The northern and southern populations of a songbird species called the Godlewski’s bunting (Emberiza godlewskii) should be treated as two independent species: Emberiza godlewskii and Emberiza yunnanensis, according to new research led by Lanzhou University ornithologists.
The Godlewski’s bunting (Emberiza godlewskii) in Ulaanbaatar, Mongolia. Image credit: Jargal Lamjav / CC BY 2.0.
The Godlewski’s bunting is a species in the family Emberizidae, a group made up of seedeaters with conical bills.
First described in 1874, it has an extremely large range: China, Pakistan, India, Kazakhstan, Mongolia, Myanmar, and Siberia.
“The Godlewski’s bunting, Emberiza godlewskii, is widely distributed in East Asia,” said first author Dr. Jiande Li, a researcher at Lanzhou University and Northwest Normal University, and colleagues.
“It was previously considered conspecific to the rock bunting, Emberiza cia, which is distributed from Central Asia and the western Himalayas through southern Europe to northwestern Africa.”
“The species boundary between Emberiza cia and Emberiza godlewskii has been debated due to the interpretation of morphological variation among geographic populations.”
“Previously, in a study on the phylogeographic pattern of Emberiza godlewskii, we revealed a deep genetic divergence between the northern and southern subspecies,” they added.
“However, phylogenetic relationships between the two lineages of Emberiza godlewskii and Emberiza cia, as well as their phylogenetic position to the closest outgroup, Emberiza cioide, remain uncertain.”
In their new study, the researchers reconstructed the phylogenetic relationships of all Emberiza godlewskii subspecies across their distribution range.
“By comparing the morphological measurements and plumage color from all subspecies of the Emberiza godlewskii/Emberiza cia complex, we further delimitated the species boundary based on integrative evidence,” they said.
Their results show that the species Emberiza cia is the sister group of a clade composed of the northern populations of Emberiza godlewskii.
The southern populations of Emberiza godlewskii, known as the subspecies Emberiza godlewskii yunnanensis, should be elevated to species status.
Named Emberiza yunnanensis (common name – the south rock bunting), this bird is between 15.1 and 16.5 cm in length, and weighs between 16 and 21 grams.
It differs from Emberiza godlewskii in having a significantly darker colored belly. The body size of the males is slightly larger to that of the females.
Emberiza yunnanensis occurs on dry and rocky hilly slopes, karst forests, and wooded ravines in southwestern China.
It contains three subspecies: Emberiza yunnanensis styani, Emberiza yunnanensis khamensis, and Emberiza yunnanensis yunnanensis.
“Our research provides direct evidence of cryptic species in Old World buntings,” the authors concluded.
“It also suggests that species diversity of birds in East Asia may be underestimated.”
The study was published in the journal Molecular Phylogenetics and Evolution.
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Jiande Li et al. 2023. A new bunting species in South China revealed by an integrative taxonomic investigation of the Emberiza godlewskii complex (Aves, Emberidae). Molecular Phylogenetics and Evolution 180: 107697; doi: 10.1016/j.ympev.2022.107697
