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9- Side-blotched lizard

Uta genus 

From Wikipedia, the free encyclopedia


Side-blotched lizards are lizards of the genus Uta. They are some of the most abundant and commonly observed lizards in the deserts of western North America. Their cycle among three colorized breeding patterns has achieved notoriety[1] and is best described in the common side-blotched lizard. They commonly grow to six inches including the tail, with the males normally being the larger sex. Males often have bright throat colors.


These lizards are prey for many desert species. Snakes, larger lizards, and birds all make formidable predators to side-blotched lizards. Larger lizard species, such as collared, leopard, and spiny lizards, and roadrunners are the main predators. In turn, the side-blotched lizards eat arthropods, such as insects, spiders, and occasionally scorpions.


As a result of their high predation rate, these lizards are very prolific breeders. From April to June they breed, with the young emerging as early as late May. These inch-long young appear all through the summer, and into September.


The diploid chromosome number in most if not all species is 34, consisting of 12 macro- and 22 microchromosomes.[2]

Side-blotched lizards 

Male common side-blotched lizard
Uta stansburiana

Scientific classification :







Baird & Girard, 1852

Sex :


Side-blotched lizards are notable for having the highest number of distinct male and female morphs or "genders" within a species: three male and two female. Reproductively the males have testes and the females have ovaries. However they show a diversity of behaviors associated with reproduction, which are often referred to as "alternative reproductive tactics".[3]


Orange-throated males are "ultra-dominant, high testosterone", who establish large territories and control areas that contain multiple females.

Yellow stripe-throated males ("sneakers") do not defend a territory, but cluster on the fringes of orange-throated lizard territories, and mate with the females on those territories while the orange-throat is absent, as the territory to defend is large. Blue-throated males are less aggressive and guard only one female; they can fend off the yellow stripe-throated males but cannot withstand attacks by orange-throated males. Orange-throated females lay many small eggs and are very territorial. Yellow-throated females lay fewer, larger eggs, and are more tolerant of each other.[4]  


This is called the rock paper scissors effect.,[5] borrowed from the name of the playground game, because the outcome of the mating success shows that one morph of the lizard takes advantage over another but not over the third.[6]


The orange and blue-throated males can sometimes be seen approaching a human "intruder". One speculation is that he could be giving the female(s) a chance to escape, but whether he is defending the female has not been documented. Another speculation is that he is highly motivated to engage whenever he sees movement on his territory, which he may be interpreting as a possible intruding male, or another female.

Systematics :


 The systematics and phylogeny of the side-blotched lizards is very confusing, with many local forms and morphs having been described as full species.[7] Following the 1997 review of Upton & Murphy which included new data from mtDNA cytochrome b and ATPase 6 sequences, the following species can be recognized pending further research:


  • Eastern side-blotched lizard, U. stejnegeri - formerly included in U. stansburiana

  • San Pedro Martir side-blotched lizard, U. palmeri

  • Angel de la Guarda side-blotched lizard (undescribed species, formerly included in U. stansburiana)

  • Salsipuedes side-blotched lizard, U. antiqua - formerly included in U. stansburiana

  • Santa Catalina side-blotched lizard, U. squamata - sometimes included in U. stansburiana

  • San Esteban side-blotched lizard (undescribed species, formerly included in U. stansburiana)

  • San Pedro Nolasco side-blotched lizard, U. nolascensis

  • Common side-blotched lizard, U. stansburiana

  • Western side-blotched lizard, U. (stansburiana) elegans

  • Nevada side-blotched lizard, U. (stansburiana) nevadensis

  • Northern side-blotched lizard, U. (stansburiana) stansburiana

  • Eastern side-blotched lizard, U. (stansburiana) stejnegeri

  • Plateau side-blotched lizard, U. (stansburiana) uniformis

  • Enchanted side-blotched lizard, U. encantadae - possibly belongs into U. stansburiana

  • El Muerto side-blotched lizard, U. lowei - possibly belongs into U. stansburiana

  • Swollen-nosed side-blotched lizard, U. tumidarostra - possibly belongs into U. stansburiana

  • Socorro side-blotched lizard, U. auriculata - possibly belongs into U. stansburiana

  • Clarion side-blotched lizard, U. clarionensis - possibly belongs into U. stansburiana

  • Ornate side-blotched lizard, U. mannophora - possibly belongs into U. stansburiana

Uta stellata and U. concinna are now usually considered subspecies of U. stansburiana. U. encantadae, U. lowei, and U. tumidarostra might be subspecies of a distinct species (Las Encantadas side-blotched lizard), instead. Similarly, U. auriculata and U. clarionensis might be subspecies of a single species, the Revillagigedo side-blotched lizard.

For the external links , refrences  click here to read the full wikipedia article 

Video : 

These Lizards Have Been Playing Rock-Paper-Scissors for 15 Million Years | Deep Look 

General care articles :


1- SideBlotched Lizards :

courtesy to :

Sideblotched Lizards:


(Uta stanburiana)
Baird and Girard, 1852.
Uta stansburiana & subspecies.
1. Common sideblotched lizard. (U.s. stansburiana)
Found; Nevada, Utah, California, Arizona.
2. California Sideblotched lizard (U.s. elegans)
Found; California, Arizoona, Mexico.
3. Nevada “Northern” Sideblotched lizard. (U. s. nevadensis)
Found: Nevada, Oregon,Washington, Idaho.
4. Desert Sideblotched Lizard. (U.s. stejneegeri)
Found: New Mexico, Texas and Mexico,
Possibly also found in Utah and Colorado.
5. Colorado Sideblotched Lizard. (U.s. uniformis)
Found; Colorado, New Mexico, Arizona, Utah




(Uta stanburiana) Baird and Girard, 1852. 

General Information:



Male Sideblotched lizards are slightly larger than females and can 
measure from 1-4” when measured from the tip of the nose to the vent
slit just before the tail begins. Scientists call this method of 
measurement S.V.L. (Snout,Vent, length.)
Male Sideblotched lizards are more colorful than females.
This is called sexual dimorphism. Males may also exibit a high degree
of orange pigmentation when breeding. Females have striking blotched
or white striped patterns that are also very attractive but lack the bright
coloration of the males. The pattern of the females varies from spots
to stripes and blends brown, white and grey speckles.
Sideblotched lizards have A black to blue “blotch” that is found on the
chest directly behind the front legs.
This blotch is the deciding charicturistic in defining the species.
Males also have yellow and blue blotches and speckles on their back as well. 
Interesting enough, Patternless Sideblotched lizards are not uncommon
especially around sand dunes, and dry lake beds.
Sideblotched lizards are generally the most common lizards,
to be seen by people who are hiking in the desert.
The Sideblotched lizard seem’s to like to “observe” people often times
seeming to wonder what we are... 
Sideblotched lizards are very common and are found through out
most of the desert regons, from the Pacific coast and found on sand
dunes moving through all of Nevada, in parts on Utah, Oregon and
Washington extending down to Texas and into Mexico. 
Sideblotched lizards can be found in open deserts, campgrounds
and vacant desert lots. Sideblotched lizards do not seem to prefere
one substrate over another and can be found from sand dunes to
desert grasslands. Occuring on the sides of desert hills and small
mountians to 6,500 feet. Sideblotched lizards are very adaptable.
Of all of the Desert lizards, the Sideblotched lizard can be found
through out the year on warm days, even in colder months.
Sideblotched lizards can be found around the bases of small desert
shrubs and also in rock piles and rocky hillsides.
When enclontered they may allow an observer to go get within a few
inches before darting under any available hide shelter.
They are dirunal, and are rarely if ever, encluntered at night.

The role of the Sideblotched Lizard in the Wild:


Sideblotched lizards are commonly the food item for many of the
deserts prediators including; Snakes, Road runners, small hawks,
Collard and Leopard lizards. Rodents may also eat them.
Sideblotched lizards are very succesful by being so enviromentally
adaptive and by producing several clutches of eggs each season thus
insuring the continued succces of the species.


Captive Care & Encloures:


Male Sideblotched lizards are aggressive and should not be housed
together. In nature a male sideblotched lizard may have a terratory
of 150’ (feet). Females are allowed inside this 150 foot square but
a male will rush to defend its “block” from any other male intruders.
In captivity, one male and several females makes a nice colony.
An enclosure of at least 36” long should be used to house them.
As mentioned decoration and substrate are not as important as
providing a shelter. Sideblotched lizards are lively little lizards that
seem to constantly dart about nerviously if not given a small cave to
hide in. Using sand as a substrate also works nice for them as it 
provides them with the oppertunity to bury into it each nite.
Sideblotched lizards will “bob” heads and seem to have a 
communication and terratory system that is enjoyible to watch in the


Sideblotched lizards are found in the desert and they require higher
temperatures than many other captive reptiles.
An ideal Sideblotched setup would be a 30 to 55 gallon aquarium
or like sized wooden encloure. If you use wood to construct your 
enclosure, make sure that vent holes are present and that care has
been taken to properly seal all small cracks or your lizards will escape.
A screen cover of sunscreen or screen-door screen should be used to
cover the top of the enclosure. Remember to use a mesh size that
they cannot slip through.


Substrate :


Should reflect native location, sand, small pebbles or crushed lava
or pumace make nice substrate. For decoration , Small succulants
or plastic “fake” cactus may also be used.
Sideblotched lizards have been housed on newspaper and turf carpet.
Common thought is that you should provide an enclosure that is as
“natural” as possible, your lizards will be much happier and will live
longer. Sand makes an attractive, natural display.
Providing a shelter or small cave is important as sideblotched lizards
need a retreat from prying human eyes, and two shelters should be
considered. Rocks may also be used to decorate and sideblotched 
lizards will perch on them especially if located under the spot lamp.
Be sure that all of the rocks are anchored or touching the bottom, so
that the rocks will not fall on top of or crush your lizards should
they dig around them or climb between them.


Lighting :


The enclosure should be lite by at least a 30” *full spectrum light.
and two are better than one.
This is not the same as a tropical fish lite or common shop bulb.
This light should be on a timer and set to come on at 6 am and go off
at 6 pm in the summer and, be reduced by a few hours in the winter.


spot lamps (clip on lights): 


A spot lamp with a 40 to 60 watt incandesent bulb should be placed
over the side of the encloure above the heat pad and should priovide
a “hot” spot of at least 100 f., during the day and should also be on
the timer, and go OFF at night allowing the temperature to drop.




Should be provided by the use of an “under the tank heater”(U.T.H.)
or heating pad, This pad should be placed so that it it not pinched by
the tank or wooden frame. Heating pads and heaters work best if some
air can circulate around them, providing convection. 
The heating pad should be located on the “hot” side of the encloure
and should be located below the spot lamp. A rock or perching object
should be placed over this spot so that the heat from the pad “radiates”.

Hot and Cool sides of the Enclosure: 


Lizards need to be able to regulate their body temperature, they will
do this by moving from the hot to the cool side of the enclosure.
Care must be taken so that lizards can move away from the “hot” side
of the encloure. If the enclosure is too small the lizards may overheat
and die. The “cool” side of the enclosure should be near 80 f during
the day and can drop to 70 f at night.
The “hot” side temperature will be reduced a bit as the spot light goes
out at nite, but will remain warmer due to the heating pad under the
tank. A hide shelter should be located on both the “hot” and “cool”
sides of the encloure. Remember, because of the heat rising from 
under the tank on the “hot” side, a small air hole must be drilled in
the shelter on the hot side to allow trapped hot air to escape,
otherwise the hide shelter can become a death trap for your lizards.




Sideblotched lizards will eat any small insect that they can swallow.
One report claims that they may also eat other smaller lizards,
this is not likely as they tend to be the smallest lizards in their ecosystems.
In the wild, they eat small spiders, ticks, grasshoppers and beetles.
In captivity they eagerly accecpt two week old crickets, fruit flies,
small mealworms and mealworm beetles. Waxworm months are also relished.
Sideblotched lizards will also eat an occasional small honey pot or
black ant.
I have noted that they run from red harvester ants and fire ants.
A Great method for feeding small crickets and mealworms to your
lizards, is to place a small clear tupperware dish submurged into the
substrate. Make sure that the lizards can see down into it.
It is important that you plcae a small piece of apple or orange for
your insects to eat and drink while in the food dish, so that they do
not die before they are consumed by your lizards.
You should also be feeding “dusted” insects.
Some vitamins can be sprinkled into the food dish, but be careful
not to put too much on them, otherwise the insects will die before
being consumed by your lizards.




A common term used to describe “coating” prey items with vitamins
or medications so that when consumed by reptiles they receive the
intended dose of medications,vitamins and/or minerals.
A simple method for “dusting” is to place the food insect(s) into
a plastic baggie or small plastic container. Place a small amount of a
good quality reptile vitamin/mineral suppliment into the baggie or
container and shake. Once the food is coated with the vitains simply
release them into the encloure. Be sure to only coat a few insects at
a time, the reason for this is that the vitamins will kill the insects and
if your animals don’t eat all of them they may all die before you can
feed them to your animals.


Water :


Should be provided in a low rock type water dish, water need not be
moving to attract them to it.
* Clean water should be provided daily.


*(note: Some keepers of Desert reptiles advise against putting a water dish into
desert encloures as it may cause high humidity that might lead to shedding
problems. I have never found this to be the case. 


Captive Longevity & Reproduction:


In captivity, Sideblotched lizards may live for 5 or more years.
Breeding can be acomplished by allowing a winter hibernation to occur.
After a cooling period, when the male and females are placed back
into the enclosure and temperatures are GRADUALLY retuned to
normal, breeding can occur.
Actual copluation is usually proceeded by courtship involving;
head bob’s and push up displays, licking of the females ventral area
as well as licking the back of the females neck followed by the male
grasping the back of the females neck in his mouth. Their tails and 
ventral areas intwine in typical lizard breeding fasion.
*Male sideblotched lizards will not attack and persue females to breed,
there for breeding occurs after hibernation and by the color and sight
of females within the Males terratory.
*(Ferguson 1966)


If the female(s) are submissive and allow the male’s advances,
breeding will surely follow.
Breeding may occur in any warmer months but is most common in
early summer. Females can store sperm and thus may be able to
produce more than one clutch without being mated each time.
Up to seven clutches may be laid during the year. Eggs should be placed
in virmiculite in a deli style cup placed in an incubatior at 85 f.
Gestation takes 50 -60 days at 85f.



Side blotched lizards make great companions for Banded geckos
and Horned lizards also for some smaller spiny’s and swifts.
Don’t forget that because they are small, larger lizards can and
will prey on them!
Do not keep them with large Spiny’s, Leopard or Collard lizards.
Do not house more than one male together as aggression and fighting
will occur, also sometimes a larger male may keep a smaller male
from eating.


Captive v.s Wild Collected:


Consider buying Sideblotched lizards when possible from repitible
dealers; who list them for sale. But, keep in mind that they are many
times not listed on dealers lists except as “feeder” lizards.
You may have to inquire about them as they are often collected as
“feeders” for snakes and many times they are in poor shape when purchased. 
Collection of a few specimens may be better than purchasing them.
Weigh the options. Years ago many herpetoculturists collected side
blotched lizards by burying a five gallon bucket to the rim and 
placing a old board or simular item over it to conceil it.
The lizard collector would come back the next moring to empty 
the bucket of all of the small lizards that would fall in. Care must be
taken with this type of trap as spiders and scorpions also fall into
these buckets and may bite or sting when you reach into the bucket.
Do not use a bucket trap unless you plan to check the bucket everyday
until you have collected a few lizards. You should then remove the
bucket and rebury the hole.
You should never abandon the bucket trap as any captured lizards
will surly die from exposure to the heat building up within the bucket,
as well as to preditors like snakes and even dogs and cats that may 
hear the little lizards scratching for freedom at the sides of the bucket.


Collection and the Law:


Sideblotched lizards may be field collected in most western states.
However, laws are constantly changing and a person should always
“Check” BEFORE you “Collect”! 
Even in restricted states, some will allow you to collect a few for
your personal collection. A fish or wildlife tag or liscence may be
required for a small fee.


My captive Observations:


My captive observations with this species have been positive.
With the exception, They are very small and do NOT seem to enjoy
handling at all.
I find that cleaning the encosure is best done by moving them to a
holding bucket, otherwise they dart around in a mad attempt to
allude the hand of the keeper. I have housed these small lizards
with a variety of other desert species including Horned lizards and
Banded geckos. 
The Sideblotched lizards are active lizards that eat readily in
captivity, drink freely and seem to not mind human observance.
They seldom scratch at the walls as if begging for release as some
species do, instead the males establish a terratory and can be
observed in a variety of activities. 
Sideblotched lizards enjoy sunning on key perch positions, moving
about searching for small crickets, especially in early morning and
late afternoon and communicating by head bobbing and doing lizard
push-ups. The Sideblotched lizards have proven to be very interesting
lizards, well worth keeping as pets.

2- How to Take Care of a Side-Blotched Lizard :

courtesy to :

By Talmadge Walker

eHow Contributor



The side-blotched lizard (Uta stansburiana) is a small reptile that lives in the American Southwest and northern Mexico. The adult lizard may grow to about 6 inches from the tip of the snout to the end of the tail. It is brownish gray, with a dark blotch on each side behind the foreleg. The side-blotched lizard is diurnal, and in some areas is active the entire year. Its small size and dark coloration allow the side-blotched lizard to warm up quickly, so it can become active sooner than many other reptiles. The side-blotched lizard eats insects and other small arthropods, and is in turn eaten by snakes and birds. Most hatchlings do not live to adulthood, and most adults die in the first year. The side-blotched lizard is such a prolific breeder, however, that it is not on any endangered list. Although side-blotched lizards are very territorial, they are easy to care for as pets.

The side-blotched lizard is easy to care for. (Image: Jupiterimages/Goodshoot/Getty Images)  

Things You'll Need :



-Rocks and branches

-Reptile vitamin and calcium supplements

-Heat lamp

-Crickets, mealworms

House the side-blotched lizard in an aquarium with sand up to 3 inches deep. This lizard is a desert-dwelling creature, and likes to bury itself in sand at night. Provide branches and rocks for climbing, hiding and basking. Because the males are territorial and will fight, it’s best to keep only one male with several females. Several of the lizards can be kept in a 10-gallon tank.


Maintain a temperature of between 75 and 100 degrees Fahrenheit inside the aquarium. A heat lamp and heating pad are useful for simulating a desert environment. Provide 10 to 12 hours of light for the side-blotched lizard. Direct sunlight is best. If mating occurs, incubate the eggs at about 83 degrees Fahrenheit.


Feed the lizards small insects and larvae. Crickets and mealworms are fine, and are readily available from most pet stores. If you catch your own insects, make sure they are free from pesticides. Give the lizards vitamin and calcium supplements two or three time a week. Young lizards should get daily supplements. The side-blotched lizard gets its water from food, so a water bowl is not necessary.

3- Side-blotched Lizard

courtesy to :

Scientific Name :

Uta Stansburinia


Introduction :


The interesting and unique side-blotched lizard is found on both Anacapa and Santa Cruz islands in the national park, as well on the southern Channel Islands of Catalina and San Clemente. It is a smallish lizard with novel mating behaviors that have been documented in recent studies. Although it is a common and widespread species on the mainland, it nevertheless has an important niche in the park's ecosystem.


Quick and Cool Facts :


  • The specific epithet, stansburiana, is in honor of Captain Howard Stansbury of the United States Corps of Topographical Engineers, who collected the first specimens while leading the 1849-1851 expedition to explore and survey the Great Salt Lake of Utah. Uta is a reference to the state of Utah.

  • Different color morphs, or types, occur in males of this species. Males can have yellow, orange or blue throats, each color indicative of a respective, unique mating strategy.

  • Recent research on the different-colored males has revealed evidence of cooperative mating behavior in this species.

  • Males use a push-up display to defend their territory.

  • This lizard is short-lived, living only about one year.



Appearance :


The side-blotched lizard is a small brownish gray lizard ranges from 1.5 - 2.5 inches long from snout to vent. It has small smooth granular scales on the back, larger scales on the head and limbs, a gular fold, a long thin tail and a dark blue-black mark on the sides of the chest behind the front limbs, which gives this lizard its name. This mark is sometimes faint or absent. The lizards overall color is brown, gray, yellowish, or black, with dark blotches, spots, and sometimes stripes. Often there is a double row of dark spots or wedges on the back, edged with white on the rear. The underside is whitish to gray and mostly unmarked. The throat is mottled with dark and light. Males are more colorful than females, having blue speckles on the upper surfaces, which are most visible during the light phase. Males also have a swollen tail base and enlarged postanals, but no distinct blue coloring on the belly (which can be found on male lizards of many other species.) The throat is marked with blue, orange, or yellow. Males often have many blue speckles on the tail and the posterior of the body.


Range :


The side-blotched lizard is found throughout most of western North America. It is common to abundant throughoutarid and semi-arid regions of the state, excluding most of northern California, the Sacramento Valley, the Sierra-Cascade ranges, and several of the Channel Islands. Its elevation range extends from below sea level to over 8000 ft. Prefers open habitats including desert, coastal scrub, chaparral, grass, juniper, pine-juniper, Joshua tree and valley-foothill.


Habitat :


Side-blotched lizards are found in habitats comprising a wide variety of arid and semi-arid situations with scattered bushes and/or scrubby trees; soil may be sandy, gravelly, or rocky. The species is often found in sandy washes with scattered rocks and bushes. As a diurnal reptile, it is usually the first lizard species out in the morning due to its small size which allows it to warm up quickly. It is active mostly on the ground, but it is also a good climber. The side-blotched lizard is often seen basking on rocks, hopping from boulder to boulder, or running quickly along the ground.


Feeding :


Side-blotched lizards eat a wide variety of insects and other arthropods. Little time is spent foraging. Lizards feed opportunistically on any moving insect of suitable size that passes nearby as they bask or move about their home range. Food also includes scorpions, spiders, mites, ticks and sow bugs. Some vegetable material is eaten either accidentally or possibly for water.


Reproduction :


Biologist Barry Sinervo from the University of California, Santa Cruz has discovered a rock-paper-scissors strategy in the mating behaviour of the side-blotched lizard species Uta stansburiana. Males have either orange, blue, or yellow throats and each type follows a fixed, heritable mating strategy. Orange-throated males are strongest and do not form strong pair bonds; instead, they fight blue-throated males for their females. Yellow-throated males, however, manage to snatch females away from them for mating. The large size and aggression is caused by high testosterone production. Blue-throated males are middle-sized and form strong pair bonds. While they are outcompeted by orange-throated males, they can defend against yellow-throated ones. Because blue-throated males produce less testosterone they are not as large as the orange-throated males, but it gives them the advantage of being less aggressive and able to form strong pair bonds. Yellow-throated males are smallest, and their coloration mimics females. This lets them approach females near orange-throated males and mate when the males are distracted. This is less likely to work with a female that has bonded with a blue-throated male.This can be summarized as "orange beats blue, blue beats yellow, and yellow beats orange", which is similar to the rules of rock-paper-scissors.


The breeding season lasts from March to August. Mating occurs from April to May; egg deposition occurs from late April to August. Females store sperm for delayed fertilization. Side-blotched lizards are monogamous. Clutch size is positively related to size of female, winter rainfall and spring annual production, and inversely related to season and density. Clutch size varies from 1 to 8 eggs (average = 4). Hatchlings appear from June to late September. Development time also decreases with season and is 61 to 77 days. Males and females reproduce the first spring following hatching at approximately (1.72 in) snout-vent length.


Conservation Status :


According to the International Union for Conservation of Nature and Natural Resources, the species Uta Stansburinia is of Least Concern owing to this lizards very large number of occurrences or subpopulations. The total adult population size is unknown but surely exceeds 1,000,000. The extent of occurrence, area of occupancy, number of subpopulations, and population size are large and relatively stable. Additionally, the species occurs in many protected areas, such as national parks, monuments, and wilderness areas. No direct conservation measures are currently needed for this species as a whole.


Side-blotched lizards are monitored annually on Anacapa Island in the park, as part of the park's long-term ecological monitoring program. Transects of coverbaords have been placed in several habitat types, and the number and size of lizards found under the coverboards is recorded several times per year.

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