Tapeinodasya Weber-van Bosse (Ceramiales, Rhodophyta): redescription of an enigmatic genus of the Dasyaceae
De Clerck, O.; de Jong, Y.S.D.M.; Coppejans, E. (2002). Tapeinodasya Weber-van Bosse (Ceramiales, Rhodophyta): redescription of an enigmatic genus of the Dasyaceae. Constancea 83: 83.10
In: Constancea: University of California Electronic Publications in Botany. University of California: Berkeley. ISSN 1559-4041, meer
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Auteurs | | Top |
- De Clerck, O., meer
- de Jong, Y.S.D.M.
- Coppejans, E., meer
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Abstract |
The genus Tapeinodasya, originally described by Weber-van Bosse (1904) from Indonesia and the Sulu Archipelago (Philippines), has remained one of the least known genera of the Dasyaceae. Based on recent collections from the East African coast, vegetative and tetrasporangial structures are described in detail for the first time and the placement of genus Tapeinodasya in the Dasyaceae based on cellulosympodial growth is confirmed. The genus is separated from all other genera of the Dasyaceae by a distinctive cauliflower-like habit, complete absence of monosiphonous filaments, extensively corticated tetrasporangial stichidia and the presence of both pre- and postsporangial cover cells. genus Tapeinodasya appears to be related to the Heterosiphonia-like genera, based on an alternate sequence of periaxial cell formation, a primary alternate- distichous arrangement of holoblastic branches, and branches separated from one another by one or more unbranched segments. Placement of genus Tapeinodasya in a clade with Thuretia and Dictyurus as recently hypothesized is verified by the recognition of a clockwise mode of alternate periaxial cell formation and a primary bilateral organisation. Comparison of the East African specimens with the type collections of the other known species, shows that the Tanzanian specimens belong to the Indonesian Tapeinodasya bornetii rather than to T. etheliae which was described from the Amirante Islands. The presence of T. bornetii in Tanzania represents a substantial range extension and a new record for the Indian Ocean. |
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