Geographical and biological considerations are examined with regard to the unique trans-Atlantic and trans-Mozambique Channel dispersal patterns of the Ethiopian genus, Opisthacanthus. It is concluded that the occurrence of this genus in the New World and Madagascar is the result of trans-oceanic rafting on driftwood. The Ethiopian Opisthacanthus lecomtei (Lucas, 1858) is placed in synonymy with the neotropical O. elatus (Gervais, 1805). Keywords: Arachnida, creeping scorpions, dispersal patterns, Opisthacanthus Peters, Scorpionidae, zoogeography.