If the species is least concern according to IUCN red list, then why we go for mt-gene sequencing? What will be the usefulness for the species after research? Would it be the useful research or we should go for some other research topic?
Some cryptic species are hard to tell apart visually. Sequencing mitochondrial DNA is a more reliable way of identification. You can also use the mitochondrial sequences to build phylogenetic trees and in doing so can show how related populations are to each other.