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The green algae are a diverse group of primitive chlorophyll a
and b-containing eukaryotes that are commonly found in
the photic zones of freshwater, marine and terrestrial habitats.
The “Charophyceae” (Streptophyta, Viridiplantae)
represent a distinct assemblage within the green algae
from which all land plants evolved. The recognition
of the Charophyceaen Green Algae, or CGA, as a distinct group, was
first established during the 1970s-1980s (Mattox and Stewart 1984,
Pickett-Heaps, 1975) and was based on ultrastructural and biochemical
characteristics (e.g. flagellar appraratus structure, cell division
mechanisms). Over the past two decades, modern molecular research
has reconfirmed and refined earlier phylogenetic interpretations
and has elucidated taxonomic and phylogenetic classifications of
the taxa found within the specific subgroups of the CGA (Karol et
al. 2001, Lewis and McCourt 2004, Turmel and Lemieux 2006, McCourt
et al. 2004, Lemieux et al. 2007, Hall et al. 2008). Currently,
six extant groups are recognized in the CGA including the Mesostigmales,
the Chlorokybales,
the Klebsormidiales,
the Zygnematales,
the Charales and the
Coleochaetales.
For more references click CGA
References here or in the left navigation menu.
Subgroups of the CGA
The Charophyceae consist of six extant
clades or orders. To learn more about each group,
please click on the appropriate image below.
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