Previously, several levels of phylogenetic relationships in an insect order Odonata have been estimated using morphological and molecular markers. For the molecular phylogeny rRNA sequences were mainly, but other markers were not frequently employed. In this study, we sequenced both two mitochondrial genes (COI and 16S rRNA) and nuclear genes (28S rRNA and elongation factor-1α), composed of ~4,002 bp from 71 species of Odonata, occurring mostly in South Korea. These concatenated sequences were utilized to test the previous phylogenetic hypotheses of Odonata via Bayesian Inference (BI) and Maximum Likelihood (ML) algorithms, along with the data partition option available in BI method. Each families and superfamilies represented by multiple taxa consistently supported monophylies with the highest nodal supports in both Anisoptera and Zygoptera. A close relationship of Anisozygoptera to Anisoptera represented by a single species was obvious. On the other hand, familial relationships within each suborder of Anisoptera and Zygoptera have shown two compelling topologies. The topology obtained by BI method with partitioning of the four genes showed an unresolved relationship among Gomphidae, Aeshnidae, and the suborder Anisozygoptera in Anisoptera clade, presenting the relationships ((((Libellulidae + Corduliidae) + Macromiidae) + (Gomphidae + Aeshnidae + Anisozygoptera)) + (((Coenagrionidae + Platycnemdidae) + Calopterygidae) + Lestidae)). Another topology obtained by both BI and ML methods without partitioning, on the other hand, placed Anisozygoptera the basal lineage of Anisoptera, but Lestidae in Zygoptera was placed as the sister to Anisoptera + Anisozygoptera, presenting the relationships (((((((Libellulidae + Corduliidae) + Macromiidae) + Aeshnidae) + Gomphidae) + Anisozygoptera) + Lestidae) + ((Coenagrionidae + Platycnemdidae) + Calopterygidae)). Topological test to find out better supported tree turned out a slight higher support for the former topology, but the monophyly of Zygoptera with the inclusion of Lestidae was supported only poorly (BPP = 0.68) in the former topology.

The phylogenetic relationships among the Nymphalidae (Lepidoptera: Papilionoidea) have been controversial. The present study sequenced approximately 1,099 bp from cytochrome oxidase subunit I (COI), 1,336 ~ 1,551 bp from 16S ribosomal RNA (16S rRNA), and 1,066 bp from elongation factor-1 alpha (EF-1α) in 80 species belonging to seven subfamilies (Linmenitidinae, Heliconiinae, Nymphalinae, Apaturinae, Libytheinae, Satyrinae, and Danainae) of Nymphalidae, along with those of six lycaenid species as outgroups. The average base compositions for the three genes (COI, 16S rRNA, and EF-1α) are as follows: A (30.6%, 38.8%, and 25.8%), G (14.7, 5.2%, and 23.6%), T (39.8%, 45.2%, and 23.4%), and C (14.9%, 10.8%, and 27.3%). This result shows the A/T bias in the mitochondrial genes, but not for the nuclear EF-1α. Between the two mitochondrial genes, the 16S rRNA gene evidenced a significantly higher A/T content than was detected in the COI gene. These sequences were subjected to phylogenetic reconstruction via Bayesian Inference (BI) and Maximum Likelihood (ML) algorithms. Both analyses concordantly supported the subfamilial relationships of (((((Linmenitidinae + Heliconiinae) + (Nymphalinae + Apaturinae)) + Libytheinae) + Satyrinae) + Danainae), along with highly supported monophyletics of tribes within subfamilies. This result is largely consistent with a previous study performed with a large sequence information and morphological characters, except for the position of Libytheinae, which was suggested to be the basal lineage of Nymphalidae.