The yellow-backed spiny lizard, Sceloporus magister uniformis, is well known from the Mojave Desert, where it is widespread and abundant. It is less well known from Central California. We report on an intensive survey effort conducted in 2024 where we sought out S. m. uniformis across its potential range in the San Joaquin and western Mojave Desert, using visual surveys and scat detection dogs / genotyping from scat. We found S. m. uniformis to be widely but patchily present in the western San Joaquin Valley and associated ranges from the Panoche Hills in the north to the Lokern region in the south. The species was found to be present in the Transverse Ranges to the south of the San Joaquin Valley and abundant in the western Mojave. Preferred habitat was rock outcrops and anthropogenic structure such as riprap in desert washes. Temperature preferences ranged from about 18C to 30C, and the species could be observed March-October whenever the temperature was within these bounds. We present an updated map of its distribution in central California. This large lizard deserves increased attention due to its potential endemism and restriction to the San Joaquin Desert biome.