There was someone asking about this a while back and there was a very nice post with a recipe. But this is what I've found over the past few weeks, having eaten some myself.
Tuna, primarily yellowfin tuna, has been caught for centuries around Tarifa in the Costa de la Luz in Spain using a complicated tuna net trap called an almadraba. The tuna is processed by taking the loins (lomos) and salting and air-drying them like prosciutto/jamon serrano or bresaola. The name for this product is mojama from (according to http://www.vox.es/consultar.html) the Arabic almuxama, the dried. It is made in other parts of Spain, like Alicante, as well and is available in many places as a tapa (and can be purchased online and in Spanish import shops here).
With the Arabic influence, Sicily also makes mojama, called mosciame. It has been made in Sardinia as well and is sometimes used in Ligurian food, especially in the dish Cappon Magro, a fish(apparently Lenten) dish.
Non pc note, it seems that a mojama/mosciame was also prepared in the past of mammalian dolphin meat as well as of tuna (one or the other, you can't mix the meat). This is illegal today although one website shows a very distressing picture of a dolphin skeleton with the thought that the dolphin may have been butchered for black market dolphin mosciame (this was in Sardinia) which, acdg to the site, retailed for about one million Italian lire per kilogram.
By the way, tuna mojama is amazingly delicious, as tasty and interesting as a prosciutto or a bresaola but with hardly any fat (0.2 g of fat per 100 g). I'm amazed it's not more popular.