Moth, ocifant and I had real trouble finding it, despite excellent map reading skills, a comprehensive guidebook with diagram and a GPS! After 30 or 40 mins of scouting around, we DID find it. But it wasn't easy.

My guess is that it's Iron Age and was a structure not related to a fogou. Because of the surrounding field walls, and the way the hut is built into these, I doubt completely whether it ever had a earthen mound covering it. No evidence to substantiate this, mind!
J
x