According to family tradition, my gr-gr-gr grandfather Salvador Moraga was married to Christina Aros. Aros has been a very difficult name to trace. It seems to appear in Sonora in the early 1800's and is concentrated around Magdalena and Altar. A web search has not indicated that it is found in Spain, so it may be a shortened form of Arostegui.A soccer player in Argentina was named Aros. Argentina seems to be another place where one finds a lot of derivative basque names.
An Arostegui founded the spanish settlement at Ures in the 1700's, but the name dwindled. Horcasitas had many Lopez de Haro families, sometimes abbreviated to Haro and sometimes spelled Haros. Aros could be a variant of this name.
Are there any Aros descendants out there with an opinion about the origin of their name? I would like to hear from you!