Three Tolypella species ( T. glomerata , T. intricata and T. prolifera ) have been recorded in Belgium, all of them only sparingly and with most observations dating from the 19th C. We document new records of T. glomerata and T. intricata from stagnant fresh water in the Flemish region and discuss the general ecology and distribution of these rare species, as well as possibilities for site management. Three sites are small, more or less periodic water bodies, where either T. glomerata or T. intricata occur as winter-spring annuals, a fourth one is a stratified sand extraction pit where T. intricata grows at considerable depth. Extensive cattle grazing and trampling sustains T. glomerata in a wet polder grassland influenced by brackish seepage and continuation of this management is recommended. Both other sites with this species, a shallow pond and a ditch-like depression, are of more recent origin and the species is likely to have arrived here by bird transport or revitalisation of buried oospores. ...