Parabuthis question.

[skinheaddave]

I know this is a long-shot, as most people don't seem to read this board -- but does anyone have a reliable scientific reference for the ability/lack thereof of some species of Parabuthis to project venom?

I see a lot of websites with the info that three species of Parabuthis can project venom. There was also mention of this in the 1990 Polis book, I believe, but I may be imagining this. I don't have a copy available, though, and I would like a peer-reviewed paper to back this info up with.

Cheers,
Dave

 

[Solar Dart]

This is a topic Mikko and I were discussing a few weeks ago. He'd know more about this that I, because he actually keeps some of these. I do remember he told me that a friend of his was "spat" at, but that apparently it is rare for this to occur.
The only book I have on scorpions ("Scorpions" Manny Rubio) states that P. transvaalicus is the member of its genus most likely to spit and spary. Unfortunantly there is no bibliography in this book.

 

[skinheaddave]

Good book, though.

So I guess I can chalk up one more bit of anecdotal evidence -- but this one is only second-hand, so that's not too bad. Anyhow, I'm getting two P.transvaalicus mid-week, so I won't take any chances.

Cheers,
Dave

 

[Mikko]

Hi Solar and Dave

I have also been looking for some info about the spitting ability at Parabuthus sp. but it seems like there´s not much more info of it than that they could spit. I remember reading at some universities (dont know how to spell) homepage that they were also interested and they asked if anyone had the possibility to tape this "spitting".
I talked to one guy here in Sweden about this and he thought that all scorpions should have this ability, because they have to inject the venom into to the victims. But why Parabuthus sp. can spitt with more power i do not know. Personally i dont think the other scorps could do this. One thing that could be in the genus Parabuthus might be that the fifth (closest to vesicule) "segment" is slightly enlarged, could it have something to do with it?
Another thing about animals abilities of spitting that is interesting is that why do allmost every animal with this ability come from Africa/Asia? All spitting scorps are from Africa and all snakes (spitting cobras) are from Africa/Asia. The only animal that does spit outside of these two continents (as far as i know) is some species of spider in the USA. How could it be like this? Doesnt the scorps/snakes on other parts of the world need this deffensive ability? Does the scorps/snakes in Africa/Asia have somekind of special "enemies" that this spitting bites on really bad, that just stinging is not enough?
I got the mailadress to a guy name Wolfgang Wuster in Germany that is supposed to be an expert at Asian Najas, its a long shot but i´ll try to ask him. I´ll post the answer here if i get one.
And the species of Parabuthus i keep is P. transvaalicus and P. mossambicensis. I have never even seen any signs of spitting but safetyglasses should allweys be worn when handling these animals.
And yes, one of mine friends was spitted on. I remember it was the P. leiosoma. But i´ll ask him again so i dont provide any false information.
/Mikko Seppänen

 

[skinheaddave]

Mikko,

WARNING: This email is full of speculation.


With regards to the fifth segment, you would think that someone would have cracked one open by now to take a look. Perhaps it is part of that "lost science" that gets done but never published.

As for being limited to Asia/Africa, I suspect it is a case of there not being convergent evolution outside of these areas. Perhaps one could parallel it to the rattlesnake. Most snakes shake their tail when agitated, but only some in North America have developed rattles. They have done so under the selective pressure of living around a bunch of ungulates who like to step on things (and once you're stepped on, the ability to kill in self-defence just doesn't seem to matter so much).

Africa also has ungulates, but no African snake has developed a rattle. Now, it may be that there aren't the same selective pressures or maybe that mutation has never arrisen and been selected.

The same might be true of spitting ability. It definitely would allow a scorpion to deal with larger enemies whose skin couldn't be penetrated or who might kill a scorpion by trampling without caring about the sting. So there may very well be selective pressures favouring the development of spitting both in Africa/Asia and elsewhere, but the pressures may be different elsewhere or else the spitting ability has just never come to be.

Of course this whole discussion brings up the question of what stages were precursers to the ability of a scorpion to spit? Perhaps the ability to inject lots of venom really quickly to get greater localized distribution in that single instant?

Cheers,
Dave

 

[zoobugs]

Parabuthus Q's

Hey Dave,
Go to Jan Ove Rein's site:http://www.ub.ntnu.no/scorpion-files/
He has one of the most comprehensive lists on scorps and some good info on Parabuthus. BTW, not all Paras spray their venom.
Best...
Jim

 

[Wade]

Dave-

I found at least one reference to Parabuthus venom spraying in Polis's book. Chapter 2, Anatomy and Morphology by John T. Hjelle, under the section on "venom glands":

"On a related though not strictly morphological topic, Newlands (1974a) described the venom-squirting ability of seven species of Parabuthus. All these species have telsons with large vesicles, and the venom emerges as a fine jet or spray that may reach distances of up to a meter when squirted at a low trajectory and at least 50 cm when squirted vertically. The spray does not appear to be aimed in any definite direction, but its direction is generally toward the front of the scorpion."

The paper cited is listed in the biography:

Newlands, G. 1974. The venom-squirting ability of Parabuthus scorpions (Arachnida: Buthidae). South African Journal of Medical Science 39(4): 175-78

Ahhh...it's nice working at a place where I have a great natural history library at my fingertips!

Wade

 

[skinheaddave]

Wade,

Thanks. This is exactly why I have to break down and buy that book. When I have it out from the university library, I reference it constantly.

Where do you work?

Cheers,
Dave

 

[Wade]

Dave-

I work at a nature center called Three Lakes here in Richmond, VA. I get to order a lot of cool books I wouldn't be able to afford otherwise. We also have Punzo's Solifugid book "The Biology of Camel Spiders" that costs a whopping $150 and Prete's "The Praying Mantids" a more resonable $75. We just ordered Shelly's monograph of the North American Scolopendra, I can't wait to see that! My personal library, on the other hand, consists mostly of paperbacks

Wade

Just for fun, here's a pic of my P. transvaalicus, taken by Art Evans:

 

[Henry Kane]

Whoa Wade!!!! Feed that thing, it's starving for cryin' out loud!!!
Seriously though, is she gravid, or just a "cork bark potato"? ;P

Atrax

 

[Wade]

"Cork bark potato" I'd say. It was huge when I purchased it. Like you, I assumed it was a gravid female, which is part of why I wanted it! After several years nothing ever happened.

Wade