The DR, together with #check details randurls[1|1|,|CHEM1|]# the DL, supported the dorsal-left side of the pocket, and the DMt supported the dorsal-right side. The VR – reinforced by the VL – lined the ventral side of the pocket and was in contact with the IR that lined

the ventral-left side of the flagellar pocket. The microtubules of the DMt and the VR became part of the elements forming the cytostomal funnel and accessory rod (i.e., the C-shape rod apparatus in general), and both the DR and the IR became part of the sheet of microtubules underlining the plasma membrane of the entire cell. Molecular Phylogenetic Position In order to infer the phylogenetic position of B. bacati, we PCR-amplified and sequenced the nearly complete SSU rDNA gene (2057 bp) from two independent isolates. The sequences contained expansions typical of euglenozoan SSU rDNA genes. First, we carried out a 40-taxon Maximum likelihood (ML) analysis that included sequences representing all of the major groups LY2109761 research buy of eukaryotes; the resulting phylogeny showed B. bacati grouped strongly within the

Euglenozoa (not shown). A second analysis included 37 taxa representing all of the major lineages of euglenozoans. The phylogenetic analyses showed that the euglenozoan sequences clustered in five main subgroups with high statistical support (Figure 12): (i) a kinetoplastid clade   (ii) a diplonemid clade   (iii) a bacteriovorous euglenid clade   (iv) a eukaryovorous + phototrophic euglenid clade and   (v) the Symbiontida, a newly named clade that includes Calkinsia aureus and several environmental sequences. Bihospites bacati clustered with the Branched chain aminotransferase Symbiontida with extremely high statistical support (ML bootstrap value = 100% and Bayesian posterior probability > 0.95), as the sister lineage to the rest of this group. Calkinsia aureus branched next within the Symbiontida and formed the sister lineage to several environmental sequences (Figure 12). However, the relationship of the Symbiontida to the other main

subgroups within the Euglenozoa was unclear.   Figure 12 Phylogenetic position of Bihospites bacati n. gen. et sp. within the Euglenozoa as inferred from small subunit (SSU) rDNA sequences. Maximum likelihood (ML) analysis of 35 euglenozoan taxa, rooted with two jakobids (Andalucia incarcerata and A. godoyi). Only ML boostraps greater then 50% are shown. Thick branches correspond to Bayesian posterior probabilities over 0.95. Ba, bacterivorous taxa; Eu, eukaryovorous taxa; Ph, photosynthetic taxa. Discussion Bihospites bacati n. gen et sp. possesses all three synapomorphies that unify the Euglenozoa: a tripartite flagellar root system, heteromorphic paraxial rods and tubular extrusomes. Concordantly, our analyses of SSU rDNA sequences clearly places B. bacati within the Euglenozoa, specifically within the Symbiontida. Several studies based on environmental sequences indicated the existence of a novel rDNA clade of euglenozoans [9–11].