Who is The Hive Queen from Xenocide and what is their importance?

Somewhat resembling a large queen ant, the hive queen is so much more than an overgrown insect which Ender comes to appreciate while both battling and communicating with her during his war against the buggers. Both Ender and the hive queen have a great deal of difficulty understanding one another given their radical differences.

Following the near total annihilation of buggers (or formics) during the last war with humans, the hive queen was the only remaining bugger alive. After sorting out the numerous misunderstandings that existed between buggers and humans with Ender, he rescues her with the pledge to keep her existence a secret until he can find a safe planet for her to reestablish the buggers as a species. Once Ender lands on Lusitania, he and the hive queen agree that with the piggies' permission, the planet would be quite suitable for her to begin her work.