansen. The most recent alteration to this page was made on 20 Oct 2015 by M.D. Guiry.

Numbers of names and species: There are 5 species names in the database at present, as well as 8 infraspecific names. Of the species names, 2 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.

Nicholls, K.H. & Wujek, D.E. (2003). Chrysophycean Algae. In: Freshwater Algae of North America. (Wehr, J.D. & Sheath, R.G. Eds), pp. 471-510. San Diego: Academic Press.

Klaveness, D., Brate, J., Patil, V., Shalchian-Tabrizi, K., Kluge, R., Gislerod, H.R. & Jakobsen, K.S. (2011). The 18S and 28S rDNA identity and phylogeny of the common lotic chrysophyte Hydrurus foetidus. European Journal of Phycology 46(3): 282-291.

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: 23 April 2002 by M.D. Guiry

Verified by: 20 October 2015 by M.D. Guiry

Linking to this page: http://www.algaebase.org/search/genus/detail/?genus_id=44157

Citing AlgaeBase
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 15 January 2021.

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