Kornmannia Bliding, 1969

Holotype species: Kornmannia leptoderma (Kjellman) Bliding

Original publication and holotype designation: Bliding, C. (1969 '1968'). A critical survey of European taxa in Ulvales, Part II. Ulva, Ulvaria, Monostroma, Kornmannia. Botaniska Notiser 121: 535-629, 47 figs.

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Description: Life history heteromorphic with gametophytic thalli consisting of microscopic, crustose, filamentous plants; sporophytes upright monostromatic leafy blades 1-2 cm or up to 10 cm in height. Basal system of blades discoid, developing from prostrate filaments. Blades usually formed by upheaval of sac from prostrate system, but occasionally develop from uniseriate filaments produced by crust. Blade differentiated into stipe region with elongate cells commonly with rhizoidal processes, cells in distal portion of blade polygonal and isodiametric, usually about 5 &m (-9) in diameter. In saccate stages cells in linear files, increasingly random with blade maturation. Gametophytic plants a microscopic pseudoparenchymatous disc. Cells with single nucleus and large parietal chloroplast without apparent pyrenoid using light microscopy. Ultrastructurally pyrenoids single per cell and ellipsoidal, without a starch sheath and without traversing thylakoids, but bound by thylakoid membranes. Asexual reproduction by means of zoospores produced on sporophytic blades. Sporangia formed from vegetative cells. Zoospores 4-5 &m long; without eyespot. Spores develop into new new sporophytic plants or into gametophytes. Maximum release during spring tides. Sexual reproduction by monoecious isogametes, these ca 4 &m and biflagellate, produced on crustose plants. Life history highly variable and population specific; Atlantic populations asexual, Pacific populations asexual and sexual. Kormannia widely distributed in temperate waters of the the North Atlantic and North Pacific Oceans; occasioanly in freshwater in high ionicor hard water conditions. Typically epiphytic on seagrasses (hence K. zostericola = K. leptoderma) it can also be found on red and brown seaweeds. Culture experiments show that temperature and daylenght can modify ontogeny and reproductive patterns. Protocols for the development of viable protoplasts have been developed such that protoplasts regeneate walls and develop into new blades. Two additional species have been recognized in Kornmannia (K. zostericola and Monostroma aereolatum), however, all isolates extremely similar in culture with variation in presence of sexuality, and host, blade size and shape. Further study required to adequately distinguish among them. Kornmannia only genus in family.

Information contributed by: D. Garbary. The most recent alteration to this page was made on 2014-12-28 by M.D. Guiry.

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

Gender: This genus name is currently treated as feminine.

Most recent taxonomic treatment adopted: Golden, L. & Cole, K.M. (1986). Studies on the green alga Kornmannia (Kornmanniaceae fam. nov., Ulotrichales) in British Columbia. Japanese Journal of Phycology 34(4): 263-274, 13 figs.

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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=38356

Citing AlgaeBase
Cite this record as:
M.D. Guiry in Guiry, M.D. & Guiry, G.M. 28 December 2014. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. https://www.algaebase.org; searched on 25 April 2024