Tolypella (A.Braun) A.Braun, 1857

Lectotype species: Tolypella nidifica (O.F.Müller) A.Braun

Original publication and holotype designation: Braun, A. (1857). Über Parthenogenesis bei Pflanzen. Abhandlungen der Koniglichen Akademie der Wissenschaften zu Berlin 1856: 311-376.

Request PDF

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 2024-07-09 by M.D. Guiry.

Taxonomic status: This name is of an entity that is currently accepted taxonomically.

Verification of Data
Users are responsible for verifying the accuracy of information before use, as noted on the website Content page.

Contributors
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.

Linking to this page: https://www.algaebase.org/search/genus/detail/?genus_id=43355

Citing AlgaeBase
Cite this record as:
M.D. Guiry in Guiry, M.D. & Guiry, G.M. 09 July 2024. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. https://www.algaebase.org; searched on 21 November 2024