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The origins of felsic low-δ¹⁸O melts (< +5.5‰) are usually attributed to assimilation of high-temperature hydrothermally altered (HTHA) rocks. Very few alkaline (silica-undersaturated and/or peralkaline) examples are known. Here, we classify the Miocene Fataga Group in Gran Canaria, a silica-undersaturated to mildly saturated alkaline volcanic sequence consisting of trachytic to phonolitic extra-caldera ignimbrites and lavas, as a new low-δ¹⁸O felsic locality. We provide new mineral, glass, and bulk geochemical data linked to a well-constrained stratigraphy to assess the processes involved in the magma reservoir that fed the Fataga eruptions. New high-precision single crystal feldspar ⁴⁰Ar/³⁹Ar ages of the study area span 13.931 ± 0.034 Ma to 10.288 ± 0.016 Ma. Fractional crystallization at shallow depths of sanidine/anorthoclase, biotite, augite/diopside, titanite, ilmenite, and titanomagnetite is the …