Episode 5.06:

Hajer: Male, Arab, 30s-50s. A very local "doctor" who probably doesn't have a traditional medical degree but has the experience to tackle anything the harsh desert can throw at him. Tough bed-side manner but knows how to get the job done. Must speak Tunisian Arabic.

[Note: It's not clear when the character will appear. It could be in 5.07 instead of 5.06.]