It's a male. I stole the pic and drew on it. Click here. The blue line indicates where the spermathecae would be if it would be a female, in this case it would look like a "flap", but it's missing here (very visible on this B. emilia exuviae - click here). The red line shows what is probably the area of epiandrous fusillae - specialised spinnerets used in making the sperm web, only males have these, they noticeable from the outside, especially in older juveniles/adults.