Lizards [plus Beetles and Scorpions but only One] Snake of the Desert

CSU Biology 1018? on 25 - 27 May 2007

Mr. William (Bill) Presch, (MA) Instructor

fringe toed.jpg

I.                    Ectothermic, taking energy from the sun

a.      Deserts (under 25 cm of rainfall) are a good place to live

b.      Desert is a growing area

                                                              i.      Due to:

1.      Global warming, whatever the cause (nature or man-made)

2.      Perhaps, the 23.4 degree tilt of earth on a 41K year cycle

a.      “Milankovitch cycles--of precession, obliquity, and eccentricity—repeat approximately every 21, 41, and 100 thousand years, respectively.”

                                                           ii.      LA may become a desert


II.                Justification

a.      Great schedule; 9AM activity begins; afternoon siesta; early evening

b.      Can traps (wait for your species to show up)


III.             Anatomy/Systematics (diversity of life and relationships; see ITIS)/Morphology (shape and form can determine most primitive)

a.      Vocabulary (see

                                                              i.      Diurnal, active in day; rests at night

                                                           ii.      Dorsal/ventral/lateral, back and bottom and side

                                                         iii.      Elongate chin shields

                                                         iv.      Imbricated, overlapping or layered

                                                            v.      Anal plate, “An embryonic plate formed of endoderm and ectoderm through which the anus later ruptures”

                                                         vi.      Hemi-penis (penii, pl.)

                                                       vii.      Preocular scales, in front of the eyes

                                                    viii.      Rostral scales, the median plate on the tip of the snout above mouth

                                                          ix.      Pineal gland, tiny pine cone structure in brain

                                                            x.      Parietal eye (L. “of the wall”), or third eye on dorsal side


IV.             Behavior

a.      Not particularly social

                                                              i.      No alpha lizards

b.      May live within a 40 meter radius of birth

c.       Bipedalism, pros: ability to see better when moving fast;

d.     Bites (UNLV via medevac; otherwise, go to Barstow Hospital or Loma Linda University Hospital; take head of snake)

e.      r/K selection for success in a particular environment

                                                              i.      r-selected, many hatch, but few make it to adulthood

1.      good strategy in unstable or unpredictable environments

                                                           ii.      K-selected, few offspring, but most make it to adulthood

1.      Stable and predictable environments

2.      Large bodies, long life-span


V.                Particular Species of Turtles

a.      Gopherus agassizi (aka desert tortoisie)

                                                              i.       $10M invested and still don’t know anything


VI.             Particular Species of Lizard (Squamates of the East Mojave; * seen)

a.      * Gambelia wislizenii (aka Leopard lizard)       

                                                              i.      Keyed out: 1b, 4a, 5a, 6b (round), 11a (sex), 12a, 13a, 14a, 15a, 16b (not), 20a, and 21b=

                                                           ii.      Carnivorous, other leopard lizards, insects;

                                                         iii.      will bite, not poisonous

                                                         iv.      Good visual acuity

b.      * Uma scoparia (aka fringed-toed lizard)

                                                              i.      Prefers wind-blown sand (gravel is too big)

                                                           ii.      Temperatures around 103 (39C) up to 106, 110

                                                         iii.      Under stress, eats ants

                                                         iv.      Roadrunners like them

                                                            v.      Backward nostrils

                                                         vi.      Face adapted with shovel and nose to get into sand

                                                       vii.      Scales cover eyes

                                                    viii.      Found on the edges of sand dunes, not gravel

                                                          ix.      Runs on sand due to fringes on back of hind feet

                                                            x.      Long 4th finger to flick sand out of eye

c.       * Phrynosoma platyrhinos (aka horn-toad lizard)

                                                              i.      Depressed body shape; 13% of which is stomach

                                                           ii.      80-90% of diet is ants (Horton 1955)

                                                         iii.      Favors Joshua Trees and Kelso dunes

                                                         iv.      Only moves 3-4 feet

                                                            v.      Easy to catch

d.     Coleonyx variegatus (aka banded gecko lizard),

                                                              i.      Night time

                                                           ii.      Found on grid cans

                                                         iii.      makes narking noises

e.      Cnemidophorus tigris (aka western whip tail lizard),

                                                              i.      Extremely smart

                                                           ii.      Hence, neurotic and paranoid

f.        Crotaphytus insularis (aka collared lizard)

                                                              i.      On the side of the road and on rocks when temperature is 94 degrees

                                                           ii.      Changes color due to temperature (lighter at higher temperatures

                                                         iii.      Close relative of the leopard lizard

g.      Dipsosaurus dorsalis (aka desert iguana)

                                                              i.      Prefers 95- 115 degrees

                                                           ii.      Bipedal at 110-115 degrees

                                                         iii.      Sees and hears well; moves fast

h.      Sauromalus obesus (aka chuckwalla)

                                                              i.      Common around DSC

                                                           ii.      Herbavorous

                                                         iii.      Inflates itself inside creavase

                                                         iv.      Indian catch and eat them (using a hook to deflate)

i.        Callisaurus draconodies (aka zebra lizard)

                                                              i.      Speedy, really fast

                                                           ii.      Found in rocky gravel

                                                         iii.      Also bipedal

j.        Urosaurus graciosus (aka long tailed brush)

                                                              i.      Look in creosote brush, live on branches

k.      Uta stansburiana (aka side blotched lizard)

                                                              i.      Common, found everywhere

                                                           ii.      Only have a 3 year life span

l.        Sceloporus magister (aka desert spiny lizard)

                                                              i.      Large scales

                                                           ii.      Pineal gland (3rd eye)

                                                         iii.      Parietal eye

                                                         iv.      Lives on cattle fencing

m.   Xantusia vigilis (aka desert night lizard)

                                                              i.      Can’t distinguish male or female without dissection

                                                           ii.      Living young,

                                                         iii.      Lose tail or drop tail (fat reserve),

1.      Can grow a new one

2.      Used for stability


VII.          Beetles

a.      Tenebrionidae (darkling winged beetle)

b.      Eleodes (species)


VIII.       Snake Species (Squamates of the East Mojave)

a.      Masticophus flagellum (aka red racer, coachwhip)

                                                              i.      Key out as 1b, 4b, 35a, 36b, 37a, 39a, 40b, 46a, 47b, 49a, 50b, 52a, 53a=

                                                           ii.      Fast; bites; shits on you.  

                                                         iii.      Diurnal; will eat side winder; stands up. 

                                                         iv.      Visual—big eyes; intelligent

b.      Western blind snake, primitive; on DSC site

c.       Glossy snake, early AM

d.     Common King snake, less common

e.      Western shovel-nose, attitude

f.        Spotted leaf-nose

g.      Long-nosed snake

h.      Gopher, eats rodents (especially mice around DSC)

i.        Speckled rattlesnake, DSC (will need MedEvac)

j.        Mojave green rattlesnake, venomous—aids digestion, large and slow

k.      Sidewinder rattlesnake, less venomous than Mojave green; only touches sand twice per side, due to heat of sand


IX.              Political Issues

a.      County or state roads inside the federal NPS

                                                              i.      State 199 through Death Valley (charge, even if you are driving thru)

                                                           ii.      County roads to in-holdings

                                                         iii.      19th Century Congress, 2773

                                                         iv.      BLM, Jerry


X.                 Field Work

a.      Motorola Family Radio on Channel 1 (462.5625, the national call channel)

b.      Safety equipment (crowbar)

c.       Drive road at 45mph through several habitats

d.     DSC-KelBaker Road-Kelso Depot-Cima Volcanic Fields (26 May)

                                                              i.      9:05 AM, Marsh hawk

                                                           ii.      9:14 AM, two turkey vultures (black with gray trailing on wings)

                                                         iii.      9:30 AM, red tail/gold eagle nest at 35° 08.28/115° 42.3 (84 in shade; 94 degrees in fine sand)

                                                         iv.      9:37 AM, road runner

                                                            v.      9:40 AM, Kelso Depot: helper engines on one of the steepest grades in the western US (Union Pacific; GE, laboratory engineering, testing new Evolution hybrid drive, 4400 horsepower 207-ton engine)

                                                         vi.      9:48 AM, red hawk

                                                       vii.      10:02 AM, Kelso Sand Dunes at 34° 53.537/115° 41.958 (2600’), from Lake Mohave about 55K years ago; beach sand.  See desert conservation plan.

                                                    viii.      11:18AM, 34° 53.795/115° 42.332 at 2572 feet (110 degrees), fringed lizard

                                                          ix.      11:37 AM, 2 fringed toed at 34° 53.711/115° 42.229 at 2563 feet

                                                            x.      11:40 AM, horned lizards, eats Harvester ants

                                                          xi.      1:30 PM, 35° 10.055/115° 29.824 at 3887 feet (126 degrees)

1.      Joshua Trees

2.      Too dry this year (2nd of drought)

3.      Tigerus (aka western whip tail)

                                                       xii.      1:40 PM, Cima, gravel looking for chuckwalla (94 degrees ambient; 118° on rock face, 134.6° on gravel)

                                                     xiii.      2:20 PM, red tail hawk

                                                     xiv.      2:22 PM, red tail hawk (both near the nest seen earlier)

e.      Trap Can Grid

                                                              i.      Largest in the Southwest

1.      CSUN set out 40-45 cans in 1974

2.      Total 124 on 20 meter transcepts, covering 55K sq meters

3.      Jason’s finding no edge effect, equal chance

4.      Salt flat up the alluevial fan, sand to rocky

5.      Bigger animals out later, in earlier

6.      Disadvantages:

a.      Species learn location after 3 days; one month later, they forget

b.      Potential for local habitat destruction;

c.       Potential to disrupt social behavior and predation

d.     Trap saturation is possible

7.      Collecting via use of a fiberglass noose pole


XI.              Preservation of Collected Species

a.      Glass bottle of 70% ethanol; storage in the dark

b.      Injection of 10% formalin

c.       Histology studies use stain

d.     Ward’s or Carolina Biological for supplies


XII.           Web References

a.      Peter Whitehead, “Causes of Climatic Change” at (accessed 1 June 2007)

b.      Laurie Duncan, “Global Climate” at  (accessed 1 June 2007)

c.       “ITIS—Interagency Taxonomic Information System” at (accessed 29 May 2007)

d.     “Bipedalism”at (accessed 29 May 2007)

e.      “Dust Devils” at (accessed 25 May 2007)

f.         “r/K Selection Theory” at (accessed 28 May 2007

g.      “William Presch” at (accessed 28 May 2007)

h.       “Tenebrionidae website” at (accessed 28 May 2007)

i.        “Uma scoparia” at (accessed 28 May 2007)

j.        “The Effects of Trapping Design on Demographic Estimates...(1980)” at (accessed 29 May 2007)


XIII.        Bibliography

a.      Peterson’s Guide, Reptiles and Amphibians (2003)

b.      UCLA dissertation 1960-1970s on dust devils (whirling dervish)

c.       William F. Presch, “Evolutionary osteology of the Iguanid lizard genus Phrynosoma,” MA Thesis, San Diego State College.

d.     William F. Presch, “Evolutionary Osteology and Relationships of the Horned Lizard Genus...” (1969); see (accessed 29 May 2007)

e.      Jason Wallace, “Population Abundance and Diversity of Reptiles in the East Mojave Desert, Soda Springs Area,” MA Thesis, California State University, Fullerton, 2007.



Compiled: 25 May 2007; revised, 26-29 May 2007 and 1 June 2007