According to
Daeron I, who recorded his wars in Dorne, there were three sorts of Dornishmen.
- 'Salted' Dornishmen , who lived along the coastlines, which were generally thin and dark, with olive skin and black hair.
- 'Sandy' Dornishmen, who lived in the deserts and river valleys, with dark brown skin and tended to wear long, bright scarfs around their helms to keep the sun off.
- 'Stony' Dornishmen, who lived in the Red Mountains, large and fair, they still contained the blood of the Andals and the First Men, usually with blond or brown hair and freckles.
The salty Dornishmen have the most Rhoynish blood, the stony Dornishmen the least.
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So clearly depending on the character, Dornish can include Mediterranean looks, Indian/Arabic looks and (for eg the Daynes) blue eyed, blond Europeans.
Arianne- has olive skin (also not pure Dornish)
Doran- looks like his son
Oberyn- his skin colour is not remarked upon, only his hair and eyes which are black
Quentyn- his skin colour is not remarked upon