When Dietrich published Peperomia cordifolia A.Dietr. he clearly mentioned his intention to transfer Piper cordifolium Sw. to the genus Peperomia (A. Dietrich, Species Plantarum 1: 154, 1831). However, the specific epithet ‘cordifolia’ was not available in Peperomia because of its publication by Opiz three years earlier. To circumvent this, Dietrich published Peperomia opiziana A.Dietr. and placed Peperomia cordifolia Opiz in its synonymy (l.c.: 162). In his view this made the specific epithet ‘cordifolia’ in Peperomia available again. Although this scenario might have been in accordance with the rules at that time it is not in accordance with the current nomenclatural uses. For this reason the name Peperomia cordifolia (Sw) A.Dietr. has to be considered as a later homonym. Nevertheless, P. cordifolia (Sw.) A.Dietr. is still in use as would it be a legitimate name and until now no author has taken action to correct this situation. In a series of publications as well as in herbarium specimens at B, BM, BR, CM, G, K, M, MICH, MO, P, PH, S, U, UPS the name is applied as legitimate. P. cordifolia (Sw.) A.Dietr. is a candidate ‘nomen conservandum’ against P. cordifolia Opiz [Mathieu 2011, pers. comm.]