Phylogeny and Taxonomic Revision of Plastid-Containing Euglenophytes based on SSU rDNA Sequence Comparisons and Synapomorphic Signatures in the SSU rRNA Secondary Structure

doi:10.1078/143446103764928521

Protist

Volume 154, Issue 1, April 2003, Pages 99-145

https://doi.org/10.1078/143446103764928521 Get rights and content

Summary

Sequence comparisons and a revised classification of the Euglenophyceae were based on 92 new SSU rDNA sequences obtained from strains of Euglena, Astasia, Phacus, Trachelomonas, Colacium, Cryptoglena, Lepocinclis, Eutreptia, Eutreptiella and Tetreutreptia. Sequence data also provided molecular signatures for taxa from genus to class level in the SSU rRNA secondary structure, revealed by a novel approach (search for non-homoplasious synapomorphies) and used for taxonomic diagnoses. Photosynthetic euglenoids and secondary heterotrophs formed a clade, designated as Euglenophyceae (emend.) with two orders: Euglenales and Eutreptiales. The mostly marine Eutreptiales (Eutreptia, Eutreptiella; not Distigma) comprised taxa with two or four emergent flagella (the quadriflagellate Tetreutreptia was integrated within Eutreptiella). The Euglenales (freshwater genera with ≤ one emergent flagellum) formed nine clades and two individual branches (single strains); however, only two clades were congruent with traditional genera: Trachelomonas (incl. Strombomonas) and Colacium. Euglena was polyphyletic and diverged into four independent clades (intermixed with Astasia, Khawkinea and Lepocinclis) and two individual branches (e.g. E. polymorpha). Phacus was also subdivided into Phacus s. str. and two combined lineages (mixed with Lepocinclis spp. or Cryptoglena). In consequence, Euglena (s. str.), Phacus and other genera were emended and one lineage (mixed Phacus/Lepocinclis-clade) was recognized as the previously neglected genus Monomorphina Mereschkowsky (1877). The sister clade of Phacus s. str. (mixed Euglena/Lepocinclis-clade) was identified as Lepocinclis Perty (emended).

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Phylogeny and Taxonomic Revision of Plastid-Containing Euglenophytes based on SSU rDNA Sequence Comparisons and Synapomorphic Signatures in the SSU rRNA Secondary Structure

Summary

Gene

Protist

FEMS Micobiol Lett

J Mol Biol

Gene

Protist

Mol Cells

Protist

from subtropical Argentina. Cryptogamie Algol

Arch Protistenkd

Mol Phylogenet Evol

Protist

Gene

Int Rev Cytol

Protist

Europ J Protistol

BioSystems

Eukaryotic diversity in Spain's river of fire

Nature

Remarks on Phacus and Euglena

Quart J Microscop Sci, Ser. 2

Cytological and taxonomic studies of the Euglenales. I. Ultrastructure and envelope elemental composition in Trachelomonas

Br Phycol J

Nuclear-encoded rDNA group I introns: origin and phylogenetic relationships of insertion site lineages in the green algae

Mol Biol Evol

Vertical evolution and intragenic spread of lichen-fungal group I introns

J Mol Evol

Archaea sister group of Bacteria? Indications from tree reconstruction artefacts in ancient phylogenies

Mol Biol Evol

Evaluating hypotheses on the origin and evolution of the New Zealand alpine cicadas (Maoricicada) using multiple-comparison tests of tree topology

Mol Biol Evol

Analysis of the primary sequence and secondary structure of the unusually long SSU rRNA of the soil bug, Armadillidium vulgare

J Mol Evol

Contributions to our knowledge of the genus Euglena

Sinensia

Neue und wenig bekannte Eugleninen und Volvocalen

Revue Algologique

Botanik, Bind II: Systematisk botanik, Nr. 2, Alger.

Algae

A taxonomic survey

Étude systématique du genre Lepocinclis PERTY

Mém Musée Royal d'Hist Nat Belg

The unusually long small-subunit ribosomal RNA of the crustacean, Daphnia pulex: sequence and predicted secondary structure

J Mol Evol

The divisions and classes of plants

Bot Rev

Contribuição para o conhecimento da fauna de Protozoarios do Brazil

II. Mem do Inst Oswaldo Cruz

Structural characterization of Eutreptia pertyi (Euglenophyta)

I. General description. Phycologia

Structural characterization of Eutreptia (Euglenophyta)

III. Flagellar structure and possible function of the paraxial rods. Phycologia

Ultrastructure of Pyramimonas cyrtoptera sp. nov. (Prasinophyceae), a species with 16 flagella from northern Foxe Basin, Arctic Canada, including observations on growth rates

Can J Bot

Remarques sur la systématique du genre Trachelomonas EHR

Bull Soc Bot France

Strombomonas, nouveau genre d'Euglénacées (Trachelomonas EHR. pro parte)

Arch Protistenkd

Description d'une Euglène nouvelle, Euglena mesnili nov

spec. Arch Zool Exp Gén; Notes et Revues

Freshwater algae of the southeastern United States. Part 7

Phylogeny of the bodonid flagellates (Kinetoplastida) based on small-subunit rRNA gene sequences

Int J Syst Evol Microbiol

A rapid DNA isolation procedure for small quantities of fresh leaf tissue

Phytochem Bull

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J Phycol