Lamuire
A lord once defeated in combat by Gawain in Heinrich von dem Türlin’s Diu Crône.
When he died, his daughters, Amurfina and Sgoidamur, vied for a magic bridle which gave the owner the rights to Serre. Gawain eventually settled the matter in Sgoidamur’s favor, though he married Amurfina.
H. Sparnaay notes that the corresponding character in Chrétien de Troyes’s Yvain is called ‘li sire de la Noire Espine’, or the Lord of the Black Thorn.
See also
Daughters of the Lord of Noire Espine | The Legend of King Arthur
Source
Diu Crône | Heinrich von dem Türlin, c. 1230