Pit Flyer Spawner

Pit Flyer Spawners are a type of monster seen in Diablo III concept art and gameplay videos. It may be some kind of monster spawner or just a kind of demon, judging by appearance.

Nest?
The Pit Flyer Spawners may play the same role in Diablo III as the Blood Hawk Nest did in Diablo II. The Pit Flyer Spawners could spawn the red bats seen in the Blizzcon '08 Gameplay Video; both monsters are red and bat-like.