The mitochondrial genomes of the endemic and endangered South Philippine Hawk-eagle Nisaetus pinskeri and other Nisaetus Hawk-eagles (Aves, Accipitriformes)

Southeast Asia is home to 22 endemic raptors, and almost all are classified as "Endangered" or higher by the International Union for Conservation of Nature and Natural Resources (IUCN). The limited range and fragmented distribution of some Southeast Asian raptors from the genus Nisaetus hinder the characterization of these endangered birds. This study presents the mitochondrial sequences of the Pinsker's Hawk-eagle (Nisaetus pinskeri) and Changeable Hawk-eagle (Nisaetus cirrhatus) and conducts a comparative mitogenome analysis across Accipitriformes. The partial mitogenome lengths of N. pinskeri and N. cirrhatus are 18,654 bp and 17,874 bp, with a GC content of 46.4% and 47.4%, respectively. An extra cytosine at position 174 of the nad3 gene was present in both mitogenomes, which was not previously observed in other Nisaetus species. Phylogenetic analysis recapitulated the topology of the order Accipitriformes. It showed that N. pinskeri and N. cirrhatus are closely related to each other and sister to the rest of the Nisaetus representatives. Moreover, the trees based on concatenated mitochondrial protein-coding genes were closer to the latest reported phylogenies than single-gene trees using conventional mitochondrial markers. The selection pressure analysis showed that all protein-coding genes experienced purifying selection, with the highest in atp8 and the lowest in cox1. As the first report of the near-complete mitogenomes of these raptors, this study expands the available genomic resources for these understudied raptors and provides a foundation for future population genetic research.