These venomous, benthic fishes are found on sandy or silty substrates of lagoon and seaward reefs, in coastal regions of tropical oceans.

The ten described species are collectively known by various common names, including ghoul, goblinfish, sea goblin, spiny devilfish, stinger, and stingfish.

Inimicus was first described as a genus in 1904 by the American ichthyologists David Starr Jordan and Edwin Chapin Starks with the type species designated as Pelor japonicum,[1] which had been described by Georges Cuvier in 1829 from the seas of China and Japan.

The waters of the Red Sea off the coast of Egypt appear to mark the westernmost limit of their range, while specimens have been reported as far to the east as New Caledonia.

[20][21] Inimicus are benthic fishes, living mainly on the bottom of mangrove swamps and coral reefs, at depths between 5 and 450 meters.

The skin is without scales except along the lateral line, and is covered with venomous spines and wartlike glands which give it a knobby appearance.

They are nocturnal and typically lie partially buried on the sea floor or on a coral head during the day, covering themselves with sand and other debris to further camouflage themselves.

When they do move, they display an unusual mechanism of subcarangiform locomotion---they crawl slowly along the seabed, employing the four lower rays (two on each side) of their pectoral fins as legs.

This type of locomotion, based on voluntary and coordinated movements of paired pectoral fins, is believed by some to be a precursor to the later development of similar ambulation in terrestrial vertebrates.