Phylogenetic position of Calkinsia aureus within euglenozoans as inferred from SSU rRNA gene sequences. Maximum likelihood (ML) analysis of 35 taxa focusing on the position of Calkinsia aureus within the Euglenozoa clade. Two jakobids, Andalucia incarcerata and A. godoyi, are used as outgroups in this analysis. ML bootstrap values greater than 50% are shown. Thick branches indicate Bayesian posterior probabilities over 0.95. Ba, bacteriotroph; Eu, eukaryotroph; Ph, phototroph. GenBank accession numbers of the sequences analyzed are shown in parentheses.