An Aurthurian Myths & Legends book gives the sister of Igraine (Arthur's mother) and mother of St Illtyd as Riengulid. I assume it to be Welsh, simply from how it sounds, but I have no idea what it means (I checked the list already!). A site about St. Illtyd himself/herself (various sources disagree on the gender of this Welsh saint) named the mother as Riengulidia, which sounds like Riengulid Latinized to me, but, if anyone knows or can find out I would greatly appreciate it. Zor spas!
The spider takes hold with her hands, and is in kings' palaces.