Klebsormidium P.C., Mattox & W.H.Blackwell, 1972
Holotype species: Klebsormidium flaccidum (Kützing) P.C.Silva, K.R.Mattox & W.H.Blackwell
Original publication and holotype designation: Silva, P.C., Mattox, K.R. & Blackwell, W.H., Jr (1972). The generic name Hormidium as applied to green algae. Taxon 21: 639-645.
Taxonomic status: currently recognized as a distinct genus.
Most recent taxonomic treatment adopted: Silva, P.C., Mattox, K.R. & Blackwell, W.H., Jr (1972). The generic name Hormidium as applied to green algae. Taxon 21: 639-645.
Description: Filaments uniseriate and unbranched, without polar differentiation. Free-floating or attached via hyaline, gelatinous, spherical-like holdfast surrounding basal cell. Cells basically cylindrical. Cell wall thin and smooth, under adverse conditions sometimes markedly thickened, lamellate, and verrucose, simultaneously with H-pieces wrapping transverse cell walls. Chloroplast single and parietal, laminate or girdle-shaped, often withdrawn and then elliptical or discoid, incompletely encircling cell lumen and not lobed, usually occupying not more than one half of cell periphery. Pyrenoid single, embedded in center of chloroplast, usually surrounded by distinct starch envelope. Asexual reproduction by biflagellate zoospores or by walled aplanospores, sometimes following dormancy.
Zoospores dorsiventral with flagella subapically and asymmetrically inserted; stigma absent. Zoospores formed singly in unspecialized cells, escaping through distinct lateral pore in cell wall, producing no holdfast on germination. Vegetative multiplication by fragmentation into unicells ("Vermehrungsakineten"), or few-celled fragments. Akinetes infrequent, elliptical , surrounded by thick membrane enclosing cell contents rich in assimilates. Sexual reproduction purportedly by anisogamous fusion of biflagellate spindle-shaped gametes with distinct stigmas.
Information contributed by: G.M. Lokhorst & M.D. Guiry. The most recent alteration to this page was made on 4 Jan 2015 by Paul Gabrielson.
Comments: Klebsormidium was proposed in 1972 to resolve confusion in application and status of Hormidium. Earlier proposals to replace Hormidium by, e.g. Hormococcus Chodat, Pseudoulothrix Pascher and Chlorhormidium Fott, were illegitimate or inadequate. Ultrastructural studies showed papilla formation during sporogenesis on cell wall, marking rupture point in zoospore release; cytokinesis by furrowing sometimes associated with array of ill-defined cytokinetic microtubules; flagellar root system in zoospores asymmetric, characterized by presence of a so-called MLS (multilayered structure). Accordingly, Klebsormidium associated with charophycean evolutionary line, this also supported by catalase activity of peroxisomes. Karyological studies indicate chromosome numbers of n= 22-26.
Klebsormidium occurs mostly in soil and on moist substrates but aquatic species are known; one species is marine.
Numbers of names and species: There are 24 species names in the database at present, as well as 6 infraspecific names. Of the species names, 17 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.
Skaloud, P. (2006). Variation and taxonomic significance of some morphological features in European strains of Klebsormidium (Klebsormidiophyceae, Streptophyta). Nova Hedwigia 83: 533-550.
Marin, B. & Melkonian, M. (1999). Mesostigmatophyceae, a new class of streptophyte green algae revealed by SSU rRNA sequence comparisons. Protist 150: 399-417, 9 figs, 2 tables.
Sluiman, H.J., Guihal, C. & Mudimu, O. (2008). Assessing phylogenetic affinities and species delimitations in Klebsormidiales (Streptophyta): nuclear-encoded rDNA phylogenies and ITS secondary structure models in Klebsormidium, Hormidiella, and Entransia. Journal of Phycology 44(1): 183-195.
Rysánek, D., Holzinger, A. & Skaloud, P. (2016). Influence of substrate and pH on the diversity of the aeroterrestrial alga Klebsormidium (Klebsormidiales, Streptophyta): a potentially important factor for sympatric speciation. Phycologia 55(4): 347-358.
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: 04 January 2015 by Paul Gabrielson
Linking to this page: http://www.algaebase.org/search/genus/detail/?genus_id=42757
Please cite this record as:
Paul Gabrielson in Guiry, M.D. & Guiry, G.M. 2019. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 24 January 2019.