Sylviornis was a huge flightless bird, 1.7 m (5.6 ft) long altogether, and weighing around 30 kg (66 lb) on average.
It is the most massive galliform known to have ever existed.
It had a large skull with a high and laterally compressed beak surmounted by a bony knob.
Its legs were rather short, but had strong toes with long nails.
The skeleton has a number of peculiarities and differences that make Sylviornis stand apart from all other known birds: the clavicles were not fused to a furcula, the number of caudal vertebrae was very high, and the ribcage and pelvis were almost dinosaurian in appearance.
The wings were reduced to small stubs.
Sylviornis was a huge flightless bird, 1.7 m (5.6 ft) long altogether, and weighing around 30 kg (66 lb) on average. It is the most massive galliform known to have ever existed. It had a large skull with a high and laterally compressed beak surmounted by a bony knob. Its legs were rather short, but had strong toes with long nails. The skeleton has a number of peculiarities and differences that make Sylviornis stand apart from all other known birds: the clavicles were not fused to a furcula, the number of caudal vertebrae was very high, and the ribcage and pelvis were almost dinosaurian in appearance. The wings were reduced to small stubs.
Sylviornis