The box tree moth, Cydalima perspectalis (Walker, 1859) comb. n., is native to India, China, Korea, Japan and the Russian Far East. Its larvae are a serious pest of different species of Buxus. Recently, C. perspectalis was introduced into Europe and first recorded from Germany in 2006. This species has been placed in various spilomeline genera including Palpita Hübner, 1808, Diaphania Hübner, 1818, Glyphodes Guenée, 1854 and the monotypic Neoglyphodes Streltzov, 2008. In order to solve this nomenclatural confusion and to find a reasonable and verifiable generic placement for the box tree moth, the morphology of the above mentioned and some additional spilomeline taxa was investigated and their phylogeny analysed. The results show that C. perspectalis belongs to a monophylum that includes three of the genera in which it was previously placed: Glyphodes, Diaphania and Palpita. Within this monophylum, it is closely related to the Asian Cydalima Lederer, 1863. As a result of this analysis, Sisyrophora Lederer, 1863 syn. rev. and Neoglyphodes Streltzov, 2008 syn. n. are synonymised with Cydalima Lederer, 1863, and five species are transferred to this genus: Cydalima capriniodes (Hampson, 1912) (Glyphodes) comb. n., Cydalima decipiens (Hampson, 1912) (Glyphodes) comb. n., Cydalima joiceyi (Janse, 1924) (Margaronia) comb. n., Cydalima perspectalis (Walker, 1859) (Phakellura) comb. n. and Cydalima pfeifferae (Lederer, 1863) (Sisyrophora) comb. rev.