These are the new zombies. As Lily the Coyote says, "They're not what you think they are. They're smarter, they're faster, they're organized." The alpha zombie is a strong, sentient zombie that can plan, control other zombies, and piece together armor & clothing. They might even be capable of some level of romantic feelings. Zach Snyder apparently mentioned "Alpha elites," so there's no surprise there's a "queen" zombie, as well as a king, ie Zeus. According to Deborah Snyder, the alphas can communicate non-verbally like a wolfpack. And only Zeus can create other alphas with his bite. The bite of other alphas creates shamblers.