 Only four species, all subterranean, have been described.Of the three genera, "Potiicoara" is known only from a cave in Brazil's Mato Grosso, "Spelaeogriphus" only from a cave on Table Mountain in South Africa, and the two "Mangkurtu" species only from individual Australian aquifers.This widely separated distribution implies an early origin for the group, hypothesised as emerging at least in the Tethys Sea around Gondwana.