Cynoglossidae

Western Pacific tonguefish

Symphurus thermophilus

Dark crossbands on brown side

• Tropical
• Island endemic
• Island endemic species
• Local endemic species
• Restricted distribution
• Marine fish
• Pacific Ocean
• East Asia
• Oceania
• Small
• Tropical fish

Symphurus thermophilus is a species of tonguefish notable for being the only flatfish known to be an obligate inhabitant of hydrothermal vents. It is known to inhabit several widely dispersed locations in the western Pacific Ocean and occurs in great numbers. These flatfish are distinguished by the prominent dark crossbands on their brown eyed side, black abdominal cavity membrane lining known as the peritoneum, and white blind side.