Assessment of Matourea pratensis (Plantaginaceae: Gratioleae) reveals an older name for Achetaria

Matourea pratensis is a name published by Aublet in 1775 that has never been typified and whose identity has long been obscure. It was historically associated with Stemodia foliosa , as S. pratensis , a species with reported medical importance and wide distribution in the Neotropics. However, its morphology has also been interpreted as more similar to Achetaria , a genus widely distributed throughout the Neotropics and also with medicinal, ecological and economic value. After an extensive bibliographical survey, along with morphological study of type specimens of M. pratensis , S. foliosa, and Achetaria spp., we conclude that (1) S. foliosa and M. pratensis represent distinct taxa; and (2) M. pratensis is congeneric with Achetaria . As a result, we transfer the currently accepted species of Achetaria to Matourea , proposing eight new combinations ( M. azurea , M. caparaoensis , M. crenata , M. erecta , M. latifolia , M. ocymoides , M. platychila , M. scutellarioides ). Additionally, we designate lectotypes for M. pratensis , Tetraplacus platychilus f. longifolius , Otacanthus caparaoensis , O. fluminensis , and O. villosus , and a second‐step lectotype for Beyrichia scutellarioides.