Scientists Capture the First Footage of an Anglerfish’s Parasitic Mating Ritual

The deep sea is full of alien-looking creatures, and the fanfin anglerfish is no exception. The toothy Caulophryne jordani, with its expandable stomach and glowing lure and fin rays, is notable not just for its weird looks, but also its odd mating method, which has been captured in the wild on video for the first time, as CNET and Science report.

If you saw a male anglerfish and a female anglerfish together, you would probably not recognize them as the same species. In fact, in the video below, you might not be able to find the male at all. The male anglerfish is lure-less and teeny-tiny (as much as 60 times smaller in length) compared to his lady love.

And he's kind of a deadbeat boyfriend. The male anglerfish attaches to the female's belly in a parasitic mating ritual that involves biting into her and latching on, fusing with her so that he can get his nutrients straight from her blood. He stays there for the rest of his fishy life, fertilizing her eggs and eventually becoming part of her body completely.

Observing an anglerfish in action, or really at all, is extremely difficult. There are only 14 dead specimens from this particular anglerfish species held at natural history museums throughout the world, and they are all female. Since anglerfish can't live in the lab, seeing them in their natural habitat is the only way to observe them. This video, shot in 2016 off the coast of Portugal by researchers with the Rebikoff-Niggeler Foundation, is only the third time we've been able to record deep-sea anglerfish behavior.

Take a look for yourself, and be grateful that your own relationship isn't quite so codependent.