A Synopsis, New Combinations, and Synonyms in Acanthocladus (Polygalaceae)

A synopsis of the American genus Acanthocladus Klotzsch ex Hassk. (Polygalaceae), based primarily on herbarium studies, is presented, along with an identification key to the currently accepted eight species. Two new synonyms and the following new combinations are presented: A. dukei (Barringer) J. F. B. Pastore & D. B. O. S. Cardoso, A. pulcherrimus (Kuhlm.) J. F. B. Pastore & D. B. O. S. Cardoso, and A. santosii (Wurdack) J. F. B. Pastore & D. B. O. S. Cardoso. The names A. brasiliensis Klotzsch ex Hassk. and A. pulcherrimus are lectotypified.