Structure and Phylogenetic Relationships of Scolopacidae Mitogenomes (Charadriiformes: Scolopacidae)

The family Scolopacidae presents a valuable subject for evolutionary research; however, molecular studies of Scolopacidae are still relatively understudied, and the phylogenetic relationships of certain species remain unclear. In this study, we sequenced and obtained complete mitochondrial DNA (mtDNA) from Actitis hypoleucos and partial mtDNA from Numenius arquata, Limosa limosa, and Limnodromus semipalmatus. The complete mtDNA contained 13 protein-coding genes (PCGs), two ribosomal RNA genes, 22 tRNA genes, and a control region. Scolopacidae contained three types of start codons and five types of stop codons (including one incomplete stop codon, T--). In 13 protein-coding genes, average uncorrected pairwise distances (Aupd) revealed that ATP8 was the least conserved while COX3 had the lowest evolutionary rate. The ratio of Ka/Ks suggested that all PCGs were under purifying selection. Using two methods (maximum likelihood and Bayesian inference) to analyze the phylogenetic relationships of the family Scolopacidae, it was found that the genera Xenus and Actitis were clustered into another sister group, while the genus Phalaropus is more closely related to the genus Tringa. The genera Limnodromus, Gallinago, and Scolopax form a monophyletic group. This study improves our understanding of the evolutionary patterns and phylogenetic relationships of the family Scolopacidae.