It had a strong bitter lemon taste with hints of a madarin smell. The large majority of fruit in the area are sour orange, but most of the trees were fruitless and I could not make an ID.
It's probably a sour orange x mandarin then, where the mandarin had zipper skin. Sometimes sour oranges can have that type of exterior that looks like a lemon but one would typically not expect a hybrid with mandarin to be so yellow.
Common lemons originally came from hybridization between citron and sour orange, which may explain why the fruit looks so reminiscent of a lemon.
I recently had the opportunity to try sour orange for the first time and it was very fragrant, the fragrance was comparable to lemon. Part of the smell is comparable to orange blossoms and pomelo, but also with the tanginess of orange peel. The bitterness is not terrible; I can enjoy eating one or two of the little fruits out of hand, although they are not very sweet and don't have a huge amount of flavor, though what subtle flavor they do seem to have is good, apart from the slight amount of bitterness.