Agonus cataphractus, commonly known as the hooknose, pogge or armed bullhead, is a species of fish in the Agonidae family, close to the scorpion fish. It is the only species of the genus Agonus. It is characterized by being covered in hard, bony plates, which limit the flexibility of its body. It reaches up to 21 centimetres (8.3 in) in length, but is typically found at sizes of 10–15 centimetres (3.9–5.9 in). It features numerous barbells beneath a flattened head.