# Venom in Colubrid Snakes



## Willythegame (Sep 20, 2008)

been reading a few article on the potency of venon found in colubrid snakes,that we all keep. Here is but one ,fairly basic but definently shows the point. Nearly ALL snakes are venemous.

Toxin Molecular Evolution


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## Willythegame (Sep 20, 2008)

gonna have a look for some more articles........


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## stuartdouglas (Mar 5, 2008)

You should be aware of the difference between "venomous" and "possessing toxic saliva" Most colubrids possess toxic saliva, our own native grass snake included, but that doesn't make them venomous. For any reptile to be venomous it must have a means of producing and storing venom; venom glands in viperidae and elapidae, Duvernoy's glands in rear fanged colubrids (Boiga, Dispholidus etc), and a means of delivering venom, hollow fangs or enlarged grooved teeth.

So, sorry to p*ss on your bonfire, but not all snakes are venomous


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## Willythegame (Sep 20, 2008)

hey man "read the article" it clearly shows the possesion of "highly evolved" venom glands ,(believe it was the cat eyed snake).
Venom took from these glands posesses very many toxic substance not unlike cobra or viper VENOM.

As i said they posess venom,the delivery apparatus,is not so highly evolved but the rest apears to be.

and i said nearly all snakes are..not all...........


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## DASSIE (Jul 8, 2006)

interesting . another intersting fact is the common or rhombic night adder has venom glands that are suposedly the biggest in relation to snake size in the world, just the venom isnt considered deadly . It would be a truly fearsome snake should its venom be stronger as their vield is sooo masive .


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## rakpeterson (Oct 10, 2007)

The only snake i can see that it actually states has venom glands is the telescopus dhara , but this is already known to posses mild venom and is rear fanged, and the psammophis mossambicus which is also already known to posses venom glands. It goes on to say the venom which was previously thought to be weak is actually quite strong and very simillar to other venomous snakes considered dangerous. The way it describes other colubrids and the fact it doesnt state they have venom glands etc leads me to believe they are talking about the toxicity of saliva which they have noted may contain compounds that are more toxic than previously thought. It talks about the variable factors of some of these previously thought to be not dangerous and if anyone knows about these variable factors and the potential that some rear fanged snakes have its stuart (and a certain mangrove:whistling2

I dont think its right to say that most are venomous but i can see the issue that they illustrate.


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## Willythegame (Sep 20, 2008)

thanks for your thoughts 
quotes from the article

"Some non-venomous snakes have been previously thought to have only mild 'toxic saliva' but these results shown that they actually possess true venoms"

but as i said it states most snakes have venom glands, the sizes all range,i.e small in most rat snakes,massive in the cat eye.

"This research also shows that some of the snakes common in the overseas pet market actually produce highly potent venoms. However, this does not mean that all of them are going to be dangerous."

i think this makes sense,evolution wise.
most snakes get on the venom making path,some diversify before evolving the fang,venom gland is no longer particularly useful,is still there


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## stuartdouglas (Mar 5, 2008)

Willythegame said:


> hey man "read the article" it clearly shows the possesion of "highly evolved" venom glands ,(believe it was the cat eyed snake).
> Venom took from these glands posesses very many toxic substance not unlike cobra or viper VENOM.
> 
> As i said they posess venom,the delivery apparatus,is not so highly evolved but the rest apears to be.
> ...


Hey back, read my post, "Cat eyed snakes" aka Boiga sp. possess a Duvernoy's gland which is a primitive venom gland and they are widely recognised as rear fanged venomous snakes. Their venom is an extremely potent "three finger" neurotoxin, which, if they were able to deliver it efficiently and in sufficient quantities, would rank them as very dangerous. Why do you think the Gold ringed cat eyed snake (Boiga dendrophila) was on the DWA list for thirty one years?

this is probably why......

















I say again, other than these colubrids, (which far from constitute "nearly all" colubrid snakes) that possess Duvernoys glands, other colubrids merely have toxic saliva, and therefore cannot be classed as venomous


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## Willythegame (Sep 20, 2008)

what constitutes as a toxic saliva?
not a come on a forum where i cant actually see a guy and rant kinda person,just thought it was interesting and merited a discussion.


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## stuartdouglas (Mar 5, 2008)

Basically any product of salivary glands that aren't recognised as a means of storing and delivering venom. N n helvetica possesses toxic saliva, hell, they've even found supposedly venom gland in bloody beardies! It's whether the gland is linked by ducts to developed teeth to deliver venom, which, when all's said and done is purely modified saliva. In the cases of Ratsnakes etc, there is no direct link from the salivary glands to any enlarged/hollow teeth. IMO that's what forms the definition of venomous.
No one's having a rant, just healthy discussion: victory:


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## Willythegame (Sep 20, 2008)

that was my point mate,what ive said from the start, find it quite cool how this demonstrates how animals take different evolutionary paths.
I take on board that these snakes do not have the business end to deliver,but alot of snakes have got the underlying mechanics there, seen another article on this gonna dig it out,referred to venom in african colubrids........


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## ratboy (Jan 10, 2007)

Radiated rat snakes have been shown to have toxic saliva... it was one of the main snakes that the research was carried out on. They do not however have any fangs, either front or rear, so they have no means of injecting the venom into prey and cannot therefore really be regarded as venomous as they do not use it as venom in the same way that venomous snakes do.

When these snakes bite however, and I can vouch for this from experience, they do put their heart and soul into it. They latch on to whatever their target is and really give it a good chew before letting go. Whether this is an attempt to get some saliva into the preys blood stream or not, I don't know. But I do know some people that have had reactions to it with some mild swelling. I have had probably a hundred or so bites from my pair however and I have never reacted to it at all.

One interesting point about this species though is the attacking of multiple prey items. If they are offered multiple food items they will often attack and constrict one item and bite it at the neck with the same chewing motion as when they bite a hand. This item is then rolled down the body without letting it go and the next item is attcked, constricted and chewed. Both food items are then eaten.

Now in the wild and with live prey I would not expect this behaviour until the snake was sure that the first prey item was dead or at least nearly dead. As the food is rolled down the body and held mainly by the much weaker anterior body, the snake must be expecting the prey to not be putting up much of a struggle. 

So does the constriction alone kill the first prey item, or does the chewing of the preys neck put some of the snakes toxic saliva into the blood stream to help with the process ?


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## tidwellc (Feb 24, 2013)

Willythegame said:


> been reading a few article on the potency of venon found in colubrid snakes,that we all keep. Here is but one ,fairly basic but definently shows the point. Nearly ALL snakes are venemous.
> 
> Toxin Molecular Evolution


Officially, out of 2,400 species of snakes in the world, only 600 are considered "venomous," which could hardly be considered "most." Although as other posters stated, venom and "toxic saliva" are two very different things. Venom is something actually produced by a gland for that purpose. Heck, being bit by a human is regarded as being potentially dangerous due to infection from our saliva. Does this make humans "venomous?"


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