Parallela Flint: its phylogenetic position in the Chlorophyceae and the polyphyly of Radiofilum Schmidle

Phylogeny and Molecular Evolution of the Green Algae

“…Molecular phylogenetic analyses of nuclear ribosomal DNA and chloroplast sequences have profoundly changed the concept of the class, which now includes a diverse range of taxa formally placed in the Dunaliellales, Chlorococcales, Tetrasporales, Chlorosarcinales, Volvocales and Chaetophorales Wilcox et al, 1992;Buchheim et al, 1994;Nakayama et al, 1996a;Nakayama et al, 1996b;Booton et al, 1998b;Krienitz et al, 2003;Lewis & McCourt, 2004;Watanabe et al, 2006a;Watanabe et al, 2006b;Nakada et al, 2008a;Nakada et al, 2008b). As presently conceived, the class includes non-motile or motile unicells with two or four flagella, biflagellate colonies, filaments and cells that are imbedded in a mucilage envelope (Nakazawa et al, 2004;Nozaki et al, 2006b;Yamada et al, 2008;Nakada & Nozaki, 2009;Matsuzaki et al, 2010;Novis et al, 2010;Nozaki et al, 2010). The Chlamydomonadales mainly comprise freshwater and terrestrial green algae, including several psychrophilic and/or halotolerant species (e.g., Dunaliella and Chlamydomonas nivalis) (Eddie et al, 2008;Buchheim et al, 2010;Muramoto et al, 2010;Remias et al, 2010).…”

Filamentous (Nonconjugating) and Plantlike Green Algae

“…Of the three species currently recognized in AlgaeBase (Guiry and Guiry, 2014, searched 6 August 2014) only one (Radiofilum flavescens G.S. Novis et al (2010) showed that the type species (Radiofilum conjunctivum Schmidle) belongs to the Class Trebouxiophyceae and is closely related to the genus Microthamnion. It was long believed that Radiofilum, as traditionally circumscribed, was a heterogeneous assemblage of species with different ultrastructural features.…”

Inclusion of chloroplast genes that have undergone expansion misleads phylogenetic reconstruction in the Chlorophyta

“…The phylogenetic position of the new strains targeted for rpoB sequencing was confirmed using a data set of concatenated partial sequences of the chloroplast proteins AtpB, PsaB, and RbcL. Those strains for which data from some or all of the genes encoding these proteins were unavailable were sequenced using the protocol described by Novis et al (2010). Taxa for which sequences of AtpB and PsaB were not previously available, but were already maintained in our culture collection and are described elsewhere, are Chlamydomonas pseudogloeogama strain LCR‐T2A (Novis et al, 2008), Bracteacoccus ruber strain LCR‐CG8 (Novis and Visnovsky, 2012), Stichococcus sp.…”

“…Two overlapping fragments of the rpoB gene were sequenced from selected new taxa. The first spanned the conserved region corresponding to amino acid residues 438–615 in the Chlorella vulgaris RpoB protein, and was successfully sequenced in Chlamydomonas pseudogloeogama strain LCR‐T2A, Pseudomuriella engadinensis strain CCAP221/4, B. ruber strain LCR‐CG8, Parallela transversale strain SAG27.83, P. novae‐zelandiae strain Liffey (Novis et al, 2010), Chloromonas reticulata strain LCR‐CC18‐1A, Prasiola sp. strain Hallet (Moniz et al, 2012), Raphidonema nivale strain CU236c, Trebouxia sp.…”