Alex Mustard,Alex Mustard / A signal blenny (Emblemaria hypacanthus) displays its showy dorsal fin as it extends out of its tube home. La Paz, Mexico. Sea Of Cortez, East Pacific Ocean.

Alex Mustard / Sailfin blenny (Emblemaria pandionis) male displaying his large dorsal fin, East End, Grand Cayman, Cayman Islands, British West Indies, Caribbean Sea.

Norbert Wu / Sailfin Blenny (Emblemaria pandionis) male courting, West Palm Beach, Florida

Franco Banfi / Gulf signal blenny (Emblemaria hypacanthus) resting on seabed, close up, Baja California, Mexico, Sea of Cortez.

Alex Mustard / Sailfin blenny (Emblemaria pandionis) peering out from hole on a coral reef, close up, Grand Cayman, Cayman Islands, Caribbean Sea.

Alex Mustard / Male Sailfin blenny (Emblemaria pandionis) displaying large dorsal fin, portrait, Grand Cayman, Cayman Islands, Caribbean Sea.