Thanks so much to SnitchSeeker for letting me know that Alecto Carrow has been cast for Harry Potter and the Half-Blood Prince.  I have updated the cast list page for HBP, so you can check it out and see who is playing who in the movie!

Suzanne Toase has been listed to play Death Eater Alecto Carrow, sister of Amycus Carrow (being played by actor Ralph Ineson)

You can see a picture of her HERE.