So are centipedes venomous or poisonous?

[kevinlowl]

Fast forward to 4:25 to hear what the Attenborough has to say about that.

 

[chanda]

Poison (noun): a substance that through its chemical action usually kills, injures, or impairs an organism

Poisonous (adjective): causing sickness or death by entering or touching the body: containing poison; capable of putting poison into another animal's body by biting it.

Venom (noun): a toxic substance produced by some animals (such as snakes, scorpions, or bees) that is injected into prey or an enemy chiefly by biting or stinging and has an injurious or lethal effect; a substance that is poisonous

Venomous (adjective): producing venom in a specialized gland and capable of inflicting injury or death; full of venom

Toxin (noun): a poisonous substance that is a specific product of the metabolic activities of a living organism and is usually very unstable, notably toxic when introduced into the tissues, and typically capable of inducing antibody formation

Merriam-Webster

I know there's this whole poison vs. venom debate based on the method of delivery - poisons are injested or absorbed while venoms are injected - but really, venoms are a subset of poisons/toxins. The use of "poisonous" to describe a spider, snake, or other venomous animal is commonplace and - despite the pendantic folks who insist that this is unacceptable usage - readily understood. The two words are not synonymous and cannot be used interchangably, but there is some overlap. To describe something like a mushroom as "venomous" would be wrong, but describing a snake, spider, or centipede as poisonous is acceptable.

Besides, if you really want to get confusing, what about the blue-ringed octopus? The blue-ringed octopus is generally considered venomous because it delivers the venom through a bite - but the toxic compounds are in their saliva which they can "spray" into the water surrounding their prey, which then absorb it and are paralyzed by it.

 

[LawnShrimp]

Venomous- toxin injected through stingers, fangs, or other appendages, primarily used to kill prey
Poisionous- toxin contained in flesh, skin, or ejected from the body, primarily used as a defense.

All centipedes are venomous as all species have forcipules used to inject venom into prey. Most centipedes used as pets are not venomous but a good portion of the order Geophilomorpha have defensive glands along their sternites. Some species of Scolopendromorpha also have chemical defenses, such as Cormocephalus niditus which can eject a chemical spray, and the genus Asanada, which is rumored to use cyanide (like Polydesmid millipedes) as a defense.

All centipedes are venomous. Some species are capable of making non-venom poisons, but I wouldn't really call centipedes poisonous.

 

[Dennis Nedry]

Well he has been doing this for over 60 years and he doesn't read off a script, so you'd think he'd make a few tiny mistakes like this one

 

[LawnShrimp]

To be fair, he said "poisonous sting" which is pretty much correct; a sting generally injects a type of poison, which is venom.

He never said that centipedes are poisonous to consume or to touch.

 

[kevinlowl]

To be fair, he said "poisonous sting" which is pretty much correct; a sting generally injects a type of poison, which is venom.

He never said that centipedes are poisonous to consume or to touch.

This makes sense.

But can a centipede's fangs be called a sting? Are tarantula's fangs also a sting?

 

[LawnShrimp]

This makes sense.

But can a centipede's fangs be called a sting? Are tarantula's fangs also a sting?

Actually, yes. Fangs are teeth or mouthparts (for spiders, chelicerae) that have been modified to inject venom. Spiders have fangs and not stings. A sting is any other part of the anatomy that also does so, so a centipede bite is technically a sting as the forcipules are not mouthparts but modified legs. Still, the forcipules are close to the mouthparts and are used like fangs, so most people, including me, say bite instead of sting.

 

[Dennis Nedry]

This makes sense.

But can a centipede's fangs be called a sting? Are tarantula's fangs also a sting?

Think of how a cone snail's venomous barb is considered a sting even though it's on the snail's face rather than the lower body like on a wasp or scorpion. Anything that isn't part of the mouth is a sting technically speaking

 

[RTTB]

So a Spitting Cobra is both poisonous and venomous?

 

[Dennis Nedry]

I guess you could say that, there are other snakes considered poisonous and venomous at the same time

 

[chanda]

One thing that confuses me is the difference between injected digestive enzymes and venom. Assassin bugs (and some other predatory hemiptera) are not considered venomous - but they inject digestive enzymes when they bite. These enzymes - in addition to breaking down tissues for feeding - also kill, paralyze, or otherwise incapacitate their prey and cause intense pain when the bite is used defensively against a larger animal or person. So why are they not considered cytotoxic venoms?

 

[Dennis Nedry]

One thing that confuses me is the difference between injected digestive enzymes and venom. Assassin bugs (and some other predatory hemiptera) are not considered venomous - but they inject digestive enzymes when they bite. These enzymes - in addition to breaking down tissues for feeding - also kill, paralyze, or otherwise incapacitate their prey and cause intense pain when the bite is used defensively against a larger animal or person. So why are they not considered cytotoxic venoms?

That's odd, the enzymes are toxic so you'd think they'd be called venomous, right?