Psychrolutidae is a family of fish commonly known as fatheads or blobfish. They are primarily found in deep-sea environments, particularly in the cold waters of the Southern Ocean and around Antarctica. These fish are characterized by their gelatinous bodies, which help them withstand high-pressure conditions at great depths. The most well-known member of this family is the blobfish (Psychrolutes marcidus), which gained fame for its unusual appearance when brought to the surface. Fatheads have a diet that includes small invertebrates and are adapted to their unique habitats, making them an interesting subject of study in marine biology.