T.blondi ( is it truly the largest tarantula?)

Ungoliant

Malleus Aranearum
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After thinking about this for a minute, I have to change my response to the most accurate way to measure a tarantula. I'm aware that in the scientific community body length is used, but in keeping tarantulas or other spiders and arachnids as pets perhaps leg span needs to stay the standard. Only because one needs to know the leg span in order to provide an appropriate sized container to house it in.
I wouldn't suggest trying to overthrow the existing convention of using legspan, as 1) keepers are so accustomed to using that substituting body length would cause confusion and 2) legspan is a useful metric for determining appropriate dimensions in an enclosure (as you mentioned). But it could be interesting to include body length alongside legspan.


I don't know why diagonal leg span is ever used though. Measuring from one side seems to be sufficient.
I think this was simply chosen as the metric that produces the biggest (most impressive) number.
 

Olan

Arachnoangel
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Hello fellow hobbyists,

I have always been very interested in the large fast growing species. So I've got plenty of the big new world terrestrial species such as : T.Stirmi, A .Geniculata, L.parahybana, L. Difficilis, N. Chromatus and P. Cancerides.

But one spider I don't own is the true T. Blondi because they are super expensive here in Canada and they are so similar to the stirmi. Do they really get any bigger? From what I've read it's the T. Blondi and T. Apophysis that get the biggest. Is there any truth to this? Is it worth buying at 350$ a sling? I have a 5 inch female stirmi thats grown like a weed and she's arguably the my favorite spider species in terms of growth and feeding response. So to all who have experienced within the genus I would love to hear if your stirmi got as big as your other theraphosa.

Thanks and good day
OP, you like the large, fast growing species but don't mention Pamphobeteus? Surely you have some right???
 

sdsnybny

Arachnogeek
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Apr 29, 2015
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Looking at the inch tick marks compared to the cm marks it appears to be about 11" still pretty big
 

8legfreak

Arachnosquire
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Nov 19, 2016
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62
Its still a big 9.5" T.... :vomit:

Looking at the inch tick marks compared to the cm marks it appears to be about 11" still pretty big
11 inches = 27.9 cm

So... Does anyone know how big the average skateboard is? :bag:
 
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Philth

N.Y.H.C.
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SERIOUSLY???? No one noticed the 11 and 12 were photo-shopped? None of you other metric users know that 20cm equals about 8"???? FAKE NEWS!!!
lol, I'm surprised no one else picked up on that, although I suspect @AphonopelmaTX did. I was far to lazy to change the CM lol, and I figured on a American based board, most people wouldn't notice. Bottom line, don't believe everything you see or read on the internet ;)

To reiterate a few things that have already been said in this thread.
  • Female tarantulas molt their whole life, but at some point reach their max size and stop growing.
  • Power feeding will make them, grow quicker, but not larger in the long run.
  • A young Theraphosa may grow 1-2 inches in a molt that may seem ridiculous. But that slows down, and at some point adult spiders stop growing , even after a molt.
  • The "12 inch" T. blondi that Robc had was actually a T. stirmi, but back then everyone called them T. blondi.
  • The "12 inch" T. stirmi that Robc had was never measured on a ruler, and was likely barley 10 . He even claimed in one of the videos of it molting that it must be close to 14 inches post molt, under the misunderstanding that they continue to grow as adults. (Much like we saw in the misinformed beginning of this thread)
  • I've owned adult females of all three species of Theraphosa, and for me, the biggest spiders I've ever seen in my life were WC T. stirmi.
  • I've never see a spider or a picture of a spider/molt more then 10.5 inches
  • 12" spiders don't exist.
  • 11" spiders don't exist.
  • A molt stretched out to reach ten inches, is only about 7-8 inches in a spiders normal resting position.
Now that the cat is out of the bag, here is the real photo of what is my current largest spider. A adult female T. apophysis. When this spider molted I was certain it was over ten inches. But I even fooled myself, rulers don't lie. Men tend to over exaggerate size lol :astonished:


Later, Tom
 

Nightstalker47

Arachnoking
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Well I didn't realize this thread was still going strong. I read through all the posts and I now understand where I may have been off.

So I guess from everyone here's point of view a spider cannot outgrow a sibling in the long run, only that powerfeeding enables them to get to that size faster.

I am aware that females continue to molt until their death. I am aware that males have limited molts, having had many mature under my care. I still think the term infinite molts is wrong in its wording and that the person who said this " fact" was speaking in a general manner as he said Tarantulas and not females. I never said that P. Ornata and LP get to 10 inches. I'm only speculating on the possibility of what I think may impact the animal. I thinks it's self explanatory, If you don't feed a T for a whole year and feed another all year the underfed sling will have stunted it's growth and lost much of his potential. He will not grow to the same size. It's easy to say oh no the other one only grew faster it won't get any bigger... in my experience it does generally lead to a larger final size, in mature males only.

I'm a big fan of your blog and YouTube channel Tom. Although you may not agree, Im honored to see that you chimed in.

I only wanted to hear if anyone else had experienced a similar situation. I've had LP slings in the past that were bought with a friend. He only bought one and I bought several yet when I saw his specimen months later it was drastically smaller then all of my slings. Here's where it gets interesting, his LP turned out to be male and it was a small 5 inch mature male. I still have a male bought about 2 years ago, I was going to send him out but he was an exceptional spider and I became attached. Well he matured and he's a minimum of 7 inches probably bigger. I'm going to get him out and attempt to measure. But he was from the same eggsac, and i know that my friend didnt feed regurlarly. Long story short, the final size of my male was quite bigger then his , which i belive was impacted by the way I was keeping it. I could be wrong.

I'm open to all of your opinions and I'm not saying that I have it all figured out but I definitely feel like I'm on to something.

Thanks for all the responses. I'm always interested in your point of views and personal experiences.

Here'sa pic of my big male Lp. Very hard to get him to stretch out but you can tell he's a big boy.
 

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Philth

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I'm a big fan of your blog and YouTube channel Tom. Although you may not agree, Im honored to see that you chimed in.
Just to be clear, I'm not that Tom lol. His popularity on YouTube seems to be growing, because I find myself being confused with him more and more. He's a much nicer person then I am, so I would feel bad if people think I'm him lol.

I don't think anyone would disagree that mature males can vary in size. Its pretty well known, and I've heard some interesting theory's on maybe why that is. Anyways, although very different then Theraphosa, take a look at these to Cyriocosmus mature male brothers from the same sac. I've seen it in many genera from species across the world.



Later, Tom
 

Nightstalker47

Arachnoking
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Oh sorry man my mistake.That's really weird, I haven't owned this species but are you certain the smaller male is mature? He looks different in coloration, if he is then that would suggest some large genetic variation between them. Very interesting, did you keep them at the same temps and feed them the same amount?
 

Philth

N.Y.H.C.
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100% positive its mature. I may not be the Tom you were hoping for, but I know what I'm doing lol.

Same temps, same feeding schedule. The larger one matured a year later.

Later, Not your Tom lol.
 

Ran

Arachnoknight
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Mar 16, 2011
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282
Tom, that is a beautiful apophysis girl! I have an 8" girl that is all legs. Great T's :)
 
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