Of the 26 species of reptiles reported to be found on the monument, probably rattlesnakes and white lizards are the most asked about by White Sands visitors.
There are 3 species of rattlesnakes found here; the rare desert massasauga (about 20"), the prairie rattlesnake, and the western diamondback rattlesnake (both may reach 4' or greater). All are poisonous. Even though these snakes live in the desert, they can quickly die if unable to seek protection from the direct rays of the summer sun.
Of the 13 species of lizards reported on the monument, the presence of three that have evolved white or light colored forms that enable them to blend with their gypsum background have interested both laymen and researchers from around the world. These lizards are the bleached earless lizard, the Cowles prairie lizard, and the little striped whiptail lizard. These white lizards may be seen in the interdune flats and along the boardwalk.
Of the three rattlesnakes mentioned above, the prairie is common along the edge of the dunes and in the scrubland adjoining the dunes and the western diamondback is present, but not common. The desert massasauga is rare in the monument. These animals are seldom seen, mostly because they are nocturnal, both to escape the heat and because most of their prey species are active at night.
Of the 9 species listed on the monument checklist (see below), two are most likely to be observed by visitors, primarily because they are common along the park roadways and because they can be quite large. The Sonora gopher snake (often called a bullsnake) and the western coachwhip can reach lengths exceeding 4 feet.
The 13 species of lizards inhabiting the Monument can be best grouped according the the genus to which they belong:
Cnemidophorus (the whiptail lizards)........... 3 species*
Sceloporus (the prairie and spiny lizards).... 3 species*
Phrynosoma (the horned lizards)................ 2 species
Crotaphytus (the collared lizards)............... 2 species
Holbrookia (the earless lizards).................. 2 species*
Uta (the side-blotched lizards).................... 1 species
*Exhibit light coloration