Tolypella (A.Braun) A.Braun, 1857
Lectotype species: Tolypella nidifica (O.F.Müller) Leonhardi
Original publication and holotype designation: Braun, A. (1857). Über Parthenogenesis bei Pflanzen. Abhandlungen der Koniglichen Akademie der Wissenschaften zu Berlin 1856: 311-376.
Taxonomic status: currently recognized as a distinct genus.
Most recent taxonomic treatment adopted: Bryant, J.A. & Stewart, N.F. (2002). Order Charales. In: The Freshwater Algal Flora of the British Isles. An identification guide to freshwater and terrestrial algae. (John, D.M., Whitton, B.A. & Brook, A.J. Eds), pp. 593-612. Cambridge: Cambridge University Press.
= Nitella subg. Tolypella A. Braun, Hooker's J. Bot. Kew Gard. Misc. 1: 194, 199. 1849 - (16 Dec 2019) - M.D. Guiry
Description: Morphology and development of vegetative thallus similar to Nitella. Genera different in aspect because of furcate branchlet growth in Nitella (absent in Tolypella), and the dense intercalary and terminal clusters of branchlets in Tolypella. Up to two-three indeterminate axes can develop in branchlet axes of any node. Asexual reproduction presumably similar to other Charae. Sexual reproduction always oogamous with unisexual or mostly bisexual plants producing lateral gametangia on branchlets. Antheridial morphology similar to that described for Lamprothamnion. Gametangia with two-celled stalks up to 1600 &m long (with stalk celled formed prior to subdivision of the antheridial mother cell) produced in clusters, in bisexual species mostly with 2-4 (-6) oosporangia associated with a single adaxial antheridium. Oosporangia with two, 5-celled tiers of crown cells. Mature oosporangia terete, oospores producing either one (section Acutifolia) or three sterile cells (section Obtusifolia). Life history presumably zygotic with meiosis occurring during oospore germination. Although the vegetative thallus is haploid, measurements of DNA in T. glomerata show that at least 70 % of nuclei have greater than 2C DNA. Chromosome counts carried out for over twelve taxa with counts ranging from n=8 in T. canadensis to n= 50 in T. salina; base numbers of 5, 8 and 11. Aneuploidy and polyploidization implicated in evolution of species. Tolypella cosmopolitan, mostly in freshwater with some species also in brackish water. Although there are many fewer species of Tolypella than either Chara or Nitella, Tolypella species tend to have much wider distributions with considerably less endemism. T. canadensis a supposed North America endemic recently reported from Scandinavia. Subfossil oosporangia can be identified from lake sediments. In some treatments Tolypella considered as a section of Nitella. Genus divided into two sections Acutifolia and Obtusifolia based on oospheres having either one or three sterile cells. Genus shares morphological similarities with Nitella and with Charae and may form ancestral complex from which other charophytes were derived. Sperm ultrastructure remains unstudied and should provide key information on relationships with Nitella, and with genera of Charae.
Information contributed by: D. Garbary. The most recent alteration to this page was made on 16 Dec 2019 by M.D. Guiry.
Numbers of names and species: There are 32 species names in the database at present, as well as 23 infraspecific names. Of the species names, 20 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: 16 December 2019 by M.D. Guiry
Linking to this page: http://www.algaebase.org/search/genus/detail/?genus_id=43355
Please cite this record as:
M.D. Guiry in Guiry, M.D. & Guiry, G.M. 2020. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 29 February 2020.