Humpback Anglerfish

Melanocetus johnsonii

(mel-on-o-see-tus john-so-nee-eye)

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These fish may look like something out of a nightmare, but their large mouth and long teeth are perfect for catching a meal in the deep sea.

Humpback anglerfish live so deep in the ocean that no sunlight can reach them—so they’ve got their own source of light, known as an esca or illicium. This organ extends from their forehead and lures passing prey, drawing them in close enough for the anglerfish to devour. The light comes from bacteria that glow, a phenomenon known as bioluminescence. Only females have an esca, though, and they also use it to attract a mate.

The females of this species are approximately five times larger than the males and are also more dominant. Females can reach up to 6 inches (15.5 cm) long, whereas males only grow to 1 inch (3 cm)—a case of extreme sexual dimorphism!

Where They Live

The humpback anglerfish lives in the Indian, Atlantic, and Pacific Oceans. However, you won’t be able to meet one of these fish in person, as they live deep down in the ocean—up to 6,890 feet (2,100 m) deep!—in cold, dark regions called the mesopelagic and bathypelagic zones.

What They Eat

Because of their esca, or lure, these fish don’t need to be speedy swimmers, which explains why their bodies are so round. Instead, they drift slowly through the water, waiting for prey to come to them. They eat animals such as other fish, jellyfish, and krill, and can use their sharp, angled teeth and large mouths to capture and eat prey twice their size.

Conservation Status

Least Concern

Despite living so far away from people, humpback anglerfish still face threats caused by humans. They can be accidentally caught in trawlers, and the health of their deep-sea home can be negatively affected by climate change.

Fun Facts

• These anglerfish are also called humpback blackdevils.
• Only 8 male specimens have ever been found, in contrast to 852 females!
• In other anglerfish, the male latches on to the female’s body after mating and becomes parasitic, sharing her blood supply. Luckily, this isn’t the case for this species.
• These fish have very tiny eyes in proportion to their bodies—since they live in total darkness, they don’t need to see that well!
• The males have only one purpose in life: search for a mate, latch on, fertilize the egg, then take off to find another female.