The taxonomic position of Mecysmoderes consularis Pascoe (Mecysmoderini, subfamily Ceutorhynchinae) was studied. Based on morphological and biological reasons, M. consularis should be placed within the genus Xenysmoderes Colonnelli (also Mecysmoderini). The structures of the frons, prothorax, elytral intervals, and procoxae of X. consularis (Pascoe), new combination, agree well with those of Xenysmoderes species. The host plant association with the genus Alpinia Roxburgh (Zingiberales: Zingiberaceae) indicate closer relation to Xenysmoderes, which is associated with Costaceae (Zingiberales), rather than to Mecysmoderes Schoenherr, which is associated with trees of Ericaceae (Ericales). Xenysmoderes ruficollis, new species, is described from Lanhsu Island and is distinguished from X. consularis by the body coloration, pattern of scales, and shapes of male aedeagus and female spermatheca. Xenysmoderes consularis and X. ruficollis occur allopatrically, the former distributed in Taiwan proper and on Lutao Island, while the latter is found only on Lanhsu Island.