Great Basin Naturalist


Widespread karyotypic sampling in the lizard Sceloporus graciosus Baird & Girard has confirmed previous reports of chromosomal monotypy. Most individuals throughout the range have a diploid karyotype of 2N = 30 consisting of 12 biarmed macrochromosomes and 18 microchromosomes. A single female karyotyped from the vicinity of Riverside, California, was unmistakably triploid, showing 3N = 45 with 18 macrochromosomes and 27 microchromosomes. This female appeared phenotypically normal but appeared reproductively incompetent. A male from Zion National Park, Utah, showed an extra bivalent in some diakinesis arrays, which apparently represents a supernumerary chromosome.