Dysmorphococcus Takeda, 1916
Holotype species: Dysmorphococcus variabilis H.Takeda
Original publication and holotype designation: Takeda, H. (1916). Dysmorphococcus variabilis, gen. et sp. nov. Annals of Botany 30: 151-156.
Taxonomic status: currently recognized as a distinct genus.
Most recent taxonomic treatment adopted: Massjuk, N.P., Lilitska, G.G. & Kapustin, D.O. (2011). Chlamydomonadales. In: Algae of Ukraine: diversity, nomenclature, taxonomy, ecology and geography. Volume 3: Chlorophyta. (Tsarenko, P.M., Wasser, S.P. & Nevo, E. Eds), pp. 157-218. Ruggell: A.R.A. Gantner Verlag K.-G..
Description: Unicellular,biflagellate and uninucleate algae with protoplast contained within a firm,globose to ellipsoid lorica. Lorica slightly compressed and brown to verydark brown resulting from iron deposits. Lorica with fine pores,appearing granulate and occasionally ornamented otherwise. Flagellaanterior emerging from separate openings in apical papilla. Protoplastglobose to pyriform, not completely filling the lorica. Contractilevacuoles either two at base of flagella or several, irregularly distributedthroughout cytoplasm.Asexualreproduction by division into 2 or 4 daughter cells released afterfragmentation of mother cell lorica. When released, daughter cells do not have distinct lorica. Aplanospores reported. Sexual reproduction unknown.Unicellular,biflagellate and uninucleate algae with protoplast contained within a firm,globose to ellipsoid lorica. Lorica slightly compressed and brown to verydark brown resulting from iron deposits. Lorica with fine pores,appearing granulate and occasionally ornamented otherwise. Flagellaanterior emerging from separate openings in apical papilla. Protoplastglobose to pyriform, not completely filling the lorica. Contractilevacuoles either two at base of flagella or several, irregularly distributedthroughout cytoplasm.Asexualreproduction by division into 2 or 4 daughter cells released afterfragmentation of mother cell lorica. When released, daughter cells do not have distinct lorica. Aplanospores reported. Sexual reproduction unknown.
Information contributed by: G.E. Dillard. The most recent alteration to this page was made on 29 Nov 2017 by M.D. Guiry.
Comments: Dysmorphococcus spp. cosmopolitan in distribution and frequentlyencountered in freshwater phytoplankton, although rarely observed inabundance. The eight well described species differentiated based onnumber of pyrenoids and cntractile vacuoles present, the shape of the lorica,and the nature of ornamentation of the lorica (see Ettl 1983a for descriptionsand figures. A number of Dysmorphococcus spp. previouslyconsidered as species of Chlamydomonas or Thorakomonas.Dysmorphococcus> spp. grow well under aerobic conditions in thelight. However, in axenic culture aerobic growth is inhibited in mediasupplemented with propionate, cysteine, glutamic acid (@ 5 x10-4 M), histidineand phenylalanine. Acetate supports only slight growth under aerobicconditions in the dark. No growth occurs in anaerobic conditions in thedark, though anaerobic growth in the light occurred in mdium supplementedwith -ketoglutarate, pyruvate, and acetate. Good rowthrecovery obtained in some carbon supplemented media after several weeks ofincubation in the dark. However, citrate, alanine, propionate,asparagine, cysteine, histidine, lysine and glutamic acid at some cncentration,inhibited the recovery of dark-incubated cultures. InDysmorphococcus globosus lorica formation results from the following 1)secretion of immature envelope consisting of outer fibrous layer and innergranular layer; 2) sequential precipitation of mineralized component in innerlayer, during which time pores form; 3) exudation of mucilaginous materialsthrough these pores; and 4) localized secretion and subsequent retention ofsecretory product giving rise to pebbled appearance of lorica surface.Acetolysis of aplanospores suggests presence of sporopollenin in D. globosus.
Numbers of names and species: There are 12 species names in the database at present, as well as 1 infraspecific names. Of the species names, 10 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.
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: 11 April 2002 by M.D. Guiry
Verified by: 29 November 2017 by M.D. Guiry
Linking to this page: http://www.algaebase.org/search/genus/detail/?genus_id=43457
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 26 October 2021.