Claudio Contreras / Finespotted Jawfish (Opistognathus punctatus), Bahia Magdalena, Baja California Peninsula, Mexico, June

Tony Wu / Jawfish (Opistognathus sp) looking around after spitting out sand and rubble to maintain burrow. Lembeh Strait, Celebes Sea, North Sulawesi, Indonesia.

Tony Wu / Jawfish (Opistognathus sp.) spitting out sand and stones to maintain its burrow. Lembeh Strait, Celebes Sea, North Sulawesi, Indonesia.

Tony Wu / Jawfish (Opistognathus sp.) spitting out sand and stones to maintain its burrow. Lembeh Strait, Celebes Sea, North Sulawesi, Indonesia.

Alex Mustard / Yellowhead jawfish (Opistognathus aurifrons) male churning / aerating eggs by spitting them out of his mouth. East End, Grand Cayman, Cayman Islands, British West Indies. Caribbean Sea.

Alex Mustard / Variable jawfish (Opistognathus variabilis) emerging from its hole in the sea bed, close to a coral reef. Ambon Bay, Ambon, Maluku Archipelago, Indonesia. Banda Sea, tropical west Pacific Ocean.

Alex Mustard / Yellowhead jawfish (Opistognathus aurifrons) male aerating his eggs by spitting them out of his mouth, a behaviour known as churning. These are new eggs and have not yet developed eyes. East End, Gran...

Alex Mustard / Yellowhead jawfish (Opistognathus aurifrons) spitting out sand as it digs its burrow. East End, Grand Cayman, Cayman Islands, British West Indies. Caribbean Sea.

Linda Pitkin / Gold-specs jawfish (Opistognathus randalli) Lembeh Strait, North Sulawesi, Indonesia.

Linda Pitkin / Gold-specs jawfish (Opistognathus randalli) Lembeh Strait, North Sulawesi, Indonesia.

Alex Mustard / Portrait of Yellow-headed jawfish (Opistognathus aurifrons) hovering in mid water above his burrow. East End, Grand Cayman, Cayman Islands, British West Indies. Caribbean Sea.

Alex Mustard / Male Yellow-headed jawfish (Opistognathus aurifrons) blows out the clutch of eggs he is incubating in his mouth to oxygenate them. East End, Grand Cayman, Cayman Islands, British West Indies. Caribbea...