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When imagining a venomous animal with fangs and unique defense mechanisms, a likely image to conjure would be that of a cobra or rattlesnake snake — not a fish.
The fang blennies, though unassuming, are crayon-sized, vibrantly-colored, adorable reef fish … for the most part, at least.
When they open their mouths to smile, two surprisingly large canine teeth appear, grinning and able to deliver a poisonous bite.
While the shrimpy two-inch underwater creature may not at first seem intimidating to other would-be sea bullies, its canines pack a venomous punch.
Potential predators won’t flee from this defense in agony, but pleasure, says a paper published in Current Biology on Thursday.
The poisonous injection acts as an opioid, drastically slowing a predator’s attack long enough so it can flee the scene.
“We have never seen a venom acting this way,” said lead author of the study Bryan Fry, of the University of Queensland. “It’s completely novel.”
“The fish injects other fish with opioid peptides that act like heroin or morphine, inhibiting pain rather than causing it,” said Fry. “What’s interesting is that these peptides are identical to our natural painkiller ones.”
However, the peptides are much smaller, which also made it less difficult for Fry and his team to produce a synthetic version that was capable of being absorbed by the body quickly.
“Fanged blennies are the most interesting fish I’ve ever studied and have one of the most intriguing venoms of them all,” Fry added.
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