In a previous paper, we reported on a large number of cheetah blood specimens that gave positive signals
only for Babesia and/or Theileria genus-specific probes on the reverse line blot (RLB) assay, indicating the
presence of a novel species or variant of an existing species. Some of these specimens were investigated further
by microscopic, serological, sequencing, and phylogenetic analyses. The near-full-length 18S rRNA genes of 13
samples, as well as the second internal transcribed spacer (ITS2) region, were amplified, cloned, and sequenced.
A species-specific RLB probe, designed to target the hypervariable V4 region of the 18S rRNA gene
for detection of the novel Babesia sp., was used to screen an additional 137 cheetah blood specimens for the
presence of the species. The prevalence of infection was 28.5%. Here we describe the morphology and phylogenetic
relationships of the novel species, which we have named Babesia lengau sp. nov.