Triglochin maritima has been considered extinct in the Czech Republic until recently. The last herbarium specimens in Bohemia and Moravia were collected in the 1950s. In May 2000, three plants were discovered in a shallow ditch in the National Nature Reserve Slanisko u Nesytu near Sedlec (South Moravia). They grew in a loose stand of halophilous species approaching the brackish reeds of the association Bolboschoenetum maritimi.