Sihtturundus

Sihtturundus is a lesser-known, extinct genus of prehistoric bird that lived during the Late Cretaceous period, approximately 70 million years ago. Fossil remains of Sihtturundus have been discovered in what is now Mongolia, primarily in the Djadochta Formation, a renowned site for theropod dinosaurs and other Mesozoic fauna. The genus is represented by a single species, Sihtturundus ultimus, which was first described in 2007 by paleontologists.

Sihtturundus is notable for its small size, with estimates suggesting it measured around 30 centimeters (12 inches) in length, making it one of the smallest known enantiornithine birds. Enantiornithines were a diverse group of avian-like reptiles that dominated the skies during the Mesozoic era before being outcompeted and ultimately replaced by modern birds. Sihtturundus exhibits several anatomical features typical of enantiornithines, such as a long, tooth-bearing lower jaw and a unique shoulder structure adapted for flight.

The fossilized remains of Sihtturundus include partial skeletons, including fragments of the skull, limbs, and vertebrae. These specimens provide insights into its paleobiology, suggesting it was likely a ground-dwelling or semi-arboreal bird with adaptations for agile movement. The discovery of Sihtturundus contributes to the understanding of avian evolution during the Late Cretaceous, particularly the ecological diversity of enantiornithines in Central Asia.

Sihtturundus is often compared to other contemporaneous enantiornithines, such as Elanornis and Longipteryx, which also inhabited the same region. While these birds shared ecological niches, Sihtturundus may have occupied a distinct role in its ecosystem, possibly as a small predator or omnivore. Its extinction, along with that of other enantiornithines, marked the end of an era, paving the way for the rise of modern birds following the Cretaceous-Paleogene extinction event.