Ornithodesmus

bird link / bird ligament

• ornitho- · Greek · bird
• -desmos · Greek · bond, ligament, link

The name combines the Greek words 'ornithos' (bird) and 'desmos' (bond or ligament), meaning roughly 'bird link' or 'bird ligament'. It was chosen by Seeley in 1887 because the fused sacral vertebrae he described resembled those seen in birds, suggesting an evolutionary link or structural connection to avian anatomy. The name reflects the 19th-century interest in identifying dinosaur–bird relationships.

Named by

Seeley

Year named

1887

Period

Early Cretaceous

Stage

Barremian

Found in

Wessex Formation, Isle of Wight, England, UK

Originally described from fused sacral vertebrae and long thought to be a small dinosaur or archosaur. For much of the 20th century the name 'Ornithodesmus' was incorrectly applied to a small dromaeosaurid dinosaur (now known as Nuthetes or reassigned material), and separately to a pterosaur now called Istiodactylus. The type specimen itself (the sacrum) is now considered a nomen dubium because it cannot be reliably assigned to any known taxon. It is not a pterosaur — that material was referred in error. The animal, if a dinosaur at all, was likely a small theropod or bird-line archosaur.