Alexornis (name meaning “Alexander’s Bird”) is a genus of enantiornithine bird that originated during the Late Cretaceous period in what is now North America.
In the Series 2 episode "Super Croc II: River of Death," a flock of Alexornis, one of which being a male named Alex, were brought to the park from Late Cretaceous Alberta, 75 million years ago. They reside in the Aviary Enclosure.