Comparing four mitochondrial genes in earthworms - Implications for identification, phylogenetics, and discovery of cryptic species

► COI and COII genes show higher intraspecific variation than 12S and 16S genes. ► The 12S rRNA and the 16S rRNA are valuable genes for earthworm identification. ► High genetic diversity in mtDNA underlines the need to revise earthworm taxonomy. ► Combining mitochondrial genes increases the reliability of phylogenetic analysis.