Complete mitochondrial genome of Grey Treepie, Dendrocitta formosae (Aves: Corvidae).

We report the complete mitochondrial genome of Dendrocitta formosae. The genome is a closed circular molecule of 16,875 bp, with all genes exhibiting typical avian gene arrangement. The overall base composition of this species' mitogenome is 24.33% T, 30.49% C, 30.17% A, and 15.01% G. The A + T content is 54.50%. Phylogenetic analysis of the complete mitogenome of 12 species conducted using the neighbour-joining method and kimura 2-parameter model suggested that the mitogenome of D. formosae was the closest to that of Pyrrhocorax graculus and P. pyrrhocorax. The results could aid future studies on Dendrocitta and Pyrrhocorax molecular evolution and phylogeny.

Dendrocitta formosae, belonging to the family Corvidae (Aves, Passeriformes), is distributed in Bangladesh, Bhutan, China, India, Myanmar, Nepal, Pakistan, Thailand, Vietnam, and Laos (IUCN 2019). This species inhabits forests, shrublands, and arable lands (Mackinnon and Phillipps 2000). Because of the on-going habitat destruction on Hainan, China, the current population of this bird is declining (IUCN 2019). Relatively scarce information is available on the complete mitogenome of Dendrocitta species. Herein, we describe the complete mitogenome of Dendrocitta formosae.

We characterized the complete mitogenome of a D. formosae individual sampled in Jiangning District, Nanjing City, China (31.89°N, 118.76°E). Whole blood sample for genomic DNA extraction was collected from the individual and stored in the Forensic Identification Center for Forest Police of the State Forest Bureau. Genomic DNA was extracted using the DNAiso reagent (Takara, Beijing, China). A set of primers were designed for PCR, and Sanger sequencing based on the complete mitogenomes of Urocissa caerulea (GenBank accession: MG932654.1), Urocissa erythrorhyncha (GenBank accession: JQ423932.1), Pica pica (GenBank accession: HQ915867.1), and Corvus frugilegus (GenBank accession: Y18522.2).

The complete mitochondrial genome (GenBank accession: MK875763) of D. formosae is a typical circular DNA molecule of length 16,875 bp. The nucleotide composition is 24.33% T, 30.49% C, 30.17% A, and 15.01% G, with A + T content of 54.50%. The mitogenome consists of 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes, and one control region. The structure of the mitogenome is identical to that of most avian species (Caparroz et al. 2018; Liu et al. 2019; Sun et al. 2019).

Phylogenetic analysis of D. formosae was performed based on the complete mitogenome of 11 other birds. Sequence dataset was aligned using ClustalX and analyzed using the neighbour-joining method and the kimura 2-parameter model in MEGA 7.0, with 1000 bootstrap replicates (Kumar et al. 2016). The phylogenetic tree showed that the mitogenome of D. formosae was genetically the closest to that of Pyrrhocorax graculus and P. pyrrhocorax (Figure 1), which is in accordance with the current morphological classification. The genome information obtained herein could contribute to future studies on the molecular evolution and phylogeny of Dendrocitta and Pyrrhocorax.

Figure 1.

Neighbour-joining phylogenetic tree based on the complete mitogenomes of 12 avian species, constructed using MEGA 7.0.