The Order Gobiesociformes contains just one single family of fish (Gobiesocidae) which contain up to 150 species of small clingfish.
Clingfish are just as the name suggests. They cling on to objects such as sea urchins, sea squirts, kelp, rocks and other fish. They are small, mostly less than 7cm in length, usually much smaller. They have dorsal fins that have evolved into suckers to enable them to cling to objects. Some are known to be able to change their colour to match their surroundings for added camouflage.