By Anisa Ismail
Geographic Range
Eastern collared lizards are found in areas between Kansas to northeastern Mexico, primarily in the central plains region, hilly or canyon lands which make up this particular part of the United States. In Texas, this species is found in the central to western regions (Bartlett and Bartlett, 1999).
Biogeographic Regions:
nearctic 
(native ); neotropical (native ).
Habitat
These lizards are found in a variety of habitats, ranging from arid areas with large rocks which are good for basking to hardwood forest regions. More frequently, however, they are found in hilly regions. (Bartlett and Bartlett 1999).
Terrestrial Biomes:
desert or dune ; savanna or grassland ; forest .
Physical Description
These are relatively large lizards, with slender necks, large heads and long tails. There is a definite dimorphism in this species; males are larger and are often very brightly colored with yellow and orange bodies. (Behler 1979)
The most noticeable characteristics of these lizards are found in the two black collars that run from the arms to the neck of the animal. Furthermore, there are usually six dark cross bands which run across the lizard's back (Dundee and Rossman 1989).
The bodies are usually covered with small white spots. Also, the scales on the lizard's body are granular, while the tail scales appear to be slightly larger. (Behler, 1979).
Some key physical features:
ectothermic ; bilateral symmetry .
Reproduction
These lizards, like most other lizard speciess, are oviparous. They lay between 2-11 eggs in each clutch every yera. Under normal circumstances, breeding begins in May and continues through June. The eggs are ordinarily laid during July. In order to protect the eggs from predators, the lizards will bury them in loose sand and beneath the stones that they usually bask on (Bockstanz, 1998).
Key reproductive features:
gonochoric/gonochoristic/dioecious (sexes separate).
Behavior
Eastern collared lizards are diurnal, but remain wary of strangers who might get too close to them. While they will most often run in the presence of danger, they sometimes become quite aggressive and feisty (Baird and Timanus 1998).
When fleeing, the lizard will lift its body and tail, and run on its hind legs. The lizards will hid under rocks or trees nearby until they feel safe to come out again.
They also prefer limestone rocks and ledges on which to bask for thermoregulation. This gives them the perfect vantage from which to observe any threatening intruders (Firth, 1980).
Key behaviors:
motile .
Food Habits
The eastern collared lizard is an active predator. It feeds on a variety of arthropods and small lizards. While food sources vary, these lizards seem to prefer large grasshoppers for nutrition. In addition, spiders, moths, and beetles are also eaten. When the lizard preys on other lizards, it will kill them by crushing their skulls. It must be noted that while these lizards were previously thought to be very cannibalistic, they are now thought to be less so, only killing other conspecifics when necessary (Sugarman, 1988).
Economic Importance for Humans: Positive
The lizards help to stabilize the grasshopper, beetle, and moth populations by preying on them (Behler 1979).
Conservation Status
IUCN Red List: [link]:
Not Evaluated.
US Federal List: [link]:
No special status.
CITES: [link]:
No special status.
No special status at the present time. They are fairly well distributed. However, they might not often be seen because of their nervous nature (Bartlett and Bartlett 1999).
Other Comments
These lizards are unlike most in that they cannot regenerate their tails. Furthermore, there are few differences between the eastern collared lizard and its relative, the western collared lizard. Apart from geographic differences, it is often very difficult to distinguish between the two subspecies (Bartlett and Bartlett 1999).
For More Information
Find Crotaphytus collaris collaris information at
Contributors
Anisa Ismail (author), Southwestern University.
Stephanie Fabritius (editor), Southwestern University.
