The complete mitochondrial genome (mitogenome) of the butterfly, Euripus nyctelius, was determined in the present study. The mitogenome is a typical circular DNA molecule of 15,417 bp, containing 37 genes and a putative control region. Thirteen protein-coding genes all initiate with ATN codons and mostly terminate with TAA or TAG codons except for COII, ND4 and ND5 use a single T residue as the termination codon. All tRNAs have the classic clover-leaf structure, except that the dihydrouridine (DHU) arm of tRNA(Ser(AGN)) forms a simple loop. Both maximum likelihood and Bayesian analyses support the monophyly of butterflies and recover high supports for the following family level relationships: (Papilionidae + (Hesperioidea +(Pieridae (Lycaenidae + Nymphalidae)))). Euripus nycteliusis is placed as sister to the genus Sasakia within Nymphalidae.
Keywords: Apaturinae; Lepidoptera; Nymphalidae; mitochondrial genome.