A previously unrecognized species of the antthrush genus Chamaeza has been discovered in the isolated highland rainforests of northeastern Brazil.
The Baturité antthrush (Chamaeza baturitensis). Image credit: Fábio Nunes.
“Chamaeza comprises ground-dwelling suboscine birds specialized for life in the understory of Neotropical forests,” said Universidade Estadual Paulista ornithologist Vagner Cavarzere and his colleagues.
“These secretive birds occupy forest floors from lowland to mid-elevation montane habitats, where they forage primarily in leaf litter and among fallen logs for arthropods.”
“Although they occasionally follow army ant swarms, this behavior occurs less frequently than in other ant-following birds.”
“Chamaeza species exhibit cryptic plumage adapted for leaf-litter camouflage, with no apparent sexual dimorphism.”
“Their reproductive strategy involves nesting in natural cavities of decaying logs, with biparental care extending through the nestling and fledgling stages.”
“Ecologically, they are solitary foragers with limited dispersal capacity, reflecting their specialization for stable forest interiors.”
“The genus consists of six species with distinct biogeographic distributions across South America’s forested regions.”
In their new study, the authors found that populations of the short-tailed antthrush (Chamaeza campanisona) living in the Baturité Mountains of Brazil’s Ceará state are distinct enough to warrant classification as their own species: Chamaeza baturitensis (common name is the Baturité antthrush).
“Currently, 12 subspecies of Chamaeza campanisona are recognized, exhibiting a broad yet fragmented distribution across northern and central South America,” they explained.
The researchers analyzed 183 audio recordings of two Chamaeza campanisona subspecies (C. c. campanisona and C. c. tshororo) collected from across the Atlantic Forest region, combining traditional acoustic analysis with machine-learning tools.
The findings revealed three distinct song patterns among eastern South American populations.
Birds in the Baturité Mountains sing faster, longer songs than their relatives to the south, with no overlap in pace between the groups.
The researches analyzed 134 museum specimens of the two Chamaeza campanisona subspecies. In addition, they examined another 80 specimens through photographs.
