Abstract
A description of a meagerly known whip-scorpion species, “Trithyreus sawadai KISHIDA, 1930”, which is now regarded as a species of the genus Schizomus, is given for the first time. In spite of insufficient original treatment which was presented only by figures, the specific name has still validity in the Zoological Nomenclature. Originally this animal was found from “the Bonin Islands”, but this time it was exclusively discovered from Chichi-jima Island in the same Islands. It may be allied to “Trithyreus” luzonicus HANSEN known from Luzon in the Philippines, but can be distinguished by the shape of flagellum of both sexes from all the other “Trithyreus” hitherto known.