Description of three eyeless and apigmented new species of Trichoniscidae which have been found in Su Mannau cave in Sardinia. Two of them belong to the genus Catalauniscus Vandel: Catalauniscus hirundinella n.sp. offering few relationships with the spanish species C. espanoli Vandel, and Catalauniscus puddui n.sp. which has also similar features to an iberian form, C. bolivari Arcangeli. The third (Scotoniscus janas n.sp.) belongs to the endemic genus Scotoniscus Racovitza, until now monospecific and represented by a series of subspecies from the Northern Pyrenees, all nearly related to the specific form S. macromelos Racovitza. The discovery of those three new species brings forward additional arguments to the thesis of a Tyrrhenian origin of these taxa of Trichoniscidae.