The morphology of all juvenile stages of Eniochthonius minutissimus (Berlese, 1904) is redescribed and illustrated, that of the larva and successive nymphs of Hypochthonius rufulus C. L. Koch, 1835, is described and illustrated for the first time, and the ontogeny of both species is compared. These species differ mainly in the body shape, size and colour, the nature of transverse scissures on the dorsum of hysterosoma, the presence of the e-series setae, some setal formulae (gastronotal, genital, aggenital and segments PS-AN), and ontogeny of leg setation.