Entelognathus is a placoderm fish from the Ludlow-Early Devonian of China. It was named in 2013 by Min Zhu. It was the earliest known animal with a face, and due to having modern jaw anatomy, it has suggested that the common ancestor of jawed vertebrates was not some ancient cartilaginous fish, but rather, a placoderm.
Physiology[]
Entelognathus was a unique placoderm. It had the regular placoderm build (a modern-looking fish with an armored head, toothless jaws, and upward-facing tail); however, it also had very modern cranial and jaw bones, similar to non-placoderm bony fish and tetrapods. Its body would have been covered in scaly skin, with bony plates protecting its head.
Diet[]
Entelognathus was a predator, preying on small invertebrates. Its rough, toothless jaws were used for getting a hold of any struggling prey, as well as grinding them.
Ecology[]
Not much is known about Entelognathus.