Anglerfishes are fish of the teleost order Lophiiformes /ˌlɒfiːəˈfɔːrmiːz/. They are bony fish named for their characteristic mode of predation, in which a fleshy growth from the fish’s head (the esca or illicium) acts as a lure.
Some anglerfish are also notable for extreme sexual dimorphism and sexual parasitism of the small male on the much larger female, seen in the suborder Ceratioidei. In these species, males may be several orders of magnitude smaller than females.
Anglerfish occur worldwide. Some are pelagic, while others are benthic; some live in the deep sea (e.g., Ceratiidae), while others on the continental shelf (e.g., the frogfishes Antennariidae and the monkfish/goosefish Lophiidae). Pelagic forms are most laterally compressed, whereas the benthic forms are often extremely dorsoventrally compressed (depressed), often with large upward-pointing mouths.