Peperomia penicillata has been proposed as a synonym of Peperomia dominicana (Liogier 1996: 376), an erect plant with more robust stems, and of Peperomia septemnervis (Saralegui 2004: 15), with thicker and wider leaves. Peperomia penicillata deserves the status of 'accepted name' [Mathieu, 2006, pers. comm.]