Ancyromonadida: a new phylogenetic lineage among the protozoa closely related to the common ancestor of metazoans, fungi, and choanoflagellates (Opisthokonta).

摘要: Molecular and morphological evidence points to the ancyromonad Ancyromonas as a plausible candidate for closest relative common ancestor of metazoans, fungi, choanoflagellates (the Opisthokonta). Using 18S rDNA sequences from most major eukaryotic lineages, maximum-likelihood, minimum-evolution, maximum-parsimony analyses yielded congruent phylogenies supporting this hypothesis. Combined with ultrastructural similarities between opisthokonts, presented here suggests that may form an independent lineage, Ancyromonadida Cavalier-Smith 1997, closer in its relationship opisthokonts than is nearest protist relatives, Apusomonadida. However, very low bootstrap support deep nodes hypothesis testing indicate resolving power limited examining aspect phylogeny. Alternate branching positions lineage cannot be robustly rejected, revealing importance ultrastructure when origins multicellularity. The future use multigene approach additionally needed resolve