Odd white 'spot' on G. pulchripes

[KoriTamashii]

So I was feeding my G. pulchripes, and I noticed this on her:

I gently did my best to inspect it... It didn't seem squishy, and it didn't move or anything.

Any thoughts?

 

[Cirith Ungol]

Ligament. You'll find it on the leg joints too.

 

[KoriTamashii]

Ligament. You'll find it on the leg joints too.

...Really? Oh, wow. Now I feel like a moron