3University of British Columbia, Department of Botany, V6T 1Z4 British Columbia, Vancouver, Canada; E-mail: firstname.lastname@example.org
4Canadian Institute for Advanced Research, ON M5G 1Z8 Toronto, Canada
5Masaryk University, Faculty of Science, Department of Botany and Zoology, 60177 Brno, Czech Republic; E-mail: email@example.com
6State Scientific Institute of Irrigation Fish Breeding, 142460 Vorovskogo Settlement, Noginsk District, Moscow Region, Russia; fax: + 7 (496) 513-7588; E-mail: firstname.lastname@example.org
* To whom correspondence should be addressed.
Received July 7, 2015
Phylogenetic analysis of large subunit ribosomal RNA (LSU rRNA or 28S rRNA) gene sequences from free-living predatory flagellates Colpodella angusta, Voromonas pontica, and Alphamonas edax (Apicomplexa) confirms their close relationship with chromerids Chromera velia and Vitrella brassicaformis, which possess a functional photosynthetic plastid. Together these organisms form a sister group to parasitic apicomplexans (coccidians and gregarines, or sporozoans sensu lato). This result agrees with the previous conclusion on monophyly of colpodellids and chromerids (chrompodellids) based on phylogenomic data. The revealed relationships demonstrate a complex pattern of acquisition, loss, or modification of plastids and transition to parasitism during alveolate evolution.
KEY WORDS: molecular phylogenetics, ribosomal RNA genes, apicomplexans, Sporozoa, heterotrophic flagellates, plastids, evolution of parasitism