Kingdom Animalia
Phylum Chordata
Superclass Tetrapoda
Class Aves
Subclass Enantiornithes
Order Iberomesornithiformes
Family Iberomesornithidae
Genus Iberomesornis
1st Species Iberomesornis romerali
Other attributes
Time Range 130-125 mya
Location Spain
Name Meaning Iberian intermediate bird
Physical Dimensions 20 centimeter wingspan
Dietary Classification Carnivore

Iberomesornis is an iberomesornithid iberomesornithiform bird from the Early Cretaceous of Spain. It was named in 1992 by Jose Luis Sanz and Jose Bonaparte. It is considered to be one of the many avian intermediates that exist, being a transition from the primitive proto-birds of the Jurassic to the modern birds that can be seen flying through the skies today.


Iberomesornis looked a lot like modern birds; it had a small, sleek body, moderately long legs, a short, feathery tail, long wings, and a presumably long head. However, it also had a few major differences; for example, the fingers on its hands were not joined in a fleshy mitt and ended in claws, and its mouth was adorned with small teeth. Most of its body (excluding its snout and legs) would have been covered in long, vaned feathers.


Iberomesornis was a predator, feeding on insects and other small arthropods. Although what kind of teeth it had is still up to debate, it can be certain that it was used for grabbing onto insect prey.


Iberomesornis was an evolutionary step-up from early birds such as Archaeopteryx, as it had features that more resembled those of later birds. For example, it had a short tail that ended in a pygostyle (a set of vertebra combined into one single bone that supported the tail feathers), and its shoulders were aligned in a way so that its wings could raise themselves above horizontal position (allowing it to fly much more efficiently); along with this, its feet had prehensile toes along with an opposable hallux (first toe), which shows that it was one of the first birds to make a transition from climbing trees to perching on branches. In terms of how it lived, due to the lack of a known head, it is currently unknown what Iberomesornis ate and how it hunted; however, like any other Mesozoic bird at the time, it can be assumed that insects, perhaps the most viable small prey item at the time, served as prey for it. Due to the fact that its habitat was a lake surrounded by dense forests, it can be assumed that Iberomesornis probably lived near the lakeshore, snatching insects out of the air and near the water's surface.

In popular cultureEdit

Iberomesornis was featured in the 4th episode of the 1999 documentary Walking with Dinosaurs, where an entire flock attack an unsuspecting Tropeognathus in order to protect their eggs. As well as this, it is mentioned that birds like it have evolved from dinosaurs, with the narrator going on to explain that they lost their scaly skin in exchange for feathers (which was a prevalent idea at the time).

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