Multiple hypotheses of the biogeographical origins of such hypselostomatids have been supported by the authors: firstly, the isolation of populations may be a misconception, and be product of contiguous means of dispersal (cave systems or river drainages) of which only limited components have been studied; secondly, the distributions may be created by rare long-distance dispersal events; or thirdly, that the similarities between allopatric species are the result of convergent evolution.