Researchers just discovered the first known venomous crustacean—a tiny centipede look-alike that lives in several underwater caves around the world, the BBC reports. The species, Speleonectes tulumensis, belongs to a group of animals called the remipedes. The discovery proves that venom did indeed evolve in all four of the main arthropod groups, the researchers write, and provides clues about the origin of venom evolution.
Nature describes these creepy creatures:
Observing these pale, blind and tiny animals in their natural habitat has been hard because they live in labyrinthine cave networks that are as difficult for divers to navigate as they are dangerous. Nonetheless, biologists including Björn von Reumont and Ronald Jenner, both of the Natural History Museum in London, found remipedes tossing away empty exoskeletons of shrimp, presumably having fed on them.
Upon closer inspection of these tiny-but-formidable specimens, the researchers noticed that the creatures possessed needle-like front claws. The hollow claws led to a venom gland, which produces a neurotoxin similar to that of some spiders. The remipede “breaks down body tissues with its venom and then sucks out a liquid meal from its prey’s exoskeleton,” the BBC says. (That’s one way to eat.) It remains unknown if the remipede venom would have any effect on a curious diver poking at the tiny creature; if we ever come across one, though, we’re going to hope not to be the ones to find out.
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