a) the dorsal extension
b) the tube is part-down, and although I know you cant tell from a partly-down tube outside of breeding, this one really does look like the tip of a male tube. It looks too long to be the corner of a female tube
c) another forum (EACG) has confirmed my suspicion that not every individual is cut-and-dried easy to tell from the gill-spots(somebody raised fry from two spotless fish?)
Btw, the fish is nearly 8"TL.




Thank you for your help


