Phrynosoma hernandesi

Phrynosoma ornatissimum is recognized as a species separate from P. hernandesi by Nicholson (2025) based on the works of Montanucci (2015) and Leaché et al. (2021). Leaché et al. (2021) inferred three main populations within P. hernandesi based on phylogenetic and demographic analyses of RADseq SNP data. Although Leaché et al. (2021) did not recognize those three populations taxonomically, they largely correspond to taxa recognized by Montanucci (2015) and are subsequently considered subspecies by Nicholson (2025). The three subspecies of P. hernandesi are: 1) P. h. hernandesi (southern population, consisting of P. h. hernandesi Girard, 1858 plus P. bauri Montanucci, 2015 plus P. diminutum Montanucci, 2015); 2) P. h. brevirostris (northern population, P. brevirostris Girard, 1858); and 3) P. h. ornatum (western population, retains the name from Girard, 1858). Hoza et al. (2023) provided additional evidence that P. diminutum is not a separate species from P. hernandesi and is part of the southern population of that species (i.e., subspecies hernandesi).

This species is widespread in southwestern Canada, the western U.S., and adjacent extreme northern México. There do not appear to be any rangewide threats, but this species has experienced some habitat loss and degradation.

This species is found in southwestern Canada, the western United States, and adjacent northern México. The range includes southern Alberta and southern Saskatchewan in Canada; eastern Montana, the western Dakotas, Wyoming, western Nebraska, southwestern Oregon, southeastern Idaho, northeastern Nevada, much of Utah, much of Colorado, northwestern and eastern Arizona, northern and western New Mexico, and western Texas in the U.S.; and northeastern Sonora and northwestern Chihuahua in México (Leaché et al. 2021, Hoza et al. 2023).


Populations in central and southern New Mexico and extreme western Texas that were previously considered part of this species are now attributed to P. ornatissimum ornatissimum and Mexican populations that were previously considered part of this species in western and central Chihuahua, eastern Durango, and northwestern Zacatecas are now attributed to P. ornatissimum brachycercum (Leaché et al. 2021).

This species is represented by very many occurrences that are well-distributed throughout the wide range (Degenhardt et al. 1996, Hammerson 1999, Werner et al. 2004).

Habitat loss and degradation (e.g., urbanization and intensive cultivation, conversion of native shrubland to dense grass) have caused local declines, but the species appears to face no major threats over most of the vast range (Olson 2009).