Euteleostomi

Skeleton of a bat.

Euteleostomi is the largest group of Vertebrates. Except for Hagfish, Lampreys, and cartilaginous fishes all vetebrates are part of this group. All Euteleostomi have a skeleton made of bone, and a skull. In the case of several fish related to the Sturgeon, most of the skeleton has again been transformed to cartilage.