Four species of the genus Tydeus are described and illustrated as new to science. T. ivoensis n.sp. and T. filiformis n.sp. were collected from moss layer on the soil surface, T. paravarsoviensis n.sp. and T. penicillatus n.sp. from lichens on twigs found on the soil surface. Paralorryia insignia Livshitz, 1973, P. carya Baker, 1968, Lorryia funki Baker, 1968 and L. polygonata Kulczycki, 1992 are all transferred to the genus Tydeus on the grounds of leg chaetotaxy. The female of T. funki is redescribed, based on the holotype, and a male, collected from Sweden, is described for the first time. The female of T. carya is described for the first time. Eight species are reported as new to Sweden. A key to adults of the twenty-four Tydeus species so far known in Southern Sweden is given.