The well-preserved fossil of a previously unknown toothed bird that lived during the Cretaceous period, some 115 million years ago, has been found in the northeastern Brazilian state of Ceará.
Reconstruction of the fossil bird from the Cretaceous of the Crato Formation, Araripe Basin, Brazil. Image credit: Deverson Pepi, via novataxa.blogspot.com.
A team of paleontologists led by Dr Ismar de Souza Carvalho of the Federal University of Rio de Janeiro examined the skeleton, complete with feathers, unearthed from the Crato Formation, Araripe Basin, in 2011.
The fossil represents an as-yet-unnamed prehistoric genus and species, and belongs to Enantiornithes – a group of early birds with teeth and clawed wings that eventually all went extinct.
According to the team, the specimen was a juvenile with a head and body length of 2.4 inches (6 cm), with a 3 inch (7.6 cm) long tail, and had long, ‘ribbon-like’ tail feathers (unknown in living birds).
“One interesting thing of this small bird with the size of a hummingbird is the large feathers in the tail,” said team member Dr Fernando Novas of the Bernardino Rivadavia Natural Sciences Museum in Buenos Aires, Argentina.
Until now, birds with this tail design were known to have lived only in what is modern-day China.
The picture shows the main slab of the fossil. Scale bar – 1 cm. Image credit: Ismar de Souza Carvalho et al.
“There are possible traces of original colors, which were important to the relationships among the members of this species,” said Dr Novas, who is a co-author of a paper published in the journal Nature Communications.
“The skeleton is covered by filamentous feathers, including approximately ten preserved secondary remiges anchored on the forearm,” the paleontologists wrote in the paper.
“The base of the rachis (central shaft of the feather) bears a row of five granulate spots, which we interpret as remnants of an ornamental color pattern. The spots are distributed in a symmetrical paired line along both rectrices and shows comparable morphology, size, contour and color. On this basis, we hypothesize that these spots may reflect the color pattern of the feather and not a taphonomical artefact.”
The scientists said the specimen is the oldest bird fossil yet from Gondwana, the supercontinent that once encompassed South America, Antarctica, Africa, Australia and India.
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Ismar de Souza Carvalho et al. 2015. A Mesozoic bird from Gondwana preserving feathers. Nature Communications 6, article number: 7141; doi: 10.1038/ncomms8141
