How Big Are Anglerfish? Deep-Sea Sizes vs Movie Monsters

Anglerfish sizes at a glance

“Anglerfish” covers more than 300 species in the order Lophiiformes. They range from deep-sea seadevils smaller than a matchbox to big monkfish caught for food. Here are some typical maximum sizes:

Sizes are maximum recorded lengths; most individuals are smaller. The deep-sea species are measured from preserved specimens, since very few have ever been seen alive.

How big is a typical deep-sea anglerfish?

The best-known deep-sea species, the humpback anglerfish, is a good example. The largest known females are about 18 cm (7 in) long, but most specimens are much smaller, and small ones weigh less than 10 g (0.35 oz). A large female would fit comfortably in your hand.

Many of the roughly 170 deep-sea anglerfish species are even smaller, with adult females only a few centimeters long. Their bodies are soft and loose, with thin bones and watery muscles, which keeps them light and close to the density of seawater. That helps them hover without wasting energy, an important advantage in a place where food is scarce.

The largest deep-sea anglerfish

The giant of the deep-sea group is Krøyer’s deep-sea angler (Ceratias holboelli), a warty seadevil found in all the oceans. Females are commonly about 77 cm (2.5 ft) in total length, and the largest published size is about 1.2 m (4 ft). Some footballfishes are also big for deep-sea fish: females of the Atlantic footballfish reach about 60 cm (2 ft).

These larger species are still rarely seen. Like other deep-sea anglerfish, they have been found in the stomachs of sperm whales, which hunt at great depths, and are occasionally caught in deep-water research nets.

Tiny males: the biggest size gap in fish

The most surprising size difference in anglerfish is between the sexes. In deep-sea species, males are dwarfs. A free-living male Krøyer’s deep-sea angler is only about 1.3 cm (0.5 in) long, while a large female can be more than 60 times longer and, by one estimate, around half a million times heavier.

In some families, the male bites onto the female and fuses with her for life. Once attached, he can grow much larger, up to about 16 cm (6 in) in Krøyer’s deep-sea angler, but he never lives independently again. The smallest of all are the attached males of Photocorynus spiniceps, at 6.2–7.3 mm (about 0.25 in), which are among the smallest sexually mature vertebrates ever recorded. Read the full story in how do anglerfish mate?, and see other record-breakers in our list of the smallest animals in the world.

Monkfish: the real giant anglerfish

If you want a big anglerfish, look on the seafloor rather than in the deep open ocean. Monkfish and goosefish (family Lophiidae) are flattened, bottom-living anglerfish with enormous heads and mouths. They lie camouflaged on sand or mud, from shallow coastal water down to about 1,000 m (3,300 ft), and wave a fleshy lure to attract fish.

The European angler (Lophius piscatorius) of the northeast Atlantic, the Mediterranean and the Black Sea is the largest anglerfish of all, reaching about 2 m (6.6 ft) and a record weight of 57.7 kg (127 lb). Most are much smaller, commonly around 40–100 cm (16–40 in). Its North American cousin, the goosefish or American angler (Lophius americanus), grows to about 1.2 m (4 ft) and 22.6 kg (50 lb). These fish are sold as “monkfish” in restaurants on both sides of the Atlantic.

Why do anglerfish look so big in pictures?

Many people picture anglerfish as monsters the size of a car, partly thanks to films such as Pixar’s Finding Nemo (2003), in which a huge glowing anglerfish chases the heroes through the dark. Real deep-sea anglerfish are nothing like that size.

Photographs add to the illusion. Most images are close-ups taken against a black background, with nothing to show scale. The wide, gaping mouth and long, needle-like teeth fill the frame, and the fish’s habit of swallowing prey as big as itself makes it seem larger and fiercer than it is. Preserved museum specimens often look bloated or distorted, too. To see how these fish use their glowing lures, read why do anglerfish have a light?, or explore more strange creatures in our list of deep-sea animals.