Sexing Porcelain Anemone Crab
 

Is this crab male or female?

http://farm8.staticflickr.com/7158/6...7e33e092_b.jpg

http://farm8.staticflickr.com/7026/6...e9eb6d27_b.jpg

I understand male crabs in general have a triangular plate while females are rounded. With the naked eye I cannot see any triangular bits but in this photo of his/her molted shell I can a triangle - though only after zooming in, cropping and boosting the clarity the max amount.

I would say, male......

Errr... I was going to say male too but the more I look at it I think it's a female. The characteristic carapace section looks too broad to be male. Then again, I haven't sexed many porcelains.

I'm with Steve looks female I think the section is to broad males are supposedto be narrow not just pointed BUT I'm going off my knowledge of red rocks n dungeoness crabs lol much diff

Pretty sure porcelains are actually more related to shrimp, they just imitate the look of a crab. You can tell when they try to escape as the under flap is actually a tail.

I figured that bottom piece detached into a flap (tail) only when the crab molted. I'll look at shrimp sexing info.

So it seems the best way to determine sex is to buy several and see if any pair up. Are the opposite sex fairly similar in looks? I've seen porcelains for sale with different sized spots and different color spots. How can I best be sure to get the same species?