Plantago commersoniana is a rare and threatened species, with a highly disjunct distribution, mainly in southern Brazil. This study expands its distribution to Mato Grosso do Sul state, in the Central-West region of Brazil, due to the discovery of a collection of this species from rocky grasslands in Ponta Porã. This new record is ca. 285 km distant from the nearest known population, in Yhú, Caaguazú department, eastern Paraguay. This is also the first record of a native Plantago species in Mato Grosso do Sul. Its conservation status according to the IUCN criteria is Endangered (EN).