Acromantula

From Hpwiki

An Acromantula is a monstrous spider with eight eyes and a legspan of up to fifteen feet. Their native territory is the dense jungles of Borneo. Acromantulas are capable of human speech, and their intelligence is close to the human range. It is theoried that Acromantulas are wizard-bred. These beasts are untrainable and dangerous to humans of any kind. They fear, along with regular spiders, the basilisk above any living thing.

Rubeus Hagrid has raised one of the beasts (Aragog) while at school, later found a wife for him, and thus founded a colony of Acromantulas in the Forbidden Forest. Also, an Acromantula was stationed in the center of the Triwizard Tournament maze. Acromantula's are Ron's biggest fear, as seen by how the Boggart transforms into one when he faces it.