Holotype species: Haplodasya reinboldii Falkenberg ex F.Schmitz & Falkenberg
Currently accepted name for the type species: Haplodasya urceolata (Harvey ex J.Agardh) M.J.Parsons
Original publication and holotype designation: Schmitz, F. & Falkenberg, P. (1897). Rhodomelaceae. In: Die natürlichen Pflanzenfamilien nebst ihren Gattungen und wichtigeren Arten insbesondere den Nutzpflanzen unter Mitwirkung zahlreicher hervorragender Fachgelehrten, Teil 1, Abteilung 2. (Engler, A. & Prantl, K. Eds), pp. 421-480. Leipzig: verlag von Wilhelm Engelmann.
Taxonomic status: currently recognized as a distinct genus.
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.
Description: Thallus an obligate epiphyte on Cystophora and Carpoglossum. Hemispherical holdfast embedded in host tissue; erect thallus, up to 20 cm long, monopodially branched, radially organized with corticated cylindrical polysiphonous axes with 5 (4 in some short branches or dwarf plants) pericentrals, each segment with a persistent, pigmented monosiphonous branched trichoblast. Surface cortical cells or pericentrals may produce adventitious simple or branched filaments resembling trichoblasts in H. tomentosa but not in H. urceolata (Parsons 1975) where they arise only from proximal cells of trichoblasts or their polysiphonous bases. Polysiphonous indeterminate branches originating by transformation of trichoblasts or similar adventitious filaments. Procarps develop proximally on trichoblasts or adventitious filaments; a 4-celled carpogonial branch and a single sterile cell group attached to the supporting cell. Two connecting cells formed after fertilization, one of which fuses with the auxiliary cell. Spermatangial capitula formed on unbranched trichoblasts or adventitious filaments, with 3 pericentrals per segment the fertile area enveloped by a single layer of spermatangial mother cells and terminated by 1-2 sterile cells. Tetrasporangial stichidia also formed on unbranched parts of trichoblasts and adventitious filaments; without trichoblasts on stichidia; 4 pericentrals formed, the 2nd becoming fertile. Two presporangial and 1 post-sporangial cover cell formed; tetrasporangia arranged in a single longitudinal row.
Information contributed by: R.E. Norris. The most recent alteration to this page was made on 7 Oct 2010 by M.D. Guiry.
Comments: Subtidal on hosts, Cystophora or Carpoglossum, Western Australia and southern Australian coast east to Victoria. Haplodasya differs from Lophothalia and Doxodasya in 1) formation of tetrasporangial stichidia from trichoblasts rather than polysiphonous ramuli and has no trichoblasts on the stichidium; 2) only 1 pericentral forms tetrasporangia in each stichidium segment; 3) tetrasporangia arranged in a longitudinal row rather than in decussate pairs or in a single row; lateral polysiphonous branches arise from conversion of entire trichoblasts rather than on a proximal branch.
Numbers of names and species: There are 3 species names in the database at present, of which 2 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: 28 December 2000 by M.D. Guiry
Linking to this page: http://www.algaebase.org/search/genus/detail/?genus_id=40447
Please cite this record as:
Guiry, M.D. & Guiry, G.M. 2021. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 22 January 2021.