Mutations in the gene ABCA4 coding for photoreceptor-specific ATP-binding cassette subfamily A member 4, are responsible for the most common form of inherited macular degeneration known as Stargardt Disease type 1 (STGD1). STGD1 typically declares early in life and leads to severe visual handicap. Abca4 gene deletion mouse models of STGD1 accumulate lipofuscin, a hallmark of the disease, but unlike the human disease show no or only moderate structural changes and no functional decline. Reasoning that the low cone complement of mice (Psammomys obesus), a diurnal rodent containing >30% cones. Compared to control injections of AAV-GFP, treated eyes exhibited extensive and rapid (visible 2 months after injection) retinal degeneration. Non-invasive fundus imaging showed widespread photoreceptor loss, confirmed by optical coherence tomography. Functional recording by single flash and flicker electroretinography showed significant decline in photopic (cone) light responses. Post-mortem real-time PCR, immunohistochemistry and western blotting showed significant decrease of cone-specific (MW cone opsin) but not rod-specific (rhodopsin) markers. Transmission electron microscopy showed large numbers of lipid inclusions in treated but not control retinal pigmented epithelium. Finally, UPLC analysis of whole P. obesus eyes showed the presence of all-trans retinal-dimer, not detected in rod-rich rat eyes. In conclusion, this animal model of STGD1 more accurately reflects human STGD1 and should be valuable for characterizing pathogenic pathways and exploring treatment options.