Spermatochnus Kützing, 1843, nom. cons.
Holotype species: Spermatochnus paradoxus (Roth) Kützing
Original publication and holotype designation: Kützing, F.T. (1843). Phycologia generalis oder Anatomie, Physiologie und Systemkunde der Tange. Mit 80 farbig gedruckten Tafeln, gezeichnet und gravirt vom Verfasser. pp. [part 1]: [i]-xxxii, [1]-142, [part 2:] 143-458, 1, err.], pls 1-80. Leipzig: F.A. Brockhaus.
Request PDFDescription: Thallus erect, cylindrical, branched, to 50 cm high. Medulla a single leading filament and whorls of 4 to 5 lateral cells from each axial cell. Growth by means of a single dome-shaped meristematic apical cell. Cortex to 4 cells thick, with an outermost dense layer of small cells resulting in a smooth thallus surface. Two kinds of assimilatory filaments present. Primary assimilatory filaments formed in whorls near apex but do not obscure the apical cell. Secondary assimilatory filaments formed in tufts on thallus surface.Phaeophycean hairs present. Unilocular sporangia ovoid, sessile, formed within tufts of secondary assimilatory filaments. Plurilocular sporangia rare, uniseriate, with few loculi, among secondary assimilatory filaments. Life history diplohaplontic with macroscopic sporophyte ***(2n40) and a monoecious microscopic gametophyte (n~20) that produces isogametes in uniseriate plurilocular gametangia. There is a temperature effect involved in gametogenesis: at 20%C, gametophytes produce asexual zoids, at 9%C they form gametes. The zygote develops into a few-celled erect uniseriate filament with terminal hyaline hair and basal cell proliferations. The meristematic apical cell of the macrothallus is formed secondarily from these proliferations. Fertile cultures of Spermatochnus paradoxus produce the unsaturated hydrocarbon, finavarrene, known as sexual pheromone in other brown algae, but attempts to demonstrate sexual attraction of gametes were unsuccessful. Distributed in the Mediterranean, on western Atlantic coasts, and in southern Australia.
Information contributed by: A. F. Peters. The most recent alteration to this page was made on 2015-10-19 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 masculine.
Most recent taxonomic treatment adopted: Silberfeld, T., Rousseau, F. & Reviers, B. de (2014). An updated classification of brown algae (Ochrophyta, Phaeophyceae). Cryptogamie Algologie 35(2): 117-156, 1 fig., 1 table.
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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=32912
Citing AlgaeBase
Cite this record as:
M.D. Guiry in Guiry, M.D. & Guiry, G.M. 19 October 2015. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. https://www.algaebase.org; searched on 22 November 2024
