Harlequin shrimp sex ID?

[colourmop]

i've read many FAQs about harlequin shrimp and how to determind their gender, but none of them have a very clear picture. so if anyone know about harlequin shrimp, could you check for me if the larger one in the picture is a female? note the plate near it's butt have this redish dot on it, while the smaller one dont have it.
p.s. the big 1 being a bully, they use to live together fine :
thanks ^^

 

[xdave]

This is a female. The tip of that leg is blue, on a male it's clear.