Uricating hairs / OW / NW

ballpython2

Arachnoprince
Old Timer
Joined
Feb 28, 2007
Messages
1,671
Ok I need some help can someone tell me where I can get a full list of all the tarantulas that have uricating hairs and the ones that don't.

Also, if you can put at the top of lists Old world or new world because I get alll these mixed up. thank you.

And how did it come about that one of these species (for a lack of better termenology) ended up being born with uricating hairs anyway?

And with uricating hairs some can be shot off? and others are rubbed off? or they all come off the same way??
 

ErikH

Arachnoangel
Old Timer
Joined
Mar 8, 2006
Messages
841
Only NW tarantulas have urticating hairs.

Tarantulas of these genus (geni???) can flick hairs:
Acanthoscurria
Brachypelma
Grammostola
Nhandu
Lasiodora
Theraphosa

Avicularia have urticating hairs, but rub their bodies against a predator to push them in rather than flick them.

Psalmopoeus have no urticating hairs.

I am sure someone else can post the the other NW species I have not covered.
 

P. Novak

ArachnoGod
Old Timer
Joined
Sep 12, 2005
Messages
6,234
All New World tarantulas have uricating hairs:

Avicularia spp.
Aphonopelma spp.
Acanthoscurria spp.
Brachypelma spp.
Cyclosternum spp.
Grammostola spp.
Nhandu spp.
Sericopelma spp.
Chromatopelma spp.

there are more but Im not to lazy to think and search right now

All Old World tarantulas don't have uricating hairs:

Pterinochilus spp.
Ceratogyrus spp.
Heteroscorda spp.

again to lazy to list the rest. Plus there are species that are rarely in the hobby.


The New World tarantulas(the ones with uricating hairs) probably had to evolve due to predators or something
 

GoTerps

Arachnoking
Old Timer
Joined
Sep 18, 2003
Messages
2,115
Hi Novak,

All New World tarantulas have uricating hairs:
This is not true. All members of the subfamily Ischnocolinae lack urticating hairs. This subfamily is represented in the NW by the following genera:

› Hemiercus
› Holothele
› Oligoxystre
› Proshapalopus
› Pseudoligoxystre
› Sickius


Tapinauchenius and Psalmopoeus lack them as well.

Eric
 

hcsk8ter

Arachnopeon
Joined
Jan 7, 2007
Messages
43
By the way, I myself have no allergies (that I know of), am not allergic to bee stings, but I find urticating hairs EXTREMELY itchy and annoying. Watch out and use masking tape.
 

P. Novak

ArachnoGod
Old Timer
Joined
Sep 12, 2005
Messages
6,234
Hi Novak,



This is not true. All members of the subfamily Ischnocolinae lack urticating hairs. This subfamily is represented in the NW by the following genera:

› Hemiercus
› Holothele
› Oligoxystre
› Proshapalopus
› Pseudoligoxystre
› Sickius


Tapinauchenius and Psalmopoeus lack them as well.

Eric

HEy thanks for correctiing me, I knew there was something that wasnt quite right.
 

EricFavez

Arachnosquire
Old Timer
Joined
Dec 13, 2006
Messages
124
To give you a clear separation of the two...your NW TS are the ones that are found in US..Central and south America...you know what we commonly call the New World. The OW Ts are gonna be your Asian...African ...etc. If you have not noticed your OW spiders tend to be a lot more aggressive than the others and that is because they lack the urticating hairs and their only defense is to bite..and sometimes their venom is more potent than the average T....hope that helps a lil BP
 

massmorels

Arachnobaron
Old Timer
Joined
Mar 3, 2007
Messages
336
Im to the point where Im phasing the new worlds out of my collection because Im so sensitive to urticating hairs.. for example.

 

Nitibus

Arachnodemon
Old Timer
Joined
Feb 7, 2007
Messages
728
Holy Crap Morels !!! That's nasty !

Stop cuddling your T's for crying out loud !
 

ember

Arachnosquire
Old Timer
Joined
Feb 13, 2007
Messages
129
Okay seriously... how the HELL did you get those all over yourself, man? Is it just a full-body allergy response, or did you somehow piss off a spider while cuddling or something? I ask because I care. Heh...
 

Cerbera

Arachnobaron
Old Timer
Joined
Mar 12, 2005
Messages
540
Only NW tarantulas have urticating hairs.
Avicularia have urticating hairs, but rub their bodies against a predator to push them in rather than flick them.
Off to the left again, briefly if you don't mind...

I wonder why on earth Avics evolved like that ?! To only be able to 'push' your urticating hairs into anything effectively, hasn't the spider got to be virtually IN the mouth of whatever is trying to eat it !? And is that actually an effective defence ?

Does anyone concur with me that this might be the reason why avics are particularly keen to risk a big jump to get away from threat sources in a perhaps greater way than other spiders that are capable of the same jumps, but generally don't (Ephebopus & Poecilotheria are the only 2 in my collection that can but don't so far)...
 

Nitibus

Arachnodemon
Old Timer
Joined
Feb 7, 2007
Messages
728
" I wonder why on earth Avics evolved like that "


The first unknown we have to consider : Did this evoluntonary advantage come from a need, or was it a random mutation ?

I don't know, but I always thought a NW T's could only shoot it's hairs paraelle to itself, and up. Not being able to shoot them down would offer little defence to avic t's


I think we also need to indentify the predators of Avics : From what I assume their biggest predators would probably be snakes / reptiles and primates. I can't see this defence being good against snakes : they just strike and that's it, but a primate may try to play with the avic first... Just an idea
 

GoTerps

Arachnoking
Old Timer
Joined
Sep 18, 2003
Messages
2,115
Hi Cerbera,

Off to the left again, briefly if you don't mind...

I wonder why on earth Avics evolved like that ?! To only be able to 'push' your urticating hairs into anything effectively, hasn't the spider got to be virtually IN the mouth of whatever is trying to eat it !? And is that actually an effective defence ?
Some Avicularia have been documented to "kick" hairs (A. verisicolor).

BERTANI, R., T. BOSTON, Y. EVENOU & J. P. L. GUADANUCCI (2003). Release of urticating hairs by Avicularia versicolor (Walckenaer, 1837) (Araneae, Theraphosidae). Bulletin of the British Arachnological Society 12 (9): 395-398.

Eric
 

PhilR

Arachnoknight
Old Timer
Joined
Mar 21, 2006
Messages
201
Some Avicularia also incorporate urticating hairs into their tube webs, presumably to deter predators.
 

tarcan

Arachnoking
Old Timer
Joined
Mar 8, 2003
Messages
2,098
Eric,

I thought Hemiercus genus was Theraphosinae? Maybe I am wrong, I have them listed as such in two different books, maybe they were changed? Can you or anyone else confirm?

Martin
 

GoTerps

Arachnoking
Old Timer
Joined
Sep 18, 2003
Messages
2,115
Hi Martin

Eric,

I thought Hemiercus genus was Theraphosinae? Maybe I am wrong, I have them listed as such in two different books, maybe they were changed? Can you or anyone else confirm?

Martin
They are firmly in the Ischnocolinae as far as I know.

The most recent change was Rudloff removing their synonymy with Holothele in 1997.

Eric
 

Cheshire

Arachnoking
Old Timer
Joined
Jul 7, 2005
Messages
3,160
Off to the left again, briefly if you don't mind...

I wonder why on earth Avics evolved like that ?! To only be able to 'push' your urticating hairs into anything effectively, hasn't the spider got to be virtually IN the mouth of whatever is trying to eat it !? And is that actually an effective defence ?

Does anyone concur with me that this might be the reason why avics are particularly keen to risk a big jump to get away from threat sources in a perhaps greater way than other spiders that are capable of the same jumps, but generally don't (Ephebopus & Poecilotheria are the only 2 in my collection that can but don't so far)...

As a last second defense to irritate the lining of the mouth and throat in a similar manner a bad taste would.

Although, I do agree with you that their method of dispersal could have something do do with that.
 

tarcan

Arachnoking
Old Timer
Joined
Mar 8, 2003
Messages
2,098
Hi Martin



They are firmly in the Ischnocolinae as far as I know.

The most recent change was Rudloff removing their synonymy with Holothele in 1997.

Eric
Eric,

That is exactly it, Rudloff paper (page 6) removes Hemiercus from synonymy with Holethele and places the genus into the theraphosinae sub-family. I knew I should have dropped the books and just checked the paper, thanks for reminding me.

Does not change the fact that they lact urticating hair and still belongs in the list of NW species without UR.

What about Catumiri? Since some members of the genus used to be in Oligoxystre, maybe they also lask urticating hair? I do not have the papers and do not know about this genus, but just wondering.

Martin
 

GoTerps

Arachnoking
Old Timer
Joined
Sep 18, 2003
Messages
2,115
Martin,

What about Catumiri?
My mistake!:wall: Yes, these are ischnocoline spiders.

That is exactly it, Rudloff paper (page 6) removes Hemiercus from synonymy with Holethele and places the genus into the theraphosinae sub-family.
Yeah, I just looked that over. Well, if Hemiercus are theraphosine spiders, then I have some questions about what I have as Hemiercus. I don't think what I have from Venezuela is a theraphosine. However, it wouldn't surprise me that the spider you have pictured from French Guyana is a theraphosine.

Of course the Ischnocolinae has been where species get stuck when they don't fit nicely into one of the other subfamilies. Following Raven 1985, some current ischnocolines are more closely related to theraphosines then to other ischnocolines! But they'll be made into at least 2 groups eventually.

Eric
 
Last edited:
Top