This image shows the skull of the venomous species Meiacanthus grammistes
Credit: Anthony Romilio
The teeth are enormous relative to its body size so you see immediately why this organism engenders so much fear. Add a unique type of venom to the creature and you have all the makings of the next John Carpenter movie.
Fang blennies are small fish with big teeth. Specifically, they have two large canine teeth that jut out of their lower jaw. Since blenny fish are only about two inches long, these "fangs" would be less than intimidating if not for the venom within. Blenny fish venom most likely causes a sudden drop in blood pressure in would-be predators, such as grouper fish, that have been bitten by blennies, researchers report on March 30 in Current Biology.
Science Daily: This timid little fish escapes predators by injecting them with opioid-laced venom
Ed: it's only two-inches long. What kind of terror is that?
A really horrifying one if you're one-inch long, I imagine. Besides, sometimes they get to (gasp) ten centimeters (i.e. about four inches).
Here's what a Blenny really looks like:
Ed: wow. That really looks demonic
Truly
There is an actual reason for the interest in the Blenny beyond dredging up ideas for John Carpenter movies. There are two questions the researchers wanted to resolve. The first was what's in the venom they use and the second is how such a mechanism evolved in the first place.
When fangs evolve as in a snake, for example, it makes some sense since the animal needs some way to inject the venom so the magic of evolution makes that happen. In other words, their large view is venom existed already so the snake needed to evolve fangs to deliver it. The intrigue for them in the Blenny is it appears to have happened the other way around; the ability to produce venom came after they evolved the big teeth / fangs.
Another surprise from the study was the evidence suggesting that fang blenny fangs evolved before the venom. "This is pretty unusual, because often what we've found -- for example, in snakes -- is that some sort of venom secretions evolved first, before the elaborate venom delivery mechanism evolved," says Casewell. Evolution favored the tiny fish with large teeth first and later found a way to enhance them with venom.
- SD
Note: if you will use 'pretty' as an adjective to embellish anything which is not possessed of physical beauty, just don't ... ever. Got it?
Ed: pretty much
Arrrggghhhh
We could hang about and pander the magic of evolution all day long and I'm just positive you would like to participate in such an inspiring journey but we want to know what's in that venom.
When the researchers did a proteomic analysis of extracted fang blenny venom, they found three venom components -- a neuropeptide that occurs in cone snail venom, a lipase similar to one from scorpions, and an opioid peptide. And, surprisingly, when they injected the blenny venom into lab mice, the mice didn't show any signs of pain.
"For the fang blenny venom to be painless in mice was quite a surprise," says study co-author Bryan Fry of University of Queensland. "Fish with venomous dorsal spines produce immediate and blinding pain. The most pain I've ever been in other than the time I broke my back was from a stingray envenomation. 'Sting'ray sounds so benign. They don't sting. They are pure hell."
- SD
A venom which causes no pain seems useless particularly when a specific predator is the grouper which may outweigh the blenny by several hundred pounds. Surely it takes a really brutal venom to stop such a creature but that isn't how it works.
Fang blenny venom, however, seems to have a very different effect on its victims. Since the researchers used rodents for the pain test, they can't entirely rule out the possibility of blenny venom causing pain in fish, but it seems plausible that the neuropeptide and opioid components may cause a sudden drop in blood pressure, most likely leaving the blenny's attacker disorientated and unable to give chase. "By slowing down potential predators, the fang blennies have a chance to escape," says Fry. "While the feeling of pain is not produced, opioids can produce sensations of extremely unpleasant nausea and dizziness [in mammals]."
- SD
We know at least generally of the effect of opioids and, what do you know, it appears these tiny fish use such chemicals as a defense.
We're still not really buying the premise, however. For the tiny blenny to have any effect on a grouper which outweighs it by a factor of hundreds, it would have to inject a substantial amount of venom or carry the deadliest venom on the planet. Neither seems to be true so we're not really seeing how this works.
Ed: I just want to know if it's yet one more sea creature which can make me dead
There's no room for a detective forensics show since it's unlikely you can use them as part of a clever plot to kill an errant spouse.
A bite might hurt us, but shouldn’t cause anything other than mild, localised pain. In any case, the chances of venom being delivered with a bite are slim, due to the small size of the blenny’s mouth.
- Practical Fishkeeping: BEWARE THE BLENNY'S BITE!
Aren't you glad you asked.
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