it is normally really easy to sex G. Rosea. if you look on the front two legs, not the palps but the legs you will see hooks if it is male and lack there of if it is a female. at the size of your T if it is male it should have well developed tibial hooks. i do not know enough about sexing to sex it by looking at the ventral side. but if i was to take an educated guess i would say female, judging by the slit at the base of the abdomen. someone please tell me if my assumption is correct or not, for zebadee's sake.