Anglerfish

The anglerfish are ray-finned fish in the order Lophiiformes. Both the order's common and scientific name come from the characteristic mode of predation, in which a modified dorsal fin ray acts as a lure for prey (akin to a human angler, and this lure is also likened to a crest or "lophos"). The modified fin ray, with the very tip being the esca and the length of the structure the illicium, is adapted to attract specific prey items depending on the species, through the employment of different luring methods. Anglerfish occur in marine waters worldwide, from tropical seas to polar regions, and live in both shallow water habitats and the deep sea. Many species are benthic or demersal, including monkfishes, batfishes, frogfishes, and sea toads; these groups use enlarged pectoral and/or pelvic fins to rest on or move across the seabed. In contrast, the deep-sea anglerfish lack pelvic fins and are pelagic, swimming and drifting in the water column. Anglerfish are notable for their sexual dimorphism, which is sometimes extremely pronounced; the females may be several orders of magnitude larger in mass than males. In the deep-sea anglerfish, this dimorphism has enabled a unique reproductive method, where the male attaches to the much larger female, sometimes fusing together as an example of natural parabiosis. This phenomenon is known as sexual parasitism. Anglerfish are of some commercial value, with many species being of interest to aquaria. The lophiid anglerfish (marketed as monkfish, goosefish, or simply angler) are fished commercially as their meat is highly valued, being considered a delicacy throughout the world.

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