A wide diversity of previously undetected free-living relatives of diplomonads isolated from marine/saline habitats
Abstract
We used culturing techniques to examine the diversity of free-living protists that are relatives of diplomonads, a group of evolutionary and parasitological importance. Until recently, a single organism, Carpediemonas membranifera, was the only representative of this region of the tree.
We report 18 new isolates of Carpediemonas-like organisms (CLOs) from anoxic marine sediments. Eleven isolates were classified within a new genus, Kipferlia n. gen.
The remaining isolates include representatives of three other lineages that likely represent additional undescribed genera (at least). Small subunit ribosomal RNA gene phylogenies show that CLOs form a cloud of six major clades basal to the diplomonad-retortamonad grouping.
CLOs will be valuable for tracing the evolution of diplomonad cellular features, for example, their extremely reduced mitochondrial organelles.