Reptile & Amphibian Forums

The message below referring to stiletto snakes as "long-gladed" reminded me of a question I've been meaning to ask.

This may be a bit vague since it's been a while. I saw a program on one of the animal/science channel abou some researchers looking for new species of snakes and they came across a thin snake that looked more or less like a garter snake to me (they didn't show a close up). They said it was something like a "asian coral snake" or an "oriental coral snake". At the time I looked for it on the internet and found something by that name, but it didn't look anything like what they found...

More importantly they said that it's venom glands ran 2/3 the length of it's body (and yes, I'm sure they said body), which sounded rediculous to me. I haven't found any reference to a snake with glands like that. Are they nuts? Am I missing something? Did they read somewhere that it's gland run 2/3 the lenght of its HEAD and misunderstand?
-----
Larry D. Fishel
Side effects may include paralysis
and death but are generally mild.

P.S. Please excuse all my typos. I hit "post" in stead of "preview" by askident.
-----
Larry D. Fishel
Side effects may include paralysis
and death but are generally mild.

My husband and I were discussing Asian corals just today. They do have VERY long glands but we couldn't remember if it was 1/3 or 2/3 of the body length. I can't remember where I saw/read that either. Maybe someone else can give us more info. The glands in the long glanded stiletto snakes only run 15% of the body length.

I was thinking about those long glanded corals today. The glands ARE supposed to run 2/3 of their body length. Why, I don't know! The glands of the long glanded stilettos only run 15% of the body length.

Sorry about that, I got an error message twice, so I didn't think it posted... I give up for tonight!

I'm quite sure I've also seen this information about venom glands two thirds as long as the body, but I can't remember where. I just took a quick look through some of the articles and books I have that seemed likely to contain any information and didn't find much.

The species I think I've read this about is the two Maticora sp.; M. bivirgata ssp. (Blue long-glanded coral snake), and M. intestinalis (Brown long-glanded coral snake).

I did find some information about long glands in Elazar Kochva's paper "The origin of snakes and evolution of the venom apparatus" published in Toxicon 1987, but that was about two Atractapis sp. Referring to two other articles he says that A. engaddensis may have glands reaching 8-12 cm (length of snake 50-60cm) and that 90 cm long A. microlepidota may have 30 cm long glands, ie the glands may be one third of the body length in this species.

If they can be one third of the body length (which seems somewhat excessively large to me! =)) perhaps it's not totally implausible there are species with even larger glands.

/Sundberg

According to Mehrtens in Living Snakes of the World, the glands of the malayan Long-Glanded Coral Snake "extend into the body a full third of its length. The heart is displaced posteriorly to allow accomodation of the glands. The purpose of such greatly elongated venom glands, however, is not known."

~~Greg~~

Does he mention the scientific name? Malayan long-glanded coral snake, that ought to be Maticora bivirgata flaviceps as far as I can figure out... In 'A photographic guide to snakes and other reptiles of peninsular Malaysia, Singapore and Thailand' by Cox et al they mention two common names for this subspecies; Blue long-glanded coral snake, and Blue Malaysian coral snake. Common names and all their varieties are just plain confusing sometimes! Thanks for the info though. Interesting stuff.

/Sundberg

Yes, it is the Malayan, M. bivirgata flaviceps that he was referring to.

~~Greg~~

I'm no sure which is more surprising, that a snake would evolve glands that long or that I had never heard of them before...

Has anyone seen any data on venom yield for these hyper-long-glanded snakes??
-----
Larry D. Fishel
Side effects may include paralysis
and death but are generally mild.

Has anyone seen any data on venom yield for these hyper-long-glanded snakes??
-----

Yes, I actually have an old paper about that; "Venom yields from three species of side-biting snakes (genus Atractaspis, Colubridae)" by WR Branch, published in Toxicon 1981.

He tests the yields of Atractaspis bibroni, A. dahomeyensis & A. engaddensis. He also mentions that the yields of A. microlepidota as reported by other authors is similar to that of A. engaddensis. There is no mention at all about the size of the venom glands in this article, but the amount of venom for the first two species are very much smaller than from the latter two. In light of what I found in Kochva's article (as I mentioned in an earlier post) about the very long glands in these two species I think it plausible that the glands of the first two species isn't as long.

Data from the article (the yield is wet weight);
A. bibroni, 5 specimens milked, length of specimens btw 337 and 430 mm, average venom yield 4,2 mg.
A. dahomeyensis, 3 specimens milked, one 412 mm long, one 525 mm long, one of unknown length, average venom yield 4,1 mg.
A. engaddensis, 1 specimen milked, length 641 mm, average venom yield 27,5 mg.

One thing I found interesting was the fact that he couldn't get significant amounts of venom from the snakes by massaging it out while they were anaesthetized, instead voluntary bites very necessary for venom ejection. Now I don't have any experience of milking snakes, but isn't it usually possible to massage the glands to get them to eject venom? Is it perhaps possible that this doesn't work for these snakes because the glands are so long that you only create pressure on a very small portion of the gland? Even if the data to me suggests that the glands from the first two species are smaller than for A. engaddensis or A. microlepidota perhaps they might still be longer than usual, or perhaps they are as long but thinner, thus presenting the same problem. Any input from someone with knowledge/experience of this would be very welcome!

/Sundberg

Hi mate

The long gland on an Atractaspis are very unusual structures. When we dissected them out of A. microlepidotus, they were not shaped like the regular gland but rather are flat, fettucini-like add ons. Very odd. This explains why the venom yield is not proportionately increased.

Cheers
BGF