Raillietiella affinis, a cephalobaenid pentastomid first described by Bovien (1927), from a Javanese gecko Gekko gecko, is shown to be a blunt-posterior hook species, a fact hitherto unrecognized. The species described as R. affinis by Self & Kuntz (1957) from a number of Egyptian desert lizards, is sharp-hooked and is a new species, Raillietiella aegypti. The type species of the taxon, R. geckonis (Diesing, 1850) Sambon, 1910 is a doubtful species, the true identity of which can never be known, and we propose that it should be excluded from use. We correct the many errors of identification that have appeared in the literature concerning these species.