This is rather peculiar. Dont think its as simple as male vs female but I could be wrong. Think its a growth impediment

Looking at Peter's photos there is a significant deference in the 2 T's, very odd indeed.

Icarus do you have photos of them?

Hi Peter, your pictures are not of the same species. One is Acanthoscurria geniculata and the other Grammostola rosea.

I got a B boehmei from Visser that he gave to me due to the fact that it barely ate and hadn't molted for a long time, he scared it just died.
It is clearly growing slower than it's brethren, but I think it has to do with being a runt of the litter instead of gender.

There was a very nice article in the BTS Journal (2010, Vol 26, No 1) called-
The World's Oldest Male Spider, Homoeomma sp. blue
Where this species males all matured in about 3,5 years the one took 15 years to mature.

I agree with SynergyZA might be the runt of the litter.

I wouldn't say gender has anything to do with it.

IcarusZulu please keep us posted on the gender of the little runt

Hendrijs wrote: Hi Peter, your pictures are not of the same species. One is Acanthoscurria geniculata and the other Grammostola rosea.

Agree with hindrijs


I got a whole bunch of doubles or some times more of the same species, at it noticeable how some spiders grow faster than the other, all my spiders are kept the exact same way, feed the exact same time heated the same time.

And I see some of them grow faster than the other all the time, I got 2 A. jurenicola one molted out yesterday it was 1cm before molting out, its brother is sitting at 3.5cm.

I got 2 P. reduncus one is sitting at 8cm and the other is still sitting at 4cm.
Not saying that it got anything to do with sex of the species, I have only been able to sex the one and it is a IM (immature male), still waiting for the other one to molt.But this species males are known to mature with in one year.

Same goes for my B. vegans and my B. ablopilosum
They seem to molt at the same time, but they differ in leg span, from a difference of 1 to 3cm.
Most of the B. ablopilosum are females. out of the 7 there are 4 females, the rest I have not sexed yet.