The sheep ked Melophagus ovinus is mainly found in Europe, Northwestern Africa, and Asia. Although M. ovinus is an important ectoparasite of sheep in many countries, the population genetics, molecular biology, and systematics of this ectoparasite remain poorly understood. Herein, we determined the mitochondrial (mt) genome of M. ovinus from Gansu Province, China (MOG) and compared with that of M. ovinus Xinjiang Uygur Autonomous Region, China (MOX). The mt genome sequence (15,044 bp) of M. ovinus MOG was significantly shorter (529 bp) than M. o...