TreeBASE Search-Trees for study 1113

@ARTICLE{TreeBASE2Ref17494, author = {Woongghi Shin and Richard E. Triemer}, title = {Phylogenetic analysis of the genus Euglena (Euglenophyceae) with particular reference to the type species Euglena viridis.}, year = {2004}, keywords = {}, doi = {}, url = {}, pmid = {}, journal = {Journal of Phycology}, volume = {}, number = {}, pages = {}, abstract = {Euglena viridis (subgenus Euglena), serves as the type species for the genus Euglena. In this study, molecular phylogenetic analyses using an SSU and a combined SSU/partial LSU rDNA dataset for members of the genus Euglena showed that strains identified as E. viridis on the basis of morphology, are distributed between two separate, non-sister clades. Although all of the E. viridis strains examined were morphologically indistinguishable and possessed spherical mucocysts and stellate chloroplasts with one paramylon center, there was a high degree of sequence divergence between the E. viridis strains in different clades making this a cryptic species. Like E. viridis, all taxa from the subgenus Euglena, are characterized by having one or more stellate chloroplasts with paramylon grains clustered around the center of the chloroplast. These additional taxa divided into four clades in all of the molecular analyses. Strains of Euglena stellata formed two clades whose members had a single aggregate chloroplast with paramylon center and spindle-shaped mucocysts. A geniculata clade included species with one or two stellate chloroplasts with paramylon centers and spherical mucocysts and the cantabrica clade had members with one stellate chloroplast with paramylon center and spherical mucocysts arranged in a definite pattern. Interspersed among these, were three more clades bearing taxa from the subgenus Calliglena which contains members with discoid plastids with pyrenoids which may or may not be capped with paramylon. These taxa formed a laciniata clade , a mutabilis clade and gracilis clade. This study demonstrates that E. viridis and possibly E. stellata, are cryptic species that can only be distinugished at the molecular level. Because E. viridis is the designated type species for the genus Euglena, we designated an epitype for E. viridis.} }