Molecular Systematics of the Green Algae

Phylogenetic affinities of the Trentepohliales inferred from small-subunit rDNA

“…Our results do not support the concept of Sluiman (1989) that includes representatives of the Pleurastrales (pleurastrophycean algae sensu Mattox & Stewart, 1984) within the Ulvophyceae. Similar results based on cladistic analysis of nuclear rDNA sequence data have been reported by Kantz et al (1990) and reviewed by Chapman et al (1999).…”

“…Chapman et al, 1999;Waters & Chapman, 1996) of analyses of the nuclear-encoded smallsubunit (SSU) rDNA as well as the chloroplast-encoded large-subunit Rubisco gene (rbcL) provide support for the original suggestion, based on ultrastructural data, that there are two main lineages among the green plants (Pickett-Heaps & Marchand, 1972). One of the lineages comprises the charophycean algae and their descendents, the land plants (charophycean lineage sensu Pickett-Heaps & Marchant, 1972), forming a monophyletic group named Streptophyta (sensu Cavalier-Smith, 1993).…”

“…The second lineage (chlorophycean algae sensu Pickett-Heaps & Marchant, 1972) consists exclusively of the remaining green algae (containing at least Chlamydomonas and its allies, the coccoid green algae, Dasycladales, Cladophorales and Trebouxiophyceae), forming the monophyletic group Chlorophyta (sensu Cavalier-Smith, 1993;Friedl, 1997;Melkonian et al, 1995). The term 'chlorophyte' has often been used to denote all green algae; however, it should now be used only as an informal designation for green algae in the Chlorophyta [see Chapman et al (1999) for a revisionary approach to the systematics of the green algae].…”

“…The second lineage (chlorophycean algae sensu Pickett-Heaps & Marchant, 1972) consists exclusively of the remaining green algae (containing at least Chlamydomonas and its allies, the coccoid green algae, Dasycladales, Cladophorales and Trebouxiophyceae), forming the monophyletic group Chlorophyta (sensu Cavalier-Smith, 1993;Friedl, 1997;Melkonian et al, 1995). The term 'chlorophyte' has often been used to denote all green algae; however, it should now be used only as an informal designation for green algae in the Chlorophyta [see Chapman et al (1999) for a revisionary approach to the systematics of the green algae].Conflicting hypotheses have been offered about the systematic position of the Trentepohliales among the several classes of green algae. The presence of multilayered structures in the flagellar apparatus and the demonstration of a phragmoplasttype cytokinesis in Cephaleuros parasiticus (Chapman & Henk, 1986) and Trentepohlia odorata (Chapman et al, 2001;Waters et al, 1998) suggest an affinity with the class Charophyceae.…”

Phragmoplast-mediated cytokinesis in Trentepohlia: results of TEM and immunofluorescence cytochemistry.

“…Over the last decade, molecular studies have shown that (1) green algae and land plants share a common ancestor, (2) there are two major lineages of green algae, the charophycean and chlorophycean, and (3) the charophycean green algae are the closest relatives to the land plants (Chapman et al, 1998 ;Graham, 1993 ;Graham & Kaneko, 1991 ;Huss & Kranz, 1997 ;Kranz et al, 1995 ;Manhart, 1994 ;McCourt, 1995 ;Mishler et al, 1994). Some charophycean green algae have a phragmoplast-type cell division, the type basic to all land plants.…”