The mitogenomes of Gelochelidon nilotica and Sterna hirundo (Charadriiformes, Sternidae) and their phylogenetic implications

Gelochelidon nilotica and Sterna hirundo are two sympatric breeding species. The mitogenomes of G. nilotica and S. hirundo are 16,748 bp and 16,707 bp in size. Both two mitogenomes reveal the same gene order and genomic organization to that of typical avian mtDNA. The first conserved blocks with a interrupted poly-C are present in the two species control regions, but not existed in S. albifrons. Seventeen and 11 simple sequence repeats are found in G. nilotica and S. hirundo, respectively. Phylogenetic analysis indicated that Sternidae has the closest relationship with Laridae. We supported that Stercorariidea is a sister group to (Alcidae (Laridae, Sternidae)), G. nilotica is genetically most related to S. hirundo (all belonged to Black cap species), but distant with S. albifrons (White blaze species) in kinship, and suggested that the status of Larus vegae should be further investigated.