Just how venomous are Sicarius?

GartenSpinnen

Arachnoprince
Old Timer
Joined
Aug 17, 2005
Messages
1,407
So i never even heard of this species until recently. The most i hear is "very very venomous". Well just "how" venomous? Are we talking widow venomous, or are we talking wandering spider/Sydney funny web venomous? Whats the deal on them? Are they new to the hobby or have they been around for a bit? Can they climb glass? I heard they are communal? If so thats pretty cool. Are they as fast as i hear, like P. murinus fast, or faster? I am thinking of custom building a secure enclosure for one. It would be thick acrylic with locking lid, etc. Any information is appreciated.
Cheers

(Oh yea, i found some information on the internet on them, but i would like to hear first hand from people that have actually been around them.)
 

froggyman

Arachnoangel
Old Timer
Joined
Nov 26, 2006
Messages
801
im not sure on how venomous but im pretty sure their venom has necrotic factors like recluses
 

EightLeggedFrea

Arachnoangel
Old Timer
Joined
Dec 18, 2007
Messages
818
I first learned about this spiders from Todd Gearhart (tarantulaspiders.com), and on his site he mentioned they are highly venomous, among THE most venomous spiders in the world. They can also live as long 15 years, making among the most long-lived true spiders.
 

Tarantula_Hawk

Arachnobaron
Old Timer
Joined
Nov 24, 2005
Messages
445
Well the nasty aspect of the sicarius (and the whole sicariidae family in general) is that they have necrotoxic venom, meaning that one bite, if not deadly, can really mess things up. As for now, the sicarius is viewed by most as the most venomous spider in the world, however not the most dangerous as encouters with humans are very rare (as it lives in the desert and tends to hide). As a consequence there is no antivenom available
Widow spiders and funnel webs have instead a neurotoxin venom, which can indeed be deadly. Fortunatley today both antivenoms are available, and there has been no casualties since the dicovery of this antivenom
Wandering spiders are also considered by others as the most venomous of all. They too have neurotoxic venom and an antivenom (which has prevented deaths since its introduction). In addition most of the bites from wandering spiders have been seen as being "dry" bites, that is no/very few venom is injected.
So basically the fact that there is no antivenom available, and very few is known about the venom itself, probably makes them the most dangerous spiders to keep (even if they do not have an active behavior).

Edit: Forgot to say i have no experience with them as i have never kept one. I wouldn't recommend any non-expert keeper to keep one, as i think safety comes first^^
 
Last edited:

Venom

Arachnoprince
Old Timer
Joined
Jul 21, 2002
Messages
1,700
So i never even heard of this species until recently. The most i hear is "very very venomous". Well just "how" venomous? Are we talking widow venomous, or are we talking wandering spider/Sydney funny web venomous? Whats the deal on them?
They are far, FAR beyond the widow / recluse spiders in toxicity, and probably more toxic than the funnelwebs ( Atrax and Hadronyche ) as well. These are absolutely at the top of arachnid toxins, and they can very easily kill a human, none of this "dangerous for children/ elderly" stuff.

As for the specifics, the genus Sicarius is in Sicariidae along with the recluse spiders, their close relatives. They therefore share the same toxic compound: Sphingomyelinase D, an enzyme which acts to dissolve tissues. In otherwords, it is a cytotoxic venom: it acts by "popping" all kinds of cells, bursting them like balloons. However, in the Sicarius venom, this toxin is far more concentrated than in recluse venom, which, coupled with the Sicarius' large size ( 3+ inches ), means this species injects both more venom, and a much more toxic venom than our native L. reclusa. This has a number of wide-ranging effects. First of all, like the recluse spiders, it causes a spreading wound of tissue death: a necrotic sore. Unlike the typical recluse bite, this very easily can become enormous, and cause the loss of a limb (a documented occurrence). Massive local tissue loss is expected to be typical, rather than the exception.

Secondly, the venom of Sicarius, like that of Loxosceles, bears the possibility of leaching out into the bloodstream, where it attacks red blood cells. ( only, again, on a more massive level than L.reclusa ). This first causes a loss of red blood cells to carry oxygen, but no problem, these can be replaced by the spleen and bone marrow. The problem comes in with what happens to the dead blood cells: they become so numerous, as more blood cells are "popped," then replaced, and the replacements "popped," that the bloodstream ends up carrying more skins of blood cells than the kidneys can filter or the liver can absorb. This sheer overload of dead cell membranes in the blood shuts down the kidneys.

However, the death of blood cells is not the only cardiovascular problem to occur. The arteries and veins are also composed of soft cells, and so are vulnerable to the venom, which attacks them also, wearing away the integrity of your blood vessels ( it's an equal-opportunity destroyer, rupturing every cell-based tissue it contacts ). This results in hemorrhages throughout the body, as blood vessels become weakened from the action of the venom, and begin rupturing here and there ( aneurysms ).

Clotting is also messed up, as the venom causes the blood, thickened with its own dead cells, to clot. This produces millions of tiny blood clots everywhere in the circulatory system, which lodge in vessels ( especially the narrow capillaries ), and cause occlusions, which cut off blood supply in random regions of the body, which results in more areas of necrotic tissue developing. This action of the venom can result in strokes, heart attacks, and other occlusion conditons, in addition to the aneurysm epidemic as weakened blood vessels lose integrity.


But wait, there's more. The venom also causes swelling of the liver, and heart damage, and leaves you open to massive infection of your gaping bite-area wound.

So there you have it: your kidneys shut down, the heart and liver are being damaged, heart attacks, strokes and aneurysms are going off all over. You have no blood flow to speak of, and tissue is dying right left and center, even far away from the bite site. You have the equivalent of accellerated leprosy, combined with Ebola. There is no antivenom. Have a nice day. {D


Are they new to the hobby or have they been around for a bit?
Yes, extremely new. They have not been in the US hobby until last fall I believe. Even so, they are very scarce, and only a handful are available at a time.

Can they climb glass?
Probably. Most true spiders can, and with the nearness of relation of Sicariidae to Sparassidae, I would expect the glass climbing ability to be present in Sicarius as well.

I heard they are communal? If so thats pretty cool.
Hmm, haven't heard anything about this. I really doubt it though.

Are they as fast as i hear, like P. murinus fast, or faster?
They are EXTREMELY quick, agile, and maneuverable. Just check out the videos on Youtube. Lightning quick, and strong feeding response.

I am thinking of custom building a secure enclosure for one. It would be thick acrylic with locking lid, etc.
That would be an appropriate caution. You don't want this escaping, or anyone tampering with it. As always, though, count the cost. These things are risky, and the cost for a mistake is your life. This isn't a widow, where an "oops" is pretty much survival guaranteed, unless you're a kid, elderly or ill. These have a VERY high chance of fatality, and even if you survive, you have the (VERY STRONG ) possibility of heart, liver, kidney, muscle, and brain damage. Don't think I am exaggerating, these are at least as toxic as Atrax robustus, and far worse than Phoneutria in overall effect. You won't walk away unscathed. Or, I'll put it this way. I know of two documented bite cases from a Sicarius sp. One was fatal, and the other man lost his arm. That's 50% established fatality, and 100% morbidity so far in documented cases. Not statistics to be fooling with or taking lightly.

So please, consider whether you are ready for this kind of animal. They really ought to be an experts-only species.
 

syndicate

Arachnoemperor
Old Timer
Joined
Aug 26, 2005
Messages
4,497
wow i didnt realize that there venom was that deadly.i sure hope none of these end up in the wrong hand especially with no anti-venom available.on a serious note tho all it will take is one person to die from a bite and that could easily have a huge impact on our hobby.i find these spiders very interesting but im kinda iffy about keeping any animals that can kill me hehe
 

What

Arachnoprince
Old Timer
Joined
Jul 13, 2006
Messages
1,150
Probably. Most true spiders can, and with the nearness of relation of Sicariidae to Sparassidae, I would expect the glass climbing ability to be present in Sicarius as well.
As far as I have been able to tell with my specimen they cannot climb glass/plastic. I am not saying that given the right conditions they wont(caulking in corners, dirt on surface, etc) but mine while scratching at the sides of its deli has not been able to climb up the sides.
 

Quixtar

Arachnobaron
Old Timer
Joined
Sep 22, 2007
Messages
513
As far as I have been able to tell with my specimen they cannot climb glass/plastic. I am not saying that given the right conditions they wont(caulking in corners, dirt on surface, etc) but mine while scratching at the sides of its deli has not been able to climb up the sides.
I can vouch for that. That just might be the saving grace for these little devils. My adult female can't climb glass, but is horrifyingly fast.
 

MaartenSFS

Arachnobaron
Old Timer
Joined
Apr 26, 2008
Messages
484
They are far, FAR beyond the widow / recluse spiders in toxicity, and probably more toxic than the funnelwebs ( Atrax and Hadronyche ) as well. These are absolutely at the top of arachnid toxins, and they can very easily kill a human, none of this "dangerous for children/ elderly" stuff.

As for the specifics, the genus Sicarius is in Sicariidae along with the recluse spiders, their close relatives. They therefore share the same toxic compound: Sphingomyelinase D, an enzyme which acts to dissolve tissues. In otherwords, it is a cytotoxic venom: it acts by "popping" all kinds of cells, bursting them like balloons. However, in the Sicarius venom, this toxin is far more concentrated than in recluse venom, which, coupled with the Sicarius' large size ( 3+ inches ), means this species injects both more venom, and a much more toxic venom than our native L. reclusa. This has a number of wide-ranging effects. First of all, like the recluse spiders, it causes a spreading wound of tissue death: a necrotic sore. Unlike the typical recluse bite, this very easily can become enormous, and cause the loss of a limb (a documented occurrence). Massive local tissue loss is expected to be typical, rather than the exception.

Secondly, the venom of Sicarius, like that of Loxosceles, bears the possibility of leaching out into the bloodstream, where it attacks red blood cells. ( only, again, on a more massive level than L.reclusa ). This first causes a loss of red blood cells to carry oxygen, but no problem, these can be replaced by the spleen and bone marrow. The problem comes in with what happens to the dead blood cells: they become so numerous, as more blood cells are "popped," then replaced, and the replacements "popped," that the bloodstream ends up carrying more skins of blood cells than the kidneys can filter or the liver can absorb. This sheer overload of dead cell membranes in the blood shuts down the kidneys.

However, the death of blood cells is not the only cardiovascular problem to occur. The arteries and veins are also composed of soft cells, and so are vulnerable to the venom, which attacks them also, wearing away the integrity of your blood vessels ( it's an equal-opportunity destroyer, rupturing every cell-based tissue it contacts ). This results in hemorrhages throughout the body, as blood vessels become weakened from the action of the venom, and begin rupturing here and there ( aneurysms ).

Clotting is also messed up, as the venom causes the blood, thickened with its own dead cells, to clot. This produces millions of tiny blood clots everywhere in the circulatory system, which lodge in vessels ( especially the narrow capillaries ), and cause occlusions, which cut off blood supply in random regions of the body, which results in more areas of necrotic tissue developing. This action of the venom can result in strokes, heart attacks, and other occlusion conditons, in addition to the aneurysm epidemic as weakened blood vessels lose integrity.


But wait, there's more. The venom also causes swelling of the liver, and heart damage, and leaves you open to massive infection of your gaping bite-area wound.

So there you have it: your kidneys shut down, the heart and liver are being damaged, heart attacks, strokes and aneurysms are going off all over. You have no blood flow to speak of, and tissue is dying right left and center, even far away from the bite site. You have the equivalent of accellerated leprosy, combined with Ebola. There is no antivenom. Have a nice day. {D




Yes, extremely new. They have not been in the US hobby until last fall I believe. Even so, they are very scarce, and only a handful are available at a time.



Probably. Most true spiders can, and with the nearness of relation of Sicariidae to Sparassidae, I would expect the glass climbing ability to be present in Sicarius as well.



Hmm, haven't heard anything about this. I really doubt it though.



They are EXTREMELY quick, agile, and maneuverable. Just check out the videos on Youtube. Lightning quick, and strong feeding response.



That would be an appropriate caution. You don't want this escaping, or anyone tampering with it. As always, though, count the cost. These things are risky, and the cost for a mistake is your life. This isn't a widow, where an "oops" is pretty much survival guaranteed, unless you're a kid, elderly or ill. These have a VERY high chance of fatality, and even if you survive, you have the (VERY STRONG ) possibility of heart, liver, kidney, muscle, and brain damage. Don't think I am exaggerating, these are at least as toxic as Atrax robustus, and far worse than Phoneutria in overall effect. You won't walk away unscathed. Or, I'll put it this way. I know of two documented bite cases from a Sicarius sp. One was fatal, and the other man lost his arm. That's 50% established fatality, and 100% morbidity so far in documented cases. Not statistics to be fooling with or taking lightly.

So please, consider whether you are ready for this kind of animal. They really ought to be an experts-only species.
Very informative post. :worship: I'm always interested by animals that keep humanity in check. We shouldn't be too arrogant. May I ask what your source is?
 

Moltar

ArachnoGod
Old Timer
Joined
Apr 11, 2007
Messages
5,438
Yikes. Holy snikeys.

Wow, that's a really nasty bite.

Why do the extremely dangerous ones have to have such fascinating behavior?
 

GartenSpinnen

Arachnoprince
Old Timer
Joined
Aug 17, 2005
Messages
1,407
I no longer will be getting one, too risky to have around a family, even when precautions are taken! I have noted that these are falling into the "wrong" hands... read some posts on here... i already have a feeling our hobby is headed down a one way street here of lately. Especially with the new fad of "bug fighting". Now theres gonna be teeny boppers all over trying to get ahold of A. australis and such to fight with there friends... probably this spider also when they discover how fast and proficient it is. It just takes 1 concerned parent and a lot of media attention to screw up a good thing... especially one that involves something 90% of the population has a phobia of.
Cheers
 

hauser

Arachnosquire
Old Timer
Joined
Feb 20, 2008
Messages
80
So i never even heard of this species until recently. The most i hear is "very very venomous". Well just "how" venomous?
i'm keeping Sicarius terrosus (Chile) and Sicarius hahnii (Namibia). luckily i never had to figure it out by myself, but i heard it's very dangerous. necrotoxic venom!!!

Can they climb glass?
no (if glass is clean :) )

I heard they are communal?
no! i tried to keep five juvenile S. terrosus together, i separated the remaining two the day after.

Are they as fast as i hear, like P. murinus fast, or faster?
my Sicarius aren't very fast and not extremely agressiv. more or less a 'boring spider' compared to a P. murinus. the hide under sand the whole day, if you're lucky you'll see them at night.
few pics (only juvenile, i didn't had any adults when i took the pics):
scorpions.f1.to/?n1=92_Sicarius&n2=40_Sicarius_hahni
scorpions.f1.to/?n1=92_Sicarius&n2=70_Sicarius_terrosus
 

Venom

Arachnoprince
Old Timer
Joined
Jul 21, 2002
Messages
1,700
Very informative post. :worship: I'm always interested by animals that keep humanity in check. We shouldn't be too arrogant. May I ask what your source is?
"Sicarius venom can cause disseminated intravascular coagulation with renal failure."

Cited from:

http://books.google.com/books?id=20...&hl=en&sa=X&oi=book_result&resnum=5&ct=result

"Autopsies (of test rabbits) revealed extensive subdermal tissue damage and patechial haemorrhages in the liver, lungs and heart"

Cited from:

http://www.spiderclub.co.za/medical.html

"It is striking that venoms of L. laeta and Sicarius yielded an order of magnitude more total venom protein upon electrostimulation than the other Loxosceles species surveyed (Table 1). Furthermore, SMD activity per unit total venom protein was comparable between these species and the Loxosceles species that have well-documented and serious dermonecrotic effects on human tissues. If the severity of lesion formation is positively correlated with absolute amounts of SMD, bites from L. laeta and Sicarius may be capable of inducing more severe reactions than other species. Analyses of the effects of Sicarius venoms in rabbits indicate that dermenecrotic lesions develop more rapidly after Sicarius bites than after bites of South African Loxosceles (Newlands, 1982; Newlands and Atkinson,
1990a). In fact, some African researchers have touted Sicarius as the most dangerous spider known; however, the biology of these animals makes human envenomation events rare."

Cited from:

http://www.lclark.edu/~binford/SMDDistribution copy.pdf

"Six-eyed sand spiders have a virulent cytotoxic poison capable of destroying tissue around the site of the bite and throughout the body, causing massive internal bleeding. Tissue damage from a bite can be extensive and severe, but bites to humans are not well documented. However, under experimental conditions, rabbits envenomated with Sicarius venom died within 4-6 hours and autopsies revealed extensive damage to subdermal tissue and skeletal muscle. Also, there was swelling of the liver and damage to heart and kidney tissues as well as blocked arteries in the lungs."

Cited from: http://www.afpmb.org/pubs/Field_Guide/field_guide.pdf


You might also check out:

Kurpiewski, Gretchen et al. “Platelet Aggregation and Sphingomyellnase D Activity of a Purified Toxin from the Venom of Loxosceles Reclusa.” Toxicology, vol. 96, pp. 166-167 (1982).


And for a laugh: I'm not the first to compare the effects of Sicarius envenomation with Ebola,

http://www.sciencedirect.com/scienc...serid=10&md5=1bd0fe24c3b455858fdb3007f2fb94b3
 

Chris Newman

Arachnopeon
Joined
May 18, 2008
Messages
3

buthus

Arachnoprince
Old Timer
Joined
Jun 8, 2006
Messages
1,381
Recently acquired 6 x Sicarius sp.
One climbed a plastic container out into the work tray ...couldnt find it at 1st and started to panic a bit ...hate to loose one in the room. It was able to climb the plastic only because the walls were dusty when I misted, creating a grip-able surface.
They are also capable of extremely quick bursts of speed ...which can propel them up a slick surface ...just keep that in mind when considering housing. ;)
 

Venom

Arachnoprince
Old Timer
Joined
Jul 21, 2002
Messages
1,700
So in order to sum this up, what you are saying is getting bitten by one of these critters is really, really not a good idea!

Unless you are interested in spider-assisted suicide! Otherwise, yeah, it's a bad idea.


I'm sure glad it turns out these CAN'T climb glass! That's been one of the saving graces of the level 5 scorps--they're fast and toxic, but easily contained. A sensibly tall enclosure with clean glass should then ensure a pretty solid containment. However, the said enclosure should obviously be a hands-out, tongs-only environment, lol. :D


Buthus, could you post pictures of their enclosures? I'm thinking we could make this thread a good Sicarius guide sticky for the forum. Seeing as these are the first true spiders consistently in the US hobby to be equal with level 4 - 5 scorpions, it might be appropriate to have a special info/ guidelines sticky, for the good of all concerned.
 

What

Arachnoprince
Old Timer
Joined
Jul 13, 2006
Messages
1,150
So far mine seems to be doing well on sugar sand(really fine white sand) in a 16oz delicup with lots of ventilation...

Only care is adding roaches and removing the remains, watering is not recommended as the only time I have given mine water it refused to even settle down against the sand. These can take roaches that are 1-2 times as large as their bodies and will happily take down more than one at a time.

Other than that dont be surprised if it tries to run up the sides of the container whenever it is disturbed. :cool:
 

blacktara

Arachnobaron
Old Timer
Joined
Jan 23, 2005
Messages
355
This is a little off topic but not much. I went to a talk just last week on that addressed necrotic arachnidism

The talk was actually about Crofab for NA Crotalid bites but the man who gave the talk is director of Poison Control for Oklahoma and did his toxiocology fellowish in Arizona so he has a LOT of experience with snakebite and spider bite and he did a small section on arachnid envenomations after the main part of the talk

He got my attention immediately because he was the first physician other than myself I have heard make it very clear that you can NOT positively identify recluses (reclusae?) (recleeseses?) - (what IS the plural of brown recluse anyway?) without looking at detail like eye pattern (I cant you how many colleagues will swear that they can spot a fiddleback a mile away and look at me like I;m nuts when I say you cant be sure that easily)


Turns out that some of the stuff that physicians have been doing for recluse bites is not beneficial or even harmful. For example they used to give Dapsone (and I have done this too) - no good. Some folks were doing wide excision of a bite in the theory that it would prevent necrosis - in most cases you end up with more disfigurement from the prophylactic surgical excision than you would from the bite. In the end, a lot of recluse bites end up being not bad, but the ones that are bad can be really bad

The Crofab talk was interesting as well. Crofab has been reformulated - it used to be made from a couple of North American species and then Fer-de-lancer and another tropical (I forget which). It's now all NA Crotalids, INCLUDING Mojave. Interestingly, it's activity is marjkedly decreased against a couple of species - Southern Pacific and Blacktail (O Helleri and Molossus) - tho the Crofab insert still refers to it as V Helleri - It's also interesting to note what anecdotal reports of what seems to be neurotoxin activity (weak) in C Horridus.

Anyway, a most interesting talk - like I said a little off topic
 

buthus

Arachnoprince
Old Timer
Joined
Jun 8, 2006
Messages
1,381
...they used to give Dapsone (and I have done this too)...
I shouldnt even be at my puter right now ...no time.. but.. blacktara, I would love to converse a bit about this subject in the near future.
 

blacktara

Arachnobaron
Old Timer
Joined
Jan 23, 2005
Messages
355
This is a little off topic but not much. I went to a talk just last week on that addressed necrotic arachnidism

The talk was actually about Crofab for NA Crotalid bites but the man who gave the talk is director of Poison Control for Oklahoma and did his toxiocology fellowish in Arizona so he has a LOT of experience with snakebite and spider bite

Turns out that some of the stuff that physicians have been doing for recluse bites is not beneficial or even harmful. For example they used to give Dapsone (and I have done this too) - no good. Some folks were doing wide excision of a bite in the theory that it would prevent necrosis - in most cases you end up with more disfigurement from the prophylactic surgical excision than you would from the bite. In the end, a lot of recluse bites end up being not bad, but the ones that are bad can be really bad

The Crofab talk was interesting as well. Crofab has been reformulated - it used to be made from a couple of North American species and then Fer-de-lancer and another tropical (I forget which). It's now all NA Crotalids, INCLUDING Mojave. Interestingly, it's activity is marjkedly decreased against a couple of species - Southern Pacific and Blacktail (O Helleri and Molossus) - tho the Crofab insert still refers to it as V Helleri - It's also interesting to note what anecdotal reports of what seems to be neurotoxin activity (weak) in C Horridus.

Anyway, a most interesting talk - like I said a little off topic
 
Top