Morphological growth response of Draparnaldia (Chaetophoraceae; Chlorophyta) in culture
Acta botanica neerlandica , Volume 33 - Issue 2 p. 145- 149
Draparnaldia Bory is a genus of branched filamentous green algae which embraces about 20 species. Its distributional pattern includes stable to ephemeral fresh water habitats including acid or alkaline conditions. It is sensitive to pollution, hence it appears to be appropriate for the typification of natural fresh water systems. For example, in the saprobic system of Fjerdingstad (1964) Draparnaldia glomerata is employed as a biological indicator of oligosaprobic waters, while Draparnaldia plumosa defines water of katharobic status. Based on, e.g., ultrastructural grounds Draparnaldia together with Stigeoclonium, Fritschiella and Uronema constitute the very homogeneous Chaetophoraceae (Barker & Lokhorst in press, Lokhorst et al. in press). In its natural habitat, the alga demonstrates a conspicuous main axis consisting of barrel-shaped or cylindrical cells from which opposite, alternate or whorled fascicles of setiferous branchlets project (Prescott 1951). However, when this alga is brought into culture, its phenotypic plasticity is expressed by a gradual loss in ability to produce main axes, thereby giving rise to a Stigeoclonium-like growth habit (e.g., Carroll & Deason 1969; personal observations).
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