Some go a little bald on the abdorem while others just go off food,
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"Revenge is scared into my soul. Agonizing for its arrival our
wishes become our relief---Sleep where you are equable"
genesis- from 'loveles
Going bald is not a sign of an upcoming moult. If the skin under that bald patch is jet black and shiny then it is going to moult. Spiders normally refuse food for upto a week or more before they moult too. They may also web a "mat" on which they'll moult, or baracade themselves into a hide.