In a revision of four Eurydema speices recorded in Far East Asia, we confirm only two species, one of which consists of two subspecies: E. dominulus (Scopoli 1763) [=E. pulchra (Westwood 1837), syn. nov.], E. gebleri gebleri Kolenati 1846, and E. gebleri rugosa Motschulsky 1861 [stat. nov.]. In order to prove the above taxonomic changes, we compared three major characters; (1) the color patterns, (2) the mitochondrial COI (DNA barcoding) and (3) cross– breeding fertility (inter–specific copulation). Two subspecies, E. g. rugosa and E. g. gebleri, preserve their own unique coloration patterns, confirmed by the intra–subspecific copulation and breeding. Interestingly, the 1st progeny from the inter–subspecific copulation of E. g. rugosa♂ X E. g. gebleri♀ (or E. g. gebleri♂ X E. g. rugosa♀) take the coloration patterns inherited from E. g. gebleri.

Only two species of Eurydema occur in Korea and Japan: E. dominulus (Scopoli, 1763) [= E. pulchra (Westwood, 1837), syn. n.] and E. gebleri Kolenati, 1846 [= E. rugosa Motschulsky, 1861, syn. n.]. In order to prove the above taxonomical change, we focused on three major works (1)morphology, (2)molecular identification and (3)biological experiment (inter-specific copulation, confirmation of fertilization and interbreeding). All the results of these three major works support to confirm new taxonomical change amongst these four species. The inter-specific copulation occurs (E. pulchra_male X E. gebleri_female) in nature, but the eggs from inter-specific copulation are confirmed not to be fertilized as a result of the biological experiment. A new identification key to species occurring in Korea and Japan is presented for the all stages (from eggs to adult).