Dasysiphonia I.K.Lee & J.A.West, 1980
Holotype species: Dasysiphonia chejuensis I.K.Lee & J.A.West
Original publication and holotype designation: Lee, I.K. & West, J.A. (1980 '1979'). Dasysiphonia chejuensis gen et sp. nov. (Rhodophyta, Dasyaceae) from Korea. Systematic Botany 4: 115-129.
Request PDFDescription: Thallus erect or prostrate and spreading, sympodially developed, dorsiventrally organized, the upright portions and tips plumose. Indeterminate axes terete, irregularly branched and alternately producing determinate pseudolateral branch systems (ramelli) from each polysiphonous segment. Pseudolaterals pigmented, distichously placed, and monosiphonous throughout, once to several times alternately to subdichotomously branched. Axial cells surrounded by 5 periaxials, with or without light to heavy rhizoidal cortication.
The type species has a typical Polysiphonia-type life history with isomorphic gametophytes and sporophytes and occasional mixed-phase reproduction in culture (Lee & West 1979, Choi & Lee 1996). Other species known only as tetrasporophytes (Schneider 1989). Plants dioecious, spermatangia formed in several successive whorled series on monosiphonous stalks of pseudolaterals, overall forming organized linear to lanceolate stichidia with sterile tips. Procarps formed on special polysiphonous branches in the upper portions of main axes on the female plant, these also bearing monosiphonous branches with long hair-like tips. Procarps consist of a 4-celled carpogonial branch and 2 sterile groups of cells borne on the supporting cell. After fertilization, the auxiliary cell is cut off the supporting cell, fuses with the carpogonium and generates monopodial gonimoblast filaments with terminal, then lateral carposporangia. Carposporophytes surrounded by large, corticated pericarps with obvious ostioles. Five tetrahedral sporangia produced in successive whorls on pseudolaterals, forming linear-lanceolate stichidia with sterile tips. Tetrasporangia only partially enclosed by cover cells at maturity.
Information contributed by: C.W. Schneider. The most recent alteration to this page was made on 2024-06-21 by Salvador Valenzuela Miranda.
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: Schneider, C.W. & Wynne, M.J. (2007). A synoptic review of the classification of red algal genera a half a century after Kylin's "Die Gattungen der Rhodophyceen". Botanica Marina 50: 197-249.
Comments: Unlike the three other known species, Dasysiphonia okiensis shows the formation of exogenous adventitious polysiphonous lateral branches from the basal cells of pseudolaterals and indeterminate branches in lower portions of main axes (Kajimura 1992). A rarely collected genus of subtropical waters in South Korea, Japan and southeastern U.S.A. Using a computer modeling system to graphically represent accurate branching patterns, Schneider et al. (1994) showed that minute differences might have occurred to allow the divergence of Dasya and Dasysiphonia.
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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=42510
Citing AlgaeBase
Cite this record as:
Salvador Valenzuela Miranda in Guiry, M.D. & Guiry, G.M. 21 June 2024. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. https://www.algaebase.org; searched on 21 November 2024
