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

The phylogeny of kinetoplastid flagellates was investigated by determining the sequences of the small-subunit (18S) rRNA from Bodo designis, Bodo salt ans K, Bodo saltans P, Bodo sorokini, Bodo sp. (cf. uncinatus), Cruzella ma rina, Cryptobia helicis, Dimastigella mimosa and Parabodo nitrophilus and a nalysing these data together with several previously obtained sequences. Th e root of the kinetoplastid tree was tentatively determined to be attached to the branch of B, designis and/or Cruzella marina. Within this topology, the suborder Trypanosomatina appears as a late-emerging monophyletic group, while the suborder Bodonina is paraphyletic. Within the bodonid subtree, t he branches of parasitic organisms were intermingled with free-living ones, implying multiple transitions to parasitism. The tree indicates that the g enera Cryptobia and Bodo are artificial taxa. In addition, the separation o f the fish cryptobias and Trypanoplasma borreli as different genera was not supported.