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The link is below. This was the first cobra-style neurotoxin to be isolated from a 'non-venomous' snake. The mode of action and potency is comparable to similarly structured elapid neurotoxins.

Cheers
Bryan
alpha-colubritoxin paper

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Dr. Bryan Grieg Fry
Deputy Director
Australian Venom Research Unit
University of Melbourne

www.venomdoc.com

Hello Dr. Fry,

What I get from this paper is that:
A) The Colubritoxins are similar to Cobratoxins in structure and action, with the Colubritoxin being somewhat larger. Both fall within the 3FTX classification.

B) 3FTX was present very early on in the evolutionary process of Colubroid snakes, actually before the Viperine-Colubrid/Elapid split (therefore the absence in Viperine venoms). After the split of the Colubrids and Elapids, the Elapid venoms and delivery method evolved to it's present status (venom glands and proteroglyphic delivery), Colubrids (aglyphic) failed to evolve more advanced delivery methods and true venom glands (thus producing much smaller quantities), other Colubrids (opistoglyphic) developed slightly more advanced delivery systems with larger quantities of Colubritoxins and larger, more active Duvernoy's glands.

C) Colubritoxins are potentially present in just about any Colubrid snake at some level, but are not present in Boids. The quantities that are present in aglyphic Colubrids does not present a danger to humans. Naturally, this would vary case-to-case depending on the sensitivity of the individual to the Colubritoxin, allergies, anaphylaxis, etc.

D) This relationship is similar to the well known relationship of the different spiders. All spiders are venomous to one degree or another, some are dangerous to humans, some aren't and are considered harmless. Red-legged Tarantulas are commonly kept as pets, they can and do bite, they are venomous but there have been no recorded human deaths. A Sydney Funnel Web Spider, on the other hand is highly venomous to humans and requires extreme caution to maintain in captivity.

No one has ever died to my knowledge from a Corn Snake bite, but the Colubritoxins may very well be present. The thing that worries a lot of people in the snake keeping hobby/industry about these findings is the possibility of restrictive legislation being introduced by some well-meaning but misinformed legislator because of "safety" issues. It's tough to keep things in perspective when you see bylines like "Are there really ANY non-venomous snakes?" or "Deadly toxins isolated from snake previously considered "harmless." The fact is that the snake is still just as harmless to humans as it was before the toxins were found. Another potential problem I see lies with the people that are afraid of all snakes, make no distinction between venomous snakes and non-venomous snakes and simply kill all of them on sight. Now they have scientific data to back their philosophy.

The tendency of the press is to latch on to the parts of the findings that lend themselves to sensationalism (that's what sells papers). Headlines like "All snakes found to be venomous by Australian Venom Researcher!" could have enormous deleterious effects on the public image of snakes and people who keep them.

I understand the significance of the findings and I agree that it has far-reaching potential for the study of the evolution of snakes and venom, as well as significant importance in Biomedical research. I think it was a very well conducted study and the findings are conclusive and concise. You fellows did a remarkable job with this. I have heard people talking about this possibilty for years, but this is the first real research I've seen.

I believe that this research has real potential for helping to unlock some of the mysteries of the evolution of these animals, and to possibly project where that evolution is going in the future. It will help us gain more understanding of the animals we keep and study. However, I feel it may be somewhat of a double-edged sword, too.

Your thoughts?

Cheers,
G. Germany (oldherper)

It is not the message, it is (unfortunately) how it is perceived and applied. Pity, because in itself it is a good piece of research.

Frank
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"The luxury of not getting involved departed with the last lifeboat Skipper..."

I agree, it is very good research and resulted in very valuable data.

>>I agree, it is very good research and resulted in very valuable data.

Fangs for that guys. Yes, by and large it is a similar situation with the 'colubrids' as it is with the spiders. All spiders are venomous but only some have taken it to the lethal level. The same logic applies to the 'colubrids'. The vast majority will be only able to cause minor effects. This is typically due not to lesser relative toxicity (many are just as toxic as comparable elapids) but rather much smaller quantities of venom (with exceptions such as Psammophis and Telescopus) and much less efficient delivery (yet again with a few exceptions). A key element however to keep in mind is that non of the available antivenoms are likely to have any effect which does of course complicate the situation somewhat.

In regards to legislation, it will be a matter of education of the powers that be if there are any problems. I would be quite happy of course to lend my support and answer any questions (as I have done repeatedly in the past in favour of legalised keeping of elapids/vipers). I think it would be grossly inappropriate for the 'colubrids' to be typically placed on the same level as atractaspidids/elapids/vipers. Some proven lethal or genera proven capable of producing signficant envenomation should of course (including but not limited to Dispholidus, Malpolon, Philodryas, Psammophis, Rhabdophis, Thelotornis). The massive venom glands and quite potent venom of Telescopus makes this genus worth being considered as properly venomous. Their gentle temperment and small fangs does make envenomation much less likely but the capacity is certainly there. With new genera that become available, some sensible caution should be taken until they are evaluated a bit more (e.g. the very large and scary fangs of Macropisthodon certainly flags this genus as one to keep an eye on). Some keepers are already aware of certain genera that might also pose problems (e.g. Thrasops jacksonii is almost always treated with very high respect by the keepers due to their very quick and bloody mouse kill times).

All the best
Bryan
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Dr. Bryan Grieg Fry
Deputy Director
Australian Venom Research Unit
University of Melbourne

www.venomdoc.com

Interesting about Thrasops j. I have two (a green and a black).
Guess I'm in luck as both are quite polite when handled (and I love the licorice scent).

Frank
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"The luxury of not getting involved departed with the last lifeboat Skipper..."

I'm hoping to get my hands on a couple this year to have a good look at them to find out whats in there. We had obtained a couple but the airline froze them while going through Alaska (we were crushed).

I've heard a couple people comment about their scent, cool I have another project in the works where we are IDing what it is in the cloacal secretions that causes some snakes to be so pungent.

Take care mate
B

PS where is that quote on your signature file from? Are you a Titanic tragic or something? lol ;-p

Just ex Navy. I knew a chief PO that used to use that one back in the early seventies.

(EXCUSE ME WHILE I GO BACK TO SNIFF MY SNAKES............)(LOL)

FRANK
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"The luxury of not getting involved departed with the last lifeboat Skipper..."

The vast majority will be only able to cause minor effects. This is typically due not to lesser relative toxicity (many are just as toxic as comparable elapids) but rather much smaller quantities of venom (with exceptions such as Psammophis and Telescopus) and much less efficient delivery (yet again with a few exceptions). A key element however to keep in mind is that non of the available antivenoms are likely to have any effect which does of course complicate the situation somewhat.

I suppose one of the problems is that typically there is no effort or funds expended to develop antivenoms for a particular species if there has never been a reported case of serious envenomation in a human patient. For some of the Colubrid species you listed, I can also see that there would be a potential for a serious envenomation to occur, however small that potential may be. This would be especially true for more obscure species that are not commonly held in captive collections, and even more so should they suddenly become more available.

What puzzles me is that I have never heard of anyone being even mildly affected by the vast majority of colubrids commonly kept in captivity. I know that literally thousands of people are bitten every week by pet Rat Snakes and such, yet I have never heard of even one person being even mildly affected. I have been bitten many, many times by Colubrids over the past 35 years or so and have never had even so much as a rash or any swelling associated with the bite, save for some unusually heavy bleeding from Nerodia and Drymarchon bites. I even received a very nasty bite from a Boiga dendrophilia (he lacerated my finger pretty well with those back teeth) and the effects were very mild, some joint pain and very minor swelling and redness at the site of the bite. I'm not speaking of bites from Crotalid snakes or other known and accepted as dangerously venomous snakes. It goes without saying that those are quite unpleasant. I'm speaking strictly of bites from what are commonly considered to be harmless snakes.

So, with the knowledge that there have been literally millions of people bitten in the past by these Colubrids and none have been reported to have been affected by whatever amount of Colubitoxin is present in a Rat Snake, for instance, what does this data mean? I'm asking what it means in a practical sense to people that keep common Colubrids, putting aside for a moment what it means to medical and biological research. You mention that none of the presently available antivenoms would likely have any titer against Colubritoxin. Obviously there are some Colubrids that would require a close look at that, but I'm not referring to those rear-fanged potentially dangerous Colubrids. Does that mean that if there's no developed delivery system, such as is developed in the opistoglyphic species, that there is probably no danger? Some naturally are going to have smaller teeth and smaller mouths making delivery more difficult, just as some Elapids have very short fangs and small mouths. However, those Elapids are capable in certain circumstances of delivering fatal quantities of venom, and have done so in the past. Let's take a Corn Snake, for instance. According to the data, there would be a possibility of that species possessing small quantities of a potent toxin. However, he is an aglyphic species. Does that mean that in all of the thousands and thousands of Corn Snake bites, the snake was just unable to deliver enough toxin to cause harm or that he doesn't possess enough toxin to cause harm in a human? You would think that if enough toxin was present to cause harm, at least one out of a couple of hundred thousand would have done so. What about Radiated Rat Snakes? Has there ever been (to your knowledge) a case of serious efffects from a bite to a human?

Please understand that I'm in no way questioning the validity of the findings, I'm simply trying to put it into perspective from a practical standpoint.

Hi mate

There have been envenomations reported from 'non-venomous snakes' e.g. a documented case of neurotoxicity resulting from a garter snake bite after prolonged contact. However, other cases may exist that were dismissed as anxiety or allergy. Another , during the course of these studies I consulted on a neurotoxic envenomation from a Coluber rhodorhachis that caused notable moderate level neurotoxicity. In many cases for the widely kept species, even with prolonged contact the changes of significant envenomation are trivial. C. radiatus for example, we were averaging a milligram of crude venom per 2 meter adult. Obviously not nearly enough to cause obvious let alone clinical level envenomations. However, more than enough to help settle down a frog and therefore be useful in prey capture (which is the original and primary purpose of venom in snakes).

Cheers
Bryan
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Dr. Bryan Grieg Fry
Deputy Director
Australian Venom Research Unit
University of Melbourne

www.venomdoc.com

Thanks, Bryan! That does help put things in perspective.

>>What puzzles me is that I have never heard of anyone being even mildly affected by the vast majority of colubrids commonly kept in captivity. I know that literally thousands of people are bitten every week by pet Rat Snakes and such, yet I have never heard of even one person being even mildly affected.
>>
>>So, with the knowledge that there have been literally millions of people bitten in the past by these Colubrids and none have been reported to have been affected by whatever amount of Colubitoxin is present in a Rat Snake, for instance, what does this data mean? I'm asking what it means in a practical sense to people that keep common Colubrids.
>>
>Does that mean that if there's no developed delivery system, such as is developed in the opistoglyphic species, that there is probably no danger? Some naturally are going to have smaller teeth and smaller mouths making delivery more difficult, just as some Elapids have very short fangs and small mouths. However, those Elapids are capable in certain circumstances of delivering fatal quantities of venom, and have done so in the past. Let's take a Corn Snake, for instance. According to the data, there would be a possibility of that species possessing small quantities of a potent toxin. However, he is an aglyphic species. Does that mean that in all of the thousands and thousands of Corn Snake bites, the snake was just unable to deliver enough toxin to cause harm or that he doesn't possess enough toxin to cause harm in a human? You would think that if enough toxin was present to cause harm, at least one out of a couple of hundred thousand would have done so. What about Radiated Rat Snakes? Has there ever been (to your knowledge) a case of serious efffects from a bite to a human?
>>

Bryan, please clear this up for me:

From what I previously understood is it that "contact" with venomous snakes

(handling, and cleaning out cages, or in some instances getting bitten)
can make you somewhat sensitive to venom, which can lead to anaphalactic shock if you indeed get bitten bij a serious venomous one...

From what's present in your paper I understand that there is a possibility that someone who is repaetedly bitten by "harmless" snakes could build an allergy and whan that individual is bitten by,lets say, a cobra anaphalactic shock can occur...

any thoughys?

Keep up the good work

Cheers
Peter
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"No one likes us, we don't care"

There seems to be a little misunderstanding in this thread so I think I can shed some light on it. it is my understanding that the American genus; Pantherophis (Elaphe), Pituophis, Lampropeltis and relatives were listed (in the paper)as some of the few snakes not having the gland, which separates them from the European and Asian species that share similar common names (with American ratsnakes)and were formerly listed with them under the same genus. This is one of those discussions where the use of common names can get you into a real state of confusion.
American Corn snakes/Rat snakes cannot envenomate anyone.

Frank
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"The luxury of not getting involved departed with the last lifeboat Skipper..."

Well, see...that's kinda what I thought I understood, too. But from what Bryan is saying now, ALL colubrids fall into the venomous category (or at least have some level of Duvernoy's Gland activity). Not just European and Asian Rat Snakes, etc. but all colubrids.

It gets confusing...But I got this from Fry himself so it's as good a source as you can get on this. Just seems this one group of snakes lacks the goods. This does make a strong arguement for Latin (rather than common) names.

Frank
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"The luxury of not getting involved departed with the last lifeboat Skipper..."

Certainly does.

HI mate

There is some evidence that the common ancestor of the American group may have undergone a secondary loss of the venom (sort of how two lineages of sea snakes are independently becoming non-venomous as they are now specialising on fish eggs, so even with highly developed venomous snakes like elapids, evolution is still tinkering).

We'll be hitting the American lineage hard this year and will have an article on it by the end of the year, sorting it out one way or the other.

Cheers
Bryan
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Dr. Bryan Grieg Fry
Deputy Director
Australian Venom Research Unit
University of Melbourne

www.venomdoc.com

>>There seems to be a little misunderstanding in this thread so I think I can shed some light on it. it is my understanding that the American genus; Pantherophis (Elaphe), Pituophis, Lampropeltis and relatives were listed (in the paper)as some of the few snakes not having the gland, which separates them from the European and Asian species that share similar common names (with American ratsnakes)and were formerly listed with them under the same genus. This is one of those discussions where the use of common names can get you into a real state of confusion.
>>American Corn snakes/Rat snakes cannot envenomate anyone.
>>
>>Frank

Well, as far as beeing bitten by colubrids which I mentioned I was also referring to asian colubrids

I also understood from the paper that the american species weren't "toxic"
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"No one likes us, we don't care"

Which is exactly my point snakeskin. You said;

"Let's take a Corn Snake, for instance. According to the data, there would be a possibility of that species possessing small quantities of a potent toxin. However, he is an aglyphic species. Does that mean in all the thousands and thousands of Corn Snake bites, this snake was just unable to deliver enough toxinto cause harm in a human?"

I am not familiar with any Asian species refered to as a "Corn Snake", so If you could give me the Latin on it I would appreciate it. As most anyone would assume it was refering to the American Pantherophis guttata you may well understand the reason for the confusion, as well as my complaint about the usage of "Common names".

Frank
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"The luxury of not getting involved departed with the last lifeboat Skipper..."

Actually, Frank....I'm the one that said that, I think. But I was referring to the assumption that was being made (and not really corrected) that ALL colubrids possess this Colubritoxin.

The point that I was trying to make is that I didn't think that the study was saying that and that if that WAS what it was saying that very few actually possess the toxin in great enough quantities to be dangerous to humans. My point was that the Corn Snake that was not dangerous yeterday is STILL not dangerous today.

By the way, there is an Asian species that is commonly called a "Chinese Corn Snake". I do not know the taxonomy for this snake, but it is very similar to a North American Garter Snake. I see them on price lists from time to time.

LOL little misunderstanding here

I was quoting Oldherper on that

we were all indeed talking about P guttata yes, but it could as easily be a asian species to take as an example, for instance, and here's the big question :

I've been repeatedly bitten bij (excuse me for the old names)
elaphe taeniura species and Gonyosoma oxucephala.

So, would that make me more susseptible (did I spell that right? ) to elapid venom?

Cheers,
Peter
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"No one likes us, we don't care"

By that you would be referring to Elaphe rufodorsata. An Asian live bearing species that still eludes logic for being placed in that genus. Didn't know it by that name. We call them Chinese Garters here (again the common name thing).

I think you did start the corn thing but well...snakeskin raised the question that got my attention.

Frank
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"The luxury of not getting involved departed with the last lifeboat Skipper..."

Hi mate

I'm not so sure this is so clearcut anymore, Wolfgang came across a reference to a Lampropeltis bite that produced symptoms. We'll be having a close look at the American clade this year to sort it out.

Cheers
Bryan
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Dr. Bryan Grieg Fry
Deputy Director
Australian Venom Research Unit
University of Melbourne

www.venomdoc.com

A venomous Kingsnake? I sure you are going to point out Mate, that the real danger here is the species Legalophis overlegislatus. Your research (no matter how valuable) and the publicity that you attach to it has allready begun to do harm to the herpetologial community; by causing confusion and doubt about species that are totaly harmless. This can only resort to a "witch hunt mentality" in the private (non snake keeping but voting) sector who are quite capable of voting possesion of snakes out of our hands.
I know you see it from the viewpoint of a pure scientist, but the rest of us have to live with the impact. I don't favor suppressing knowledge, but then I don't think headlines like NOTED AUSTRALIAN SCIENTIST PROVES ALL SNAKES ARE VENOMOUS are of help to anybody except those who would shut us down. People are not going to make out the difference between Venomous and dangerous. If you doubt me, look at just today's posts on this forum.

Frank
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"The luxury of not getting involved departed with the last lifeboat Skipper..."

>>A venomous Kingsnake? I sure you are going to point out Mate, that the real danger here is the species Legalophis overlegislatus.

Yep, this is very true about the potential for overlegislation. That however is a separate arena from the scientific discovery, and is one that is a process of education. I agree that the media headlines are far from helpful sometimes, which is why we always make an explicit point that not all of these snakes will be dangerous.

As I mentioned before, I am more than happy to help fight any assinine legislation that may be proposed.

Cheers
Bryan
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Dr. Bryan Grieg Fry
Deputy Director
Australian Venom Research Unit
University of Melbourne

www.venomdoc.com

My only concern here mate is that the voice of reason is all too often shouted down by the idiots. Your papers have made it critical for there to be a reassesment (and listing)of what species are actually dangerous; because without that definitive statement, all snakes will be viewed as potentially so by the uninformed that make laws.

It is not the knowledge, it's the application of that knowledge that's the concern. Just remember, Gunpowder was invented to make pretty fireworks. BOOM!!!

Frank
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"The luxury of not getting involved departed with the last lifeboat Skipper..."

>>My only concern here mate is that the voice of reason is all too often shouted down by the idiots. Your papers have made it critical for there to be a reassesment (and listing)of what species are actually dangerous; because without that definitive statement, all snakes will be viewed as potentially so by the uninformed that make laws.
>>

Thats exactly what we are aiming to do, to provide as much evidence as possible concerning as many animals as possible (obviously we can't realistically do all of them so we are trying to get as wide a sampling as possible).

>>It is not the knowledge, it's the application of that knowledge that's the concern. Just remember, Gunpowder was invented to make pretty fireworks. BOOM!!!
>>

If you can get it onto an evidence based approach, it should be a reasonable state of affairs that the different sides can live with. Particularly since no one will disagree that Rhabdophis are potentially lethal (having actually killed people) but that rat snakes have venom but are of absolutely no danger. Education is the solution.

Cheers
Bryan
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Dr. Bryan Grieg Fry
Deputy Director
Australian Venom Research Unit
University of Melbourne

www.venomdoc.com

Posted by: BGF at Sat Jan 10 17:17:22 2004 [ Report Abuse ] [ Email Message ]

"I'm not so sure this is so clearcut anymore, Wolfgang came across a reference to a Lampropeltis bite that produced symptoms. We'll be having a close look at the American clade this year to sort it out."

>>>BGF, you must be kidding!?! How can you come up with the conclusion that Lampropeltis might be venomous to man when bite reactions are anything but consistent, and the psychological effects of the few reported bite(s) cannot be separated from real physiological ones. Here's a one example: My exgirlfriend's neighbor was working in her garden an thought she was bitten by a venomous snake. Her symtoms from the alleged bite were similar to a elapidae bite(sweating,numbness of the tongue, etc. Later the alleged snake was identified by the lady who was bitten. The alleged snake turned out to be a large earthworm!! In my opinion, you are wasting time doing research on these known harmless snakes.

>>Posted by: BGF at Sat Jan 10 17:17:22 2004 [ Report Abuse ] [ Email Message ]
>>
>>"I'm not so sure this is so clearcut anymore, Wolfgang came across a reference to a Lampropeltis bite that produced symptoms. We'll be having a close look at the American clade this year to sort it out."
>>
>>>>>BGF, you must be kidding!?!

Well, we did find cobra-toxins in ratsnakes. Anything else after that is pretty much fair game (and we did find these toxins absolutely bloody everwhere.

>! In my opinion, you are wasting time doing research on these known harmless snakes.

Well then you obviously have no interest in snake evolution or molecular evolution.

Cheers
Bryan
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Dr. Bryan Grieg Fry
Deputy Director
Australian Venom Research Unit
University of Melbourne

www.venomdoc.com

Posted by: BGF at Sun Jan 11 05:37:13 2004

"Well, we did find cobra-toxins in ratsnakes. Anything else after that is pretty much fair game (and we did find these toxins absolutely bloody everwhere."

>>So what. Finding toxins in lampropeltis is not going to make them truly venomous(biological definition) to man. The only evidence you have that would implicate Lampropeltis as being truly venomous to man is one measly case that produced symtoms that were more consistent(in my opinion) with a bateria infection than a cobra-toxin. It's amazing how you ignore evidence(thousands of bites in the U.S. with zero effects) that Lampropeltis is harmless to man but will grasp on to one case of a Lampropeltis evenomation that WW manage to dig up so you can justify your research.

Posted by: BGF at Sun Jan 11 05:37:13 2004

"Well then you obviously have no interest in snake evolution or molecular evolution."

>>My comment had nothing to do with snake evolution, so let me rephrase it for you. It's my opinion that you are wasting your time trying to implicate a snake(Lampropeltis) as being truly venomous to man when it has been known for many years that these snake are completely harmless. Ok?

Get a grip, mate. We aren't justifying our research on the basis of the medical importance of colubrids, but on the intrinsic interest of what their toxins tell us about venom evolution.

Cheers,

WW

>>Posted by: BGF at Sun Jan 11 05:37:13 2004
>>
>>"Well, we did find cobra-toxins in ratsnakes. Anything else after that is pretty much fair game (and we did find these toxins absolutely bloody everwhere."
>>
>>>>So what. Finding toxins in lampropeltis is not going to make them truly venomous(biological definition) to man. The only evidence you have that would implicate Lampropeltis as being truly venomous to man is one measly case that produced symtoms that were more consistent(in my opinion) with a bateria infection than a cobra-toxin. It's amazing how you ignore evidence(thousands of bites in the U.S. with zero effects) that Lampropeltis is harmless to man but will grasp on to one case of a Lampropeltis evenomation that WW manage to dig up so you can justify your research.
>>
>>
>>Posted by: BGF at Sun Jan 11 05:37:13 2004
>>
>>"Well then you obviously have no interest in snake evolution or molecular evolution."
>>
>>>>My comment had nothing to do with snake evolution, so let me rephrase it for you. It's my opinion that you are wasting your time trying to implicate a snake(Lampropeltis) as being truly venomous to man when it has been known for many years that these snake are completely harmless. Ok?
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WW Home

Posted by: WW

"Get a grip, mate. We aren't justifying our research on the basis of the medical importance of colubrids, but on the intrinsic interest of what their toxins tell us about venom evolution."

>>WW, posted below is what was said on this thread between rearfang and BGF.

----------------------------------------------------------------
Rearfang posted-

"My only concern here mate is that the voice of reason is all too often shouted down by the idiots. Your papers have made it critical for there to be a reassesment (and listing)of what species are actually dangerous; because without that definitive statement, all snakes will be viewed as potentially so by the uninformed that make laws."
---------------------------------------------------------------
BGF replied and posted-

"Thats exactly what we are aiming to do, to provide as much evidence as possible concerning as many animals as possible (obviously we can't realistically do all of them so we are trying to get as wide a sampling as possible)."

---------------------------------------------------------

The above statmentments led me to believe that some of your research was based on medical importance of colubrids. Ok?

>>BGF replied and posted-
>>
>>"Thats exactly what we are aiming to do, to provide as much evidence as possible concerning as many animals as possible (obviously we can't realistically do all of them so we are trying to get as wide a sampling as possible)."
>>
>>---------------------------------------------------------
>>
>>The above statmentments led me to believe that some of your research was based on medical importance of colubrids. Ok?

Of course some of it is of medical importance since some colubrids (even those lacking pronounced fangs) have caused severe or even lethal envenomations. If the lethal species are mapped over the taxonomical tree, you will see that they do not cluster all together but rather are scattered liberally, with each family already having at least one documented species capable of severe envenomations. We have consistently stated that despite virtually all 'colubrids' being now venomous, this does not mean that all will be dangerous. If you read any of the other threads you would have seen statements by me such as ratsnakes being no more dangerous today than they were a week ago.

You seem to be reacting rather emotionally to the whole thing and have the wrong impression about our intentions (the asssinine posts by Hoser early on certainly didn't help, not only does he suffer from paranoia and confusion but he seems to also be a carrier).

Relax, we are not trying to ban snakes or set them up to be banned. We are scientists fascinated by snake evolution. That is all.

Cheers
Bryan
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Dr. Bryan Grieg Fry
Deputy Director
Australian Venom Research Unit
University of Melbourne

www.venomdoc.com

Motive can be a noble thing and I understand where you are coming from. But your stuck in the loop that began, when your research started to question established (facts)beliefs. No easy road out of it Mate. People like black and white facts and you've given them a gray area to fret over. Expect lots more of these kinds of questions.
Frank
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"The luxury of not getting involved departed with the last lifeboat Skipper..."

>>Motive can be a noble thing and I understand where you are coming from. But your stuck in the loop that began, when your research started to question established (facts)beliefs. No easy road out of it Mate. People like black and white facts and you've given them a gray area to fret over. Expect lots more of these kinds of questions.
>>Frank
>>-----
>>"The luxury of not getting involved departed with the last lifeboat Skipper..."

Hi mate,

I'm not naive and think that I live in an ivory tower dispensing information and thats the end of it. I am more than happy to answer questions on this area, no worries at all. However, on the flip side the fact that we made these discoveries does not mean that we should have to wear the legislative fall-out. Thats not our arena and if stupid local laws are passed then the people affected by them have noone to blame but themselves for not educating the legislators. This is no different than any other scenario.

Cheers
Bryan
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Dr. Bryan Grieg Fry
Deputy Director
Australian Venom Research Unit
University of Melbourne

www.venomdoc.com

Unfortunately...He who stirs up the hornet's nest is usually the first to get stung. Goes with the territory I'm afraid.
Look what I'm dealing with a few posts above.....Frank
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"The luxury of not getting involved departed with the last lifeboat Skipper..."

Here is the abstract amd reference to the Lampropeltis bite mentioned by BGF.

Note:
1. I have not seen the paper itself
2. I have therefore not been able to verify how and by whom the snakes were identified
3. I have no details on the timescale of symtoms after the Lampropeltis bite and whether infection or some other factor may have been involved. Oedema and lymphangitis are not consistent with psychological effects.
4. Even if everyhting is genuine as written, does that mean that Lampropeltis is dangerous? No, of course it doesn't - we all know how many people keep these and how there have been absolutely zero reports of other envenomed bites, and even this one does not appear to have been anything other than minimal.

Envenomation: A real risk of keeping exotic house pets
de Haro L, Pommier P
VETERINARY AND HUMAN TOXICOLOGY
45 (4): 214-216 AUG 2003

Abstract:
The fashion of exotic animals maintained as pets is increasing in France. Cases of envenomation after exotic animals bites or stings were studied. All 54 non-native animal envenomations reported by hospitals at the Poison Centre of Marseilles (3 south-eastern regions of France) between 1997 and 2002 were surveyed. They involved 22 snakes, 18 fishes, 11 spiders, 1 scorpion and 2 marine invertebrates. The snakes belonged to crotalids (genus Crotalus, Sistrurus, Agkistrodon and Trimeresurus), viperids (genus Bitis, Echis and Macrovipera, responsible for extensive swelling and coagulation disturbances), elapids (Naja and Dendroaspis which induce severe neurological signs), and colubrids (Lampropeltis with pain, edema and lymphangitis). Nine of the 22 patients bitten by snakes needed Intensive Care Unit management, and 5 of them received antivenom. Fish stings produced severe pain and local swelling. An Amazonian Stingray Potamotrygon histrix case had extensive swelling and malaise, headache and tremor. Pain and lymphangitis developed from tarantulas bites, and a black widow bite produced a severe diffuse muscle pain and contractions, and blood pressure disturbances. Exotic pets can be dangerous for their owners and family. Since antivenom from foreign countries is not often available in France, these cases raise the Question of society's responsibility for treatment costs.
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WW Home

Posted by: WW at Sun Jan 11 06:11:46 2004

"3. I have no details on the timescale of symtoms after the Lampropeltis bite and whether infection or some other factor may have been involved. Oedema and lymphangitis are not consistent with psychological effects"

>>>Oedema and lymphangitis may not be consistent with psychological effects, but they are consistent with pathogenic organisms(i.e. bacteria) that could have enter the wound.

>Oedema and lymphangitis may not be consistent with psychological effects, but they are consistent with pathogenic organisms(i.e. bacteria) that could have enter the wound.

Exactly. That is why we are going to have a close look at this clade in particularl to resolve if they still posses venom like the other 'colubrids' or if they are a case of a specialised loss of venom (as histological evidence implies).
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Dr. Bryan Grieg Fry
Deputy Director
Australian Venom Research Unit
University of Melbourne

www.venomdoc.com

HI mate

Developing an allergy after bites from 'colubrids' and then cross reacting with elapids is a possibility but a very very very remote one. You'd have a much higher chance of developing a nasty dust mite allergy.

Cheers
Bryan
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Dr. Bryan Grieg Fry
Deputy Director
Australian Venom Research Unit
University of Melbourne

www.venomdoc.com

Dr. Bryan Grieg Fry wrote:

“Fangs for that guys. Yes, by and large it is a similar situation with the 'colubrids' as it is with the spiders. All spiders are venomous but only some have taken it to the lethal level. The same logic applies to the 'colubrids'. The vast majority will be only able to cause minor effects. This is typically due not to lesser relative toxicity (many are just as toxic as comparable elapids) but rather much smaller quantities of venom (with exceptions such as Psammophis and Telescopus) and much less efficient delivery (yet again with a few exceptions).”

I am not an entomologist so I am in no position to evaluate Dr. Fry's claim that all spiders are venomous, and that they only differ in their toxicity of their venom. However, Dr. Fry's claim that all colubrids are venomous is extremely controversial and definitely unsupported by scientific evidence.

Dr. Kenneth Kardong, for example, disagrees strongly with this assertion. Dr. Kardong (2002) writes:

'One of the largest groups of snakes is the family Colubridae. This is a paraphyletic assemblage that includes a few venomous species, but most pose no special health risk to humans. Thirty to forty percent of colubrids possess a Duvernoy’s gland, a specialized oral gland located in the temporal region. Although it is a homologue to the venom glands of viperid and elapid snakes, the Duvernoy’s gland is anatomically and functionally distinct. Generally it lacks a large internal reservoir of secretion, emptying is under low-pressure flow, and the secretion is not delivered via hollow fangs. In contrast, true venom glands hold a large store of ready venom, expel the venom under direct action of striated muscles, and inject it as a high-pressure pulse via hollow fangs. Both the Duvernoy’s gland and the venom gland are part of a snake’s trophic system, involved primarily in predatory behavior. True venoms are composed of potent toxins whose main biological role is to bring about rapid prey death. Although the secretion from the Duvernoy’s gland may include toxins, surprisingly only a few colubrids deploy it similarly to kill prey quickly. In fact, the biological role(s) of Duvernoy’s secretion remain today largely unknown. Therefore, it is misleading, in a functional and evolutionary context, automatically to call Duvernoy’s secretion a venom (biological role) when only its pharmacology (property) is known. Although Duvernoy’s secretion has some components in common with true venoms, some may be fundamentally different in chemical composition, likely because it is involved in different biological roles than a true venom. This means it likely includes novel chemical components with a promise of interest to human medicine.'

It is clear that not all colubrids have Duvernoy's glands, that the Duvernoy's gland is not a true venom gland, and that the secretions from the Duvernoy's gland (even if they are dangerously toxic in some cases) are used by but a few colubrids to cause rapid prey death. Therefore it is a leap in logic to claim that all colubrids are venomous, like all spiders.

Dr. Kardong further emphasized his point with the following comment:

'The point is as obvious as this: human saliva is toxic[67] with clinical manifestations if injected subcutaneously.[68] But from this pharmacological property (toxic) or from these clinical symptoms (erythema, edema) we would not conclude that humans use their saliva as a venom! Toxicity is clearly an incidental byproduct of human saliva, not an indication of biological role. The biological role is determined by how the secretion contributes to an animal’s survival, which can be determined only by actual empirical study of its use in the wild.[69] Outside of the few colubrids that can rapidly kill prey and defend with oral secretions, the biological role(s) of Duvernoy’s secretion are today unknown and unverified.[70]'

If the biological role of the Duvernoy's secretion is unknown and unverified, the assertion that these secretions are venom because they are toxic constitutes a leap of faith. The claim that all colubrids are venomous is not a conclusion based on science; it is a conclusion that is based on an unverified assumption. As such, this claim is controversial and not widely accepted, despite the fact that it is being promoted vigorously in the popular press and in Internet discussion forums by those who support it.

Reference

Kardong, Kenneth 2002. COLUBRID SNAKES AND DUVERNOY’S ‘‘VENOM’’ GLANDS. Journal of Toxicology, TOXIN REVIEWS, Vol. 21 numbers 1&2, pages 1–19.

Fry et al. wrote in their abstract:

"Abstract. The evolution of venom in advanced snakes has been a focus of long-standing interest. Here we provide the first complete amino acid sequence of a colubrid toxin, which we have called alpha-colubritoxin, isolated from the Asian ratsnake Coelognathus radiatus (formerly known as Elaphe radiata), an archetypal nonvenomous snake as sold in pet stores. This potent postsynaptic neurotoxin displays readily reversible, competitive antagonism at the nicotinic receptor. The toxin is homologous with, and phylogenetically rooted within, the three-finger toxins, previously thought unique to elapids, suggesting that this toxin family was recruited into the chemical arsenal of advanced snakes early in their evolutionary history."

This is an interesting finding, but their finding does not necessarily support Fry et al.'s conclusion. Convergent evolution in molecules have been repeatedly reported in the literature. For example, puffer fishes and newts are both known to have biochemically similar toxins, suggesting perhaps that tetrodotoxin may have evolved early, in the common ancestor of newts and puffer fishes. But this is not the case at all as it has been shown that tetrodotoxin is of bacterial origin and independently acquired by newts and puffer fishes. Therefore before one leaps to the conclusion that alpha-colubritoxin or a similar molecule evolved early in the common ancestor of the colubrids and the elapids, further investigations are needed.

Below I call attention to another recently published paper that may be of interest to those pondering the origin of venom in colubroid snakes:

Kohji Okumura, Seiji Inoue, Kiyoshi Ikeda, and Kyozo Hayashi 2002. Identification of beta-type phospholipase A2 inhibitor in a nonvenomous snake, Elaphe quadrivirgata . Archives of Biochemistry and Biophysics 408 (2002) 124–130

Below is a quote from the abstract of this paper:

“A novel serum protein inhibiting specifically the enzymatic activity of the basic phospholipase A2 (PLA2) from the venom of the Chinese mamushi snake (Agkistrodon blomhoffii siniticus) was purified from a nonvenomous Colubridae snake, Elaphe quadrivirgata. The purified inhibitor was a 150-kDa glycoprotein having a trimeric structure, composed of two homologous 50-kDa subunits. Their amino acid sequences, containing leucine-rich repeats, were typical of the beta-type PLA2 inhibitor (PLIbeta), previously identified from the serum of A. blomhoffii siniticus. The inhibitor inhibited exclusively group II basic PLA2s and did not inhibit other kinds of PLA2s. This is the first paper reporting the existence of PLIbeta in a nonvenomous snake. The existence of PLIbeta in the nonvenomous snake reflects that PLIbetas are widely distributed over the snake species and participate commonly in regulating the physiological activities of the unidentified target PLA2s."

Okumura et al. further isolated PLA2 from the liver and lung of Elaphe quadrivirgata. Does finding PLA2 in E. quadrivirgata and Agkistrodon blomhoffii siniticus mean that PLA2 evolved in the common ancestor of these 2 species? This is certainly possible, although the possibility that E. quadrivirgata evolved PLIbeta as defense against the Japanese mamushi (A. halys blomhoffii),on which it occasionally preys, cannot be ruled out.

In short, relatively little is known of the biochemistry of snakes, and toxic substances have turned up in unexpected places. Just because these substances are toxic, however, does not mean that they evolved originally as venom nor does it mean that they evolved in the common ancestor of the snakes that possess them. It would be premature to call any toxin isolated from a snake "venom" or to label any snake which may have toxic compounds within its body a "venomous" snake.

Thanks for the paper