Sceloporus cowlesi
Silhouette: SeismicShrimp · PhyloPic
In 3 days ~60% in a week ~90%
The southwestern fence lizard (Sceloporus cowlesi), also known as Cowles' prairie lizard, the White Sands prairie lizard or the White Sands swift, is species of spiny lizard in the family Iguanidae. The species is native to the Chihuahuan Desert of the south-western United States and north-central Mexico. Originally described in 1956 as Sceloporus undulatus cowlesi, a subspecies of the eastern fence lizard, subsequent DNA studies elevated the southwestern fence lizard to species status.
The following cladogram is based on Leaché and Reeder, 2002, and shows the relationship of Sceloporus cowlesi to other species in the "Sceloporus undulatus group". The specific name, cowlesi, is in honor of American herpetologist Raymond Bridgman Cowles. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Guadalupe Mountains National Park | 🇺🇸 United States | |
| 2 | Big Bend National Park | 🇺🇸 United States | |
| 3 | Saguaro National Park | 🇺🇸 United States |
Possible
About 20% of wildlife watchers report a Southwestern Fence Lizard sighting in Big Bend National Park on a given day, based on 77 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 11th most-seen of the 48 reptiles we can rate there. Over three days the chance rises to about 60%, and over a week to about 90%, if each day is a fresh chance.
August and September
In those months about 40% of wildlife watchers report a Southwestern Fence Lizard in Big Bend National Park on a given day, against under 5% in December and January, the lowest months. Those are among Big Bend National Park's wettest months, with about 50 mm of rain a month against 10 mm in April.
Between 9 am and noon
Across all the parks we cover, that three-hour window holds the most Southwestern Fence Lizard sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
2nd of 3
Of the 3 parks where we can rate Southwestern Fence Lizard sightings, Big Bend National Park ranks 2nd at about 20%. The best odds are in Guadalupe Mountains National Park (United States, about 70%).
Same genus: Sceloporus
The closest relatives of the Southwestern Fence Lizard that you can see in Big Bend National Park (genus Sceloporus, Spiny Lizards) are Canyon Lizard (about 30%), Crevice Spiny Lizard (about 30%) and Twin-spotted Spiny Lizard (about 20%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Southwestern Fence Lizard is recorded against all the reptiles logged in Big Bend National Park (77 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
