Myths about sizes of spiders

Cemykay

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Hey guys, i´m kind of curious if there is any truth to the myth of a 10inch LP or a 12 inch Theraposa?
What are your experiences? Do you have a tarantula which comes close to those claimed sizes? If you have, please show me in this thread :)
My three year old LP recently molted and is about 18-19cm now and she is huge fo me
 

testdasi

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Hey guys, i´m kind of curious if there is any truth to the myth of a 10inch LP or a 12 inch Theraposa?
What are your experiences? Do you have a tarantula which comes close to those claimed sizes? If you have, please show me in this thread :)
My three year old LP recently molted and is about 18-19cm now and she is huge fo me
It's more complex than just calling it a myth. Sort of the entwinement of human nature and the tarantula hobby.

There isn't a standard way of measuring the size of a tarantula.
  1. You can measure it diagonally (e.g. tip front left leg to tip of back right leg), which usually gives you the largest measurement but requires more effort.
  2. You can measure it sideway (tip front leg to tip back leg on the same side), which is usually easiest for a keeper to perform.
  3. You can even measure body length, which will give you a very consistent albeit less impressive number.
This is the 1st area where human nature comes in.
People like to boast, even more so in the tarantula hobby which is male-dominated. "My manhood is bigger than yours" is something evolution has imprinted on hu-men's minds for ages and is hard to erase.
When it comes to tarantula keeping, it becomes my T is bigger than yours. Since it's way more impressive to say you have a 25cm (DLS) tarantula rather than a 10cm (body length) tarantula, people naturally lean towards using (1).

Breeders / sellers intentionally or unintentionally exacerbate the situation by being rather optimistic with their measurement. (1) is quite labour intensive (try sliding a ruler under any tarantula and telling it to sit still) so is practically not possible. Hence, 2 workarounds were created:
  • Moult measurement. Since one can safely assume a tarantula is definitely bigger than its moulted skin, measuring the moult would, on paper, seem like a safe conservative measurement. Except for the fact that a tarantula would never lay fully stretched out flat like its moult. The tarantula may crunch up, spread out and every thing in between but never completely flat.
  • Guesstimation from (2). Geometry would dictate that (1) would be larger than (2). So a quick (2) can be roughly measured then add a certain % on top to get to DLS. But how much more? A back-of-the-envelope calculation says it can be anything from 2% (Pokies - they like to keep their legs together in a rough 1:5 rectangle) to 10% (how my LP likes to sit, roughly a 1:2 rectangle) to a theoretical maximum of 41% (a square).
  • There are other workarounds (e.g. from body length using body-leg ratio or just eye ball it etc.) but they are not as common.
Here I'm not saying breeders / sellers are dishonest. It's a practical limitation based on their customers' preference so something has to be done to deal with it.
And eventually that becomes a sort of "standard" that the hobby follows, despite the presence of an elephant (i.e. body length measurement).

With that long background in mind, let's talk the 10" LP / 12" Theraphosa. This is the 2nd area where human nature comes in.
In the same "my manhood is bigger than yours" vein, it's hard to admit you have a smaller T.
So every claim of a large T is always met with excessive doubt, mostly "I'll believe it when I see it", which I can't blame them because I'd say the same.
We all conveniently just ignore the fact that "we all do it" when it comes to optimistically measuring a tarantula but still demand stringent scientific standard of proof for large specimen claims.

That eventually create "the myths" that aren't exactly mythical.
Using your 18-19cm measurement, for example. You said your LP "recently molted" so I would assume the measurement was measured from the moult. That tarantula probably looks closer to 15cm sideway so I doubt you would be able to produce photographic evidence of its 19cm size.
Is the 19cm specimen a myth? It isn't because you know for sure you have one.
 

Cemykay

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Thank you for your nuanced post! It´s true that there is a inconsistent method of size measurement in the tarantula hobby.
In germany we use body length as the standard most of the time. Sometimes diagonal leg span is used, but mostly for boasting ;).

Your valid points about measurements aside, do you know anyone who can back their claim for 10inch/25cm DLS Lasiodora/ Theraposa?

It's more complex than just calling it a myth. Sort of the entwinement of human nature and the tarantula hobby.
This is the 1st area where human nature comes in.
People like to boast, even more so in the tarantula hobby which is male-dominated. "My manhood is bigger than yours" is something evolution has imprinted on hu-men's minds for ages and is hard to erase.
When it comes to tarantula keeping, it becomes my T is bigger than yours. Since it's way more impressive to say you have a 25cm (DLS) tarantula rather than a 10cm (body length) tarantula, people naturally lean towards using (1).
I guess we all like to exaggerate sizes to outsiders to make our tarantulas appear a bit more "intimidating" or "dangerous" aswell :D

Breeders / sellers intentionally or unintentionally exacerbate the situation by being rather optimistic with their measurement. (1) is quite labour intensive (try sliding a ruler under any tarantula and telling it to sit still) so is practically not possible. Hence, 2 workarounds were created:
  • Moult measurement. Since one can safely assume a tarantula is definitely bigger than its moulted skin, measuring the moult would, on paper, seem like a safe conservative measurement. Except for the fact that a tarantula would never lay fully stretched out flat like its moult. The tarantula may crunch up, spread out and every thing in between but never completely flat.
  • Guesstimation from (2). Geometry would dictate that (1) would be larger than (2). So a quick (2) can be roughly measured then add a certain % on top to get to DLS. But how much more? A back-of-the-envelope calculation says it can be anything from 2% (Pokies - they like to keep their legs together in a rough 1:5 rectangle) to 10% (how my LP likes to sit, roughly a 1:2 rectangle) to a theoretical maximum of 41% (a square).
  • There are other workarounds (e.g. from body length using body-leg ratio or just eye ball it etc.) but they are not as common.
Here I'm not saying breeders / sellers are dishonest. It's a practical limitation based on their customers' preference so something has to be done to deal with it.
And eventually that becomes a sort of "standard" that the hobby follows, despite the presence of an elephant (i.e. body length measurement).
Had that surprise with a polish shop keeper, who described a female with a size of 5cm (with that measurement of germans in mind) which i thought would be an adult. It turned out to be 5cm dls..

That eventually create "the myths" that aren't exactly mythical.
Using your 18-19cm measurement, for example. You said your LP "recently molted" so I would assume the measurement was measured from the moult. That tarantula probably looks closer to 15cm sideway so I doubt you would be able to produce photographic evidence of its 19cm size.
Is the 19cm specimen a myth? It isn't because you know for sure you have one.
To your question: Yes it was an estimate, based on the molt i pulled out which was 17,5 cm in diagonal leg span. I just added 5-10% as a rough guess.:geek:
 

testdasi

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Thank you for your nuanced post! It´s true that there is a inconsistent method of size measurement in the tarantula hobby.
In germany we use body length as the standard most of the time. Sometimes diagonal leg span is used, but mostly for boasting ;).

Your valid points about measurements aside, do you know anyone who can back their claim for 10inch/25cm DLS Lasiodora/ Theraposa?
I had a 10" LP but with no photographic evidence. ;)

My current LP is 8.5cm (3.35") in body length but unfortunately only 14cm (5.5") in "photographically evidenced" DLS since it refused to stretch its legs.
Its guestimated size is 18cm (7") until I can get a moult.

LP Size 02 Small.jpg
 

Venom1080

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9" Lasiodora is the largest ive seen on a tape.
10" rufilata
Theraphosa are typically 10.5" max. But i saw one male over 11". Think it was a blondi.
 

RezonantVoid

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People absolutely flip when they learn aussie tarantulas dont actually have a 5ft legspan
 

The Grym Reaper

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Biggest LP I've ever seen was 8.5" DLS at full stretch, both of my girls were a little over 7".
Biggest Theraphosa I've seen was just over 10".
 

SharkNATO

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Hard to get sense of scale but if you told me the LP at 12:25 in this video is 9"-10" legspan I would believe you

 

KaroKoenig

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Hard to get sense of scale but if you told me the LP at 12:25 in this video is 9"-10" legspan I would believe you
That one immediately came to my mind as well. Awesome channel, by the way. A must for every tarantula enthusiast.
 

Asgiliath

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Doesn't answer the question but my stirmi is the biggest T i've ever seen In person and she is about 8 inches DLS.
 

SonsofArachne

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Then there's the opposite side of the coin - LP haters who tell you 7.5 inches DLS is max size for one. My female is easily 7 inches and still growing.
 

RadicalSquire7

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I have a 7.5in P. Metallica a 11.5 in T. blondi and no LP but do have a almost 11in P. ornata but she hides and destroys all her molts she was only photoed once since I’ve had her for 2 yrs and I don’t have any photos anymore because they were all blurry because she was on the run
 

jrh3

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I have a 7.5in P. Metallica a 11.5 in T. blondi and no LP but do have a almost 11in P. ornata but she hides and destroys all her molts she was only photoed once since I’ve had her for 2 yrs and I don’t have any photos anymore because they were all blurry because she was on the run
In a previous post you said you were getting your first Pokie and wanted advice, but here you say you have a metallica and ornata.

You also stated you kept a P. Cambridgei and a T. Vagans as your only other tarantulas, then here you say you have a blondi as well.

Here is your exact post word for word, “ I mean if my mom let me get it as a first tarantula I would have been in some deep water but no I had a P. Cambrigei before this and before him I had a T. Vagans. So 3rd tarantula I know I might seem like a newbie but am pretty knowledgeable about T’s”.

No need in making lies bud, you would not need advice if you had kept a Pokie before.
 

RadicalSquire7

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You know what you got me but let me explain my reasoning. I thought everyone was just going to be a bunch of jerks on here so I wanted to sound like I had a bunch of big T’s so I wouldn’t be made fun of and called a newbie. Mostly because I’m not as new as you would think and because I kept other venomous animals before my tarantulas. I hope you understand if not oh well
 

jrh3

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You know what you got me but let me explain my reasoning. I thought everyone was just going to be a bunch of jerks on here so I wanted to sound like I had a bunch of big T’s so I wouldn’t be made fun of and called a newbie. Mostly because I’m not as new as you would think and because I kept other venomous animals before my tarantulas. I hope you understand if not oh well
I will give you 2 life lessons to take away from this....

1. Always tell the truth.

2. Not having experience doesn’t make you any less if a keeper than anyone else.

Don’t take people as being jerks, take it as they care about the hobby and don’t want a bad name for the ones that don’t understand the hobby. All it takes is a kid being bit and hospitalized, then his parents push it to the officials and try to get more species banned.
 

RadicalSquire7

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I will give you 2 life lessons to take away from this....

1. Always tell the truth.

2. Not having experience doesn’t make you any less if a keeper than anyone else.

Don’t take people as being jerks, take it as they care about the hobby and don’t want a bad name for the ones that don’t understand the hobby. All it takes is a kid being bit and hospitalized, then his parents push it to the officials and try to get more species banned.
I understand my parents aren’t the ones who would pass it or to the officials they would just go get me pain killers for the bite and say it’s my fault the tarantula bit me. I was almost bit by my T. Vagans before he died on Christmas last year. So I hope that I don’t get bit but really how bad is the bite to a asmatic? Compared to like a regular person?
 

KaroKoenig

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how bad is the bite to a asmatic? Compared to like a regular person?
Unknown, but chances are it can be worse than for a healthy individual.

If you plan on keeping on lying in other situations of your future life, you seriously need to get better at it... :smug:
 

RadicalSquire7

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Unknown, but chances are it can be worse than for a healthy individual.

If you plan on keeping on lying in other situations of your future life, you seriously need to get better at it... :smug:
I’m not as good as I used to be at it🤣🤣. But yeah not sure about getting bit but I’m pretty careful about rehouses and other such things. The only scary thing is watering time my last T hated water.
 

jrh3

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I’m not as good as I used to be at it🤣🤣. But yeah not sure about getting bit but I’m pretty careful about rehouses and other such things. The only scary thing is watering time my last T hated water.
Were you spraying the tarantula?
 
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