Atyopsis gabonensis?

I just bought 2 of these, labeled 'fanshrimp.' They are dark-blue grey, the bigger one being darker than the smaller one. I thought they were more 'woodlike' in appearance. IE singapore woodshrimp.
I've googled and have come up with: Fanshrimp, woodshrimp, vampire shrimp. I think the are Cameroon shrimp by appearance.

Anyone know what I've got? How big to expect? They are about an inch and the other half inch or so.

They are Cameroon shrimp. Yup. They get to be 6 inches or so. So now my Asian tank is perfurpled :duh: I thought they were Asian filter shrimp, oh well.