An international team of ornithologists has discovered a new species of drongo living in the forests of western Africa.
A square-tailed drongo in Mkhuze Game Reserve, South Africa. Image credit: Alan Manson / CC BY-SA 2.0.
Drongos are a family (Dicruridae) of Old World perching birds. All species in this family are placed in a single genus, Dicrurus.
These birds have black or dark-gray plumage, sometimes with a glossy metallic sheen and complex tail shapes that include long forks.
They feed like flycatchers or shrikes, taking large insects and termites. Their voices are loud mixtures of harsh and sweet sounds; some species, like the racket-tail, are good mimics.
Drongos can be found in a number of locations, including: Africa, Central Asia, Australia, Europe, western Pacific islands and Madagascar.
The newly-discovered species, named the western square-tailed drongo (Dicrurus occidentalis), is distributed across the gallery forests of coastal Guinea, extending to the Niger and Benue Rivers of Nigeria.
The bird was discovered by Sorbonne University researcher Jerome Fuchs and his colleagues from Guinée-Conakry, Denmark and the United States.
“This species inhabits secondary forest and gallery forest from coastal Guinea to Nigeria,” the scientists said.
“Based on rather scattered locality records, the eastern distribution limit appears to be bounded by the Niger/Benue River system in Nigeria.”
The western square-tailed drongo belongs in the square-tailed drongo (Dicrurus ludwigii) complex.
It differs from previously described species in this complex by possessing a significantly heavier bill and via substantial genetic divergence from its sister-species, the Sharpe’s drongo (Dicrurus sharpie).
“According to our divergence time estimates, the western square-tailed drongo and the Sharpe’s drongo diverged about 1.3 million years ago,” the ornithologists said.
“During this time, multiple climatic oscillations occurred, which could have led to isolation and divergence of populations followed by remixing of gene pools.”
Dr. Fuchs and co-authors were unable to record the western square-tailed drongo in the field, but they found one vocalization of the species on www.xeno-canto.org — a call from Dande, Senegal.
“We suspect that this species was overlooked by previous avian systematists because they either lacked comparative material from western Africa or because the key diagnostic morphological character (bill characteristics) was not measured,” they said.
The discovery is outlined in a paper in the June 20 issue of the journal Zootaxa.
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Jerome Fuchs et al. 2018. Taxonomic revision of the Square-tailed Drongo species complex (Passeriformes: Dicruridae) with description of a new species from western Africa. Zootaxa 4438 (1); doi: 10.11646/zootaxa.4438.1.4
