I don't remember reading that ALL spiders are descended from ungoliant: other Maiar demons took the form of spiders (just as several Maiar Demons took the form of a balrog), just ALOT of spiders where descended from ungoliant.

Ungoliant was never stated as a corrupted Maiar either. In fact Tolkien hinted it was around from before the Valar arrived.
Also I don't remember anywhere in the books that Goblins rode spiders instead of horses. 19:58, 10 March 2008 (UTC)
You are correct. The goblins did not ride the spiders. That concept was present in a video game (The Battle for Middle Earth 2). Thanks! TheGreyPilgrim|Talk|Contribs|Edits 22:16, 10 March 2008 (UTC)
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