undiscovered T leg span

spid142

Arachnobaron
Old Timer
Joined
Apr 9, 2006
Messages
492
Ive wondered, with undoubtedly many T species still to be discovered somewhere, what do you think, would be the maximum LS that a T is likely to be found, realistically taking into consider what we know about T bodies' limits on falls, and the fact they work partially on hydraulic pressure for leg extension etc. My estimation would be a maximum size of between 13 and 14-inch leg span, I think 15-inch would be stretching it. I just dont think Ts could really exceed that size, given how they are constructed. What is everyones best estimate and why?
 

P. Novak

ArachnoGod
Old Timer
Joined
Sep 12, 2005
Messages
6,218
Ive wondered, with undoubtedly many T species still to be discovered somewhere, what do you think, would be the maximum LS that a T is likely to be found, realistically taking into consider what we know about T bodies' limits on falls, and the fact they work partially on hydraulic pressure for leg extension etc. My estimation would be a maximum size of between 13 and 14-inch leg span, I think 15-inch would be stretching it. I just dont think Ts could really exceed that size, given how they are constructed. What is everyones best estimate and why?
I don't think a T could exceed 12-13". Their bodies just wouldn't be able to function if they were any bigger. Inverts only have a limited size because of the way they take in the oxygen.
 

bliss

Arachnoprince
Old Timer
Joined
Sep 25, 2006
Messages
1,170
I agree with novak. Their exoskeleton can only contain so much, the volume must not overcome the maximum surface area of their exoskeleton. If you ever get the chance to watch certain cells under a microscope, they follow the same guidelines -- they never get HUGE because if they do, they'll lyse (burst). Their volume will overcome how far the cell membrane can stretch.

however, this is just my hypothesis, i really have no clue. individual cells are quite different from T's, i know.... i just wonder if this is the case for T's too?

then again there may be a T that has evolved to where its Exoskeleton can stretch to 15", we just don't know yet. but however we are -pretty sure- that they can't get over 13". but hey, you never know....
 
Last edited:

neanyoe

Arachnosquire
Old Timer
Joined
May 17, 2007
Messages
66
just a random question that I want to know about, How big were prehistoric inverts/ spiders/ ....tarantulas?
 

Merfolk

Arachnoprince
Old Timer
Joined
Dec 13, 2005
Messages
1,323
I've read avout 30-40 cm, bigger in other orders of arachnids.

They are stories of very big T apophysis but, as long they didn't catch and measure à 14 inches specimen, few will believe they exist.
 

Drachenjager

Arachnoemperor
Old Timer
Joined
Jan 23, 2006
Messages
3,509
I've read avout 30-40 cm, bigger in other orders of arachnids.

They are stories of very big T apophysis but, as long they didn't catch and measure à 14 inches specimen, few will believe they exist.
there is no telling what is out there. God(or nature if you prefer)likes to put us in our place sometimes by taking what we know and proving it wrong. Sometimes we call it anomolies , sometimes we actually admit we were wrong.
Could there be a 15+inch tarantula? Maybe ,i wouldnt doubt it.
I am sure there are those who could use what we know about Tarantula anatomy and the laws of physics and calculate a theoretical maximum size. Maybe they already have, but that dosent mean it would be right.
 

omni

Arachnobaron
Joined
Apr 30, 2007
Messages
382
With selective breeding, size could be increased, but it would take several, if not many, successive generations to see gains. From my experience with breeding many sp. of mammals and rodents, when you breed for a particular trait, other traits can (and often do) show undesirable variation that must be dealt with. I think you could conceivably produce an enormous tarantula, but it might have say, a shorter lifespan, be less hardy or have some physical deformity.

To selectively breed anything, you select the specimens w/ the desired trait to the exclusion of other traits. To overcome this in future generations, you outcross, but this slows the progression towards the trait you wish to enhance. With t's it could take a very long time breeding for size. I'd imagine you'd need to breed t's in advanced maturity only to get a grip on the individuals' max size. Quicker would be breeding for increased growth rate; you wouldn't need to wait for size to show, just timeframe to maturity.
 

Vermis

Arachnoknight
Old Timer
Joined
Dec 11, 2005
Messages
214
just a random question that I want to know about, How big were prehistoric inverts/ spiders/ ....tarantulas?
I was going to mention Megarachne servinei (legspan ~50cm), but after a quick google I learned that it's recently found to be a euryptid and not a spider. So the biggest known spiders are ones alive today - Theraphosa and Lasiodora spp. etc.
 

Drachenjager

Arachnoemperor
Old Timer
Joined
Jan 23, 2006
Messages
3,509
I was going to mention Megarachne servinei (legspan ~50cm), but after a quick google I learned that it's recently found to be a euryptid and not a spider. So the biggest known spiders are ones alive today - Theraphosa and Lasiodora spp. etc.
yeah i saw that too and it wasnt long ago that the discovery channel had a show that was talking about megarachne but ... now i guess they wont show it again cause its wrong lol
was entertaining tho
 

ShadowBlade

Planeswalker
Old Timer
Joined
Apr 1, 2006
Messages
2,591
With selective breeding, size could be increased, but it would take several, if not many, successive generations to see gains. From my experience with breeding many sp. of mammals and rodents, when you breed for a particular trait, other traits can (and often do) show undesirable variation that must be dealt with. I think you could conceivably produce an enormous tarantula, but it might have say, a shorter lifespan, be less hardy or have some physical deformity.
Arachnid genetics work a little differently though.

About the whole 'maximum' size thing, it is not likely any theraphosid could live bigger then 15" TOPS. Beyond that, they would literally collapse under their own weight, or die of asphyxiation. Also, notice the molting difficulties of adult T. blondi? Increased size would only make it more difficult.

-Sean
 

omni

Arachnobaron
Joined
Apr 30, 2007
Messages
382
:? yeah, I guess i still have lots to learn about tarantulas- I'm finding many general pet-keeping rules don't apply to T's... they are in a class by themselves. Hey, we can always hope for some type of freak mutant after a nuclear war:)
 

treeweta

Arachnobaron
Old Timer
Joined
Jan 15, 2006
Messages
362
I personally have never seen a photo of a tarantula with a scale which is bigger than 25cm/ just under 10 inches.

That for a blondi may not seem especially large (as they are all that big yes?) but you will notice that most adult blondis you see are about 8.5 inches and seem huge, that extra 1.5 inches makes a huge amount of difference, the carapace and leg thickness increase more in proportion to legspan with each moult, Im guessing that a blondi at 10 inches has almost twice the mass of one at 8.5 inches.

Ive seen one which was supposed to be 11 inches (no evidence though) and it was colossal, the legs were unbelievably thick. By the time a female blondi got to 12 inches the carapace would be getting to 5.5cm+ and im not sure they can get that big. What we need is evidence, the best way is a moult with a ruler next to it. I know so many people who have '10 inch' blondis and they are really about 8 inches, they get to that size quickly, its the difficult moult year after year that gives the giant animals! I have a 12 year old T.apophysis (which i cant access now its in another country) her last moult I saw was 9.25 inches but she had grown noticably, this picture link is of her after that moult so possibly 10 inches.

http://www.arachnoboards.com/ab/gallery/showimage.php?i=1778&c=51


she has since moulted again but until i see her in person i will have no idea of size, maybe with 2 extra growth increments shes got to 10.5, apophysis though do not have the bulk of blondi, not by a long shot, but when i next see her i will get shots of the skin with scale. Personally Id be very suprised (but delighted) if a 12" reliably documented blondi ever shows up, apophysis maybe.
 
Last edited:

ShadowBlade

Planeswalker
Old Timer
Joined
Apr 1, 2006
Messages
2,591
The biggest T I've seen, was a freakin' huge female L. parahybana. I was so close to buying her it wasn't even funny. (the $250 price tag deterred me). This thing was so big, if the store owner told me she was 11" I would have believed him.

-Sean
 

Drachenjager

Arachnoemperor
Old Timer
Joined
Jan 23, 2006
Messages
3,509
:? yeah, I guess i still have lots to learn about tarantulas- I'm finding many general pet-keeping rules don't apply to T's... they are in a class by themselves. Hey, we can always hope for some type of freak mutant after a nuclear war:)
yeah thats the ticket lets nuke the world so we may accidentally get some freak glowing tarantula wiht a Leg span of 16" lol
I dont think so sport lol
 

Drachenjager

Arachnoemperor
Old Timer
Joined
Jan 23, 2006
Messages
3,509
What is the largest T. blondi officially recorded? I am going to guess that one seen in the wild wiht no way to get an accurate measurment would be guessed as much larger than thier real size. so reports of wild blondis of 12+ LS is pretty unreliable with out accurate mesurments. I mean i know i can judge length fairly well up to 24" but, i swear i have seen some 36"+ SHC at lake buchannan....if you know what i mean
 

treeweta

Arachnobaron
Old Timer
Joined
Jan 15, 2006
Messages
362
What is the largest T. blondi officially recorded? I am going to guess that one seen in the wild wiht no way to get an accurate measurment would be guessed as much larger than thier real size. so reports of wild blondis of 12+ LS is pretty unreliable with out accurate mesurments. I mean i know i can judge length fairly well up to 24" but, i swear i have seen some 36"+ SHC at lake buchannan....if you know what i mean
LOl, in my experience peopel always overestimate bug sizes, praying mantis round here are 8 inches long according to the locals!!
 

treeweta

Arachnobaron
Old Timer
Joined
Jan 15, 2006
Messages
362
heres a link to an old article on selective breeding blondis, the largest blondi i ever saw was one of this guys, indeed it could be the animal pictured, no scale but you can see its a very bulky animal even ignoring the oversized abdomen. The 9 inch legspen quoted is probably an underestimate.

http://arachnophiliac.info/burrow/bustard.htm
 
Last edited:
Top