Go google a bunch of Grammostola pictures and you will see that some shows the white spot more prominent and some does not, there are even some that shows a slightly darker spot where the carapace and abdomen connects.

So nothing to worry about.

Thanx guys

As I said I wasn't too concerned but I have never noticed this before. Check on her this morning and she is doing fine. But she needs an enclosure change. She left all her cricket leftovers inside her borrow and it is now quite a mess. Obviously not very big on house keeping. Will sort her out over the weekend as I have a couple of T's that need to be rehoused.