Ruvettus pretiosus, commonly known as the oilfish, is a deep-sea species found in tropical and temperate oceans worldwide. Notable for its elongated, dark body, this predatory fish thrives at depths of 100 to 800 meters. It is known for its unique ability to store wax esters, which can cause digestive issues in humans when consumed.

Ruvettus pretiosus, commonly known as the oilfish, is found in tropical and subtropical oceans worldwide. Its geographical distribution includes the Atlantic, Indian, and Pacific Oceans. It is commonly found near continental slopes and oceanic islands.

Ruvettus pretiosus typically inhabits deep-sea environments, ranging from 100 to 800 meters in depth. The species prefers temperate to warm oceanic waters and is often associated with mesopelagic zones characterized by low light and relatively stable temperatures.

As a deep-sea fish, Ruvettus pretiosus is adapted to life in the midwater column, where it preys on smaller fish and invertebrates. It plays a role in the oceanic food web as both predator and prey, and its biological adaptations include a robust, elongated body suited for swimming in open waters.