It appears
to be most similar to the white-spotted C. janthinoptera, a wide-ranging, Indo-Pacific species, which also inhabits
the Gambier Archipelago, and to the Hawaiian endemic C. jactator forming a species complex that exhibits
incomplete lineage sorting. Specimens of C. axiologus, or an undescribed but very similar sibling species, were
also collected at the Gambier Archipelago. Molecular analysis of these samples reveals an affiliation with C.
axiologus specimens collected from disjunct localities in the western Central Pacific. Canthigaster axiologus was
not previously known to occur east of the Tonga Islands. Geographic range expansions are also reported for C.
rapaensis and C. amboinensis.