Tarantulas(Aviculariasp.)

Known to naturalists as bird spiders, the large hairy members of the generaAvicularia,Dugesiella, andAphonopelmaof the arid Southwest are commonly called tarantulas.

Tarantula(Photo by Marvin H. Frost Sr.)

This name originated in southern Italy where, centuries ago, according to a story, in the little town of Tarantum (now Taranto) there developed an epidemic of “tarentism” supposedly resulting from the bite of a large wolf spider (Lycosa tarantula). Victims were affected with melancholy, stupor, and an irresistible desire to dance. Presumably, the Neapolitan folk dance, Tarentella, came about as a result of an effort to develop a cure for tarentism.

Early day immigrants brought to the western hemisphere both the unreasoning fear of spider bites and the name “tarantula,” which they applied to the large and fearsome-looking bird spider of the Southwest. Since that time this superstitious fear has become established among the uneducated and uninformed people of the southwestern United States, where the bird spiders are numerous.

It has been spread and aggravated by prolific writers of western thrillers, published in the pulp-paper magazines. Fantastic tales in which the big spiders followed their victims, sprang upon them from distances of from 6 to 10 feet, and inflicted painful bites resulting inlingering, agonizing death have had wide circulation and have found a credulous audience.

Tarantulas are nearsighted, and their habit of pouncing upon grasshoppers and other large insects on which they prey is probably the basis for exaggerated stories of their jumping abilities. Their strong, sharp fangs can inflict a painful bite, but they use them only rarely in defense against human molestation. Stahnke states that any effects produced appear to be the result of bacterial infection rather than that of poison, although a mild poison is present. Treatment of tarantula bite with iodine or similar antiseptic is recommended.

One species ofAviculariaand several ofAphonopelmarange throughout the Southwest where they are active during spring, summer, and autumn months. They live in web-lined holes in the ground, usually located on south-facing slopes. The males are commonly encountered traveling across country, and are particularly noticeable as they cross a highway.

Preying upon insects, these large and interesting desert dwellers are beneficial rather than harmful to mankind, and deserve protection.

Unfortunately, many become the innocent victims of the wholly unwarranted fear in which they are held because of the fantastic stories regarding their purported poisonous characteristics.

Although not limited to the deserts of the Southwest, conenose bugs, of which there are several species, are commonly associated with subtropical climates.

Certain South American species of the familyReduviidaeare disease carrying and there is evidence the conenoses in San Diego County, California, are infected with a disease-producing flagellate. Lack of large bug populations in close contact with man and ineffective transmission habits protect man in the Southwest from disease contacts. However, the site of the bug’s bite becomes inflamed, and swelling may spread over an area up to a foot in diameter.

In general appearance, conenose bugs resemble assassin and squash bugs, with protruding eyes at the base of a cone-shaped snout and are about the same size. Some species are considerably smaller, while others attain a length of an inch or more.

Since conenose bugs subsist upon animal blood which they suck from the capillaries by inserting the stylets of the proboscis, they seek locations where there is a source of blood. These include livestock barns, poultry houses, and human habitations.

Conenose bugs—Triatoma protractaAdult male (rounded abdomen); Adult female (pointed abdomen)(Photo courtesy of Dr. Sherwin F. Wood)

Studies conducted by Wehrle[5]show that conenoses are parasitic on woodrats and breed in the dens of these rodents. They are also found in meadow vole (mouse) nests. Early in May the winged conenose adults begin dispersal flights, invading human habitations in the vicinity of woodrat dens. Although reported as most active in May and June, they may be expected throughout the summer until October, and are much more numerous in the country than in cities.

During the daytime, the insects remain hidden under rugs, between quilts, or even in bedding or behind drapes. They may be seen during the evening on ceiling beams, walls, curtains, and around windows. They are alert and difficult to catch.

Conenose bugs do not attack people until the victim is quiet or asleep, and may take blood without awakening the host. Immediately after being bitten, however, the victim is awakened by severe itching. The area about the puncture swells and becomes red and feverish. Welts at the point of puncture are hard, and may be 1 to 3 inches in diameter.

About 5% of the people repeatedly bitten develop severe allergic reactions with burning pain and itching at the site of the bite, itching on the palms of the hands, soles of the feet, neck, and groin; general body swelling, and a nettle-like rash over the body. Some persons feel ill, with light depression followed by quickening of the pulse. Othersare faint, weak, and nauseated. In very severe allergy these symptoms may lead to anaphylactic shock and unconsciousness.

Although a specific treatment for conenose bites has not been developed, some physicians use epinephrine. More promising results appear possible with antihistamine preparations (under doctor’s prescription) such as benadryl and pyribenzamine, which have been effective by mouth, and in severe reactions, by intravenous injections.

Matheson[6]writes: “When a blood-sucking insect bites, it is always possible that the proboscis may be contaminated with pathogenic organisms. If such organisms become localized near the point of puncture or gain access to the blood stream, results may be serious. It is always wise to use some disinfectant such as alcohol, tincture of iodine, etc., and to press out the blood, if possible, from bites made by insects.” Antibiotics are frequently necessary to control the extremely high percentage of secondary infections.

Physicians recommend the application of a hot Epsom salt pack over the point of puncture as soon as possible after the bite has been received. Application of antiphlogistine alleviates the severe itching. ACTH is recommended by some physicians. Hydrocortizone ointments reduce the skin eruptions and local pain.

Prevention is more satisfactory than treatment, and since conenoses live in woodrat dens, these rodents should be eliminated from the vicinity. Weatherstripping around all permanent doors and screen doors, tight-fitting, holeless screens in all windows, and fine screens in fireplace chimneys will help to keep the bugs out of houses. Occasionally they may be seen on walls and ceilings in the evening, and may be killed with a flyswatter.

If impossible to keep the insects out of the house, sleeping persons may be protected by the use of mosquito netting. It is especially important that the beds of babies and young children should be safe-guarded because of the danger from scorpions.

Common ant

Bedding should be shaken thoroughly just before children retire, because both scorpions and conenose bugs have a habit of concealing themselves in bedding during the daytime.

Stinging insects all belong to the groupHymenopteraand consist of the familiesApidae(honeybee, etc.),Bombidae(bumblebee),Vespidae(wasps and hornets),Sphecidae(thread-waisted wasps),Mutillidae(velvet ants), andFormicidae(the ants).

Wasp

In general, the only treatment recommended for insect stings is to bathe the parts with ordinary liquid household bluing just as soon as possible after the sting has been received, and apply hot compresses. However, certain specific treatments are advised, depending upon the particular species or condition.

Some persons are extremely susceptible to insect bites and stings, and preliminary work has been done in trying to immunize those sensitive individuals, but, in general, with very little success. The problem of immunizing or desensitizing persons who are allergic to insect bites and stings is one of considerable importance, as such unfortunate persons will testify.

Because of the fact that honeybees are of such great economic importance, not only as producers of an important food but also as pollenizers of fruit, vegetable, seed, and other crops, they will be discussed separately from the other stinging insects.

Everyone is familiar with ants, wasps, hornets, and bumblebees, and there are very few persons who have not had unpleasant experiences with one or more of these groups of insects.

Velvet ants, which are in reality wingless wasps and not true ants, are not as well known as the others, although the little creatures that scurry about like brightly dyed bits of cotton are quite numerous in the desert.

The primary purpose of the sting is to paralyze or kill their prey, although it becomes more important as a weapon of defense with insects which do not prey upon or parasitize other creatures. Although the solitary insects use their poison as a means of personal defense if attacked or imposed upon, the social insects such as ants, social wasps and hornets, honeybees, and others, rally to the defense of their nests and in mass attacks against an intruder may cause painful and sometimes serious injury.

Although the small amount of poison introduced beneath the skin by the sting of one of these creatures usually causes only temporary discomfort, there are sometimes after effects which may be more intense and of longer duration with some persons than with others. In general, stinging insects may be considered more as a nuisance than a menace, although a person attacked by a large number, or subjected to their stings for some length of time, might receive serious and perhaps fatal injuries. Known deaths have been caused by the sting of imported fire ants in southeastern States. The species is believed to be spreading. Treatment by a physician may include the use of ACTH and calmitol.

Although ants and velvet ants are commonly considered as wingless, they are, actually, winged. Male velvet ants have wings whereas the females are normally without wings. The females have a very effective sting, and if picked up or pinched they make every effort to use it, at the same time emitting a peculiar faint squeaking sound.

True ants, of which there are hundreds of species, are social insects living in colonies containing the mother, or queen, which becomes wingless after fertilization; numerous workers, or non-fertile females; and young winged males and females.

Velvet ant

Ants of various species are numerous on the desert, some of them becoming serious household pests, difficult to control.

There are effective ant poisons on the market, but the surest method of control is to find the nest and destroy it. Ants that are household pests usually are either grease eaters or sweet eaters, and the proper poison for the specific type should be obtained in attempting to rid the house of these insects.

Wasps, hornets, yellowjackets, and bees of many species are common in the desert, some species being solitary in habit while others live in colonies or nests which they defend with great pugnacity.

Bumblebee

Although humans have little to fear from these insects if they leave them strictly alone, some species select nest sites beneath overhanging eaves or in attics or lofts, thus becoming persistent pests. They are usually tolerated until one or more members of the family are stung.

Other species are attracted to human habitations by the presence of sweets or other edibles, and make persistent nuisances of themselves. They are capable of inflicting painful injuries, and are greatly feared by many persons.

Not usually serious, these injuries do not respond to any treatment that has yet been developed. Immediate application of strong ammonium hydroxide (household ammonia) is a home treatment which hasbeen found helpful for ant stings, and, in most cases, for the stings of other insects.

A piece of ice held at the point of puncture will relieve the pain and burning sensation in the majority of cases of insect sting.

In serious cases, of course, the services of a physician should be obtained immediately.

At first thought it may seem unjustified to include the common honeybee in a discussion of poisonous creatures of the desert. Although the honeybee is not a desert native, having been imported from Europe, it has established itself in the wild state throughout the Southwest in locations providing adequate moisture and sufficient nectar-producing flowers.

Honeybees on the honeycomb

Throughout much of the United States honeybees are encountered in numbers only in apiaries operated by beekeepers, or in bee trees where the insects have established themselves. In the desert climatic conditions are ideal for honeybees, and they have become widespread and well established.

They obtain water at springs, seeps, waterholes, cattle tanks, dripping faucets, and leaking water containers, often congregating in such numbers around sources of water that they become a distinct nuisance to men and to animals. Individual honeybees are frequently found in flowers, or may fly in through an open automobile window, and sting one of the car’s occupants. Small children sometimes receive stings while playing on white clover lawns or going barefoot. Farm boys maybe severely stung as a result of molesting beehives or throwing stones at bees’ nests in trees or caves.

Normally, poison introduced by the sting of a honeybee is local in effect and little more than a painful inconvenience to the person stung. There are many cases on record, however, of persons and domestic animals receiving stings from so many of the enraged insects that serious and even fatal results have followed.

During the past half century, medical records show a number of deaths each resulting from a single sting. Jones[7]made an intensive study of this problem and was able to show conclusively that occasional individuals become supersensitive to honeybee venom. If persons in such condition receive even the small amount of poison injected by a single sting, the resulting excessive susceptibility may be fatal unless proper treatment is administered immediately. To such persons the honeybee is definitely a poisonous and dangerous creature.

Poison mechanism of worker bee, greatly enlarged.

The poison-injecting mechanism of the worker bee is located within the extremity of the abdomen and consists of a barbed sting at the base of which is attached a sack, or reservoir, containing the poison. Male bees (drones) have no sting, and the queen reserves hers for possible use in battle with a rival queen.

In the act of stinging, the bee forces the tip of the sting through the skin of the victim, where it becomes imbedded, being held by the barbs. In escaping the bee tears away, leaving the sting, poison sack, and attached muscles and viscera. Incidentally, this rupture results in the death of the bee.

Capillarity and the spasmodic movement of the attached muscles force the poison from the sack through the hollow shaft of the sting into the wound.

To counteract this, the first thing that anyone should do when stung by a honeybee is to SCRAPE out the sting. This may be done with a knife blade or even with the fingernail, although the latter is far from sanitary. NEVER PULL OUT THE STING, because in grasping the protruding poison sack between the thumb and forefinger, the sack is certain to be pinched and the poison squeezed into the wound.

Since, under normal conditions, it takes several seconds for the contents of the sack to work into the puncture, prompt removal of the sting with the attached sack prevents much of the poison from being injected.

Application of strong household ammonia just as soon as the sting is scraped out is helpful in allaying the pain.

If a person receives a great number of stings, a physician should be summoned at once. The victim should be undressed, put in bed, and all of the sting scraped out. All parts of the body that have received stings should be covered with cloths soaked in hot water and wrung out. These applications should be as hot as the victim can endure.

Persons who are supersensitive to bee-sting venom show the following symptoms when stung: the skin over the entire body breaks out in lumpy welts, palms of the hands and soles of the feet itch. This is followed by headache, nausea, and vomiting. Breathing becomes labored and heart action is rapid and weak.

As soon as such symptoms are noted, a physician should be summoned or the victim taken to a hospital. Treatment consists of frequent, small, hypodermic injections of epinephrine in the ratio of one part of epinephrine to 1,000 parts of water. Dr. W. Ray Jones[7], who developed and perfected this treatment, reports that it is immediately effective and recommends that all commercial beekeepers provide themselves with hypodermic kits and a small supply of epinephrine.

Even persons who are apparently immune to bee-sting venom through having received bee stings during the course of many years of work in the apiary, may suddenly develop supersensitivity. The treatment is relatively simple, may be self-administered, and has already proved effective in treating serious cases of excessive susceptibility resulting from supersensitive persons receiving bee stings.

Experimental use of calcium lactate to counteract “sting shock” indicates a high degree of success. Physicians should investigate “Death by Sting Shock,” p 234,Science News Letter, April 9, 1955. Use of antihistamines or a hormone of the cortizone family has had some success.

Superficially resembling a tiny, light, golden-yellow kitten, the puss caterpillar is a short, bushy larva of a small gray-brown moth with whitish underwings. When disturbed, the caterpillar rears back on its hind legs and “makes a face.” The species has long been widespread throughout the southern states feeding on the foliage of oak, elm, plum, and sycamore trees. They have been found also in truck gardens and orchards. Recently they have invaded the desert mountains of the Southwest, having been reported by Stahnke as especially numerous in the Globe-Miami area of Arizona, feeding on the foliage of oaks.

Puss caterpillar(Courtesy Dr. Herbert L. Stahnke)

Because of their long, silky hairs, children are tempted to touch them. Under the hairs are small protrusions, each bearing a circlet of very small spines resembling tiny porcupine quills. The venom is injected when these spines pierce the child’s skin and the tips break off, producing a burning, itching, irritated, inflamed area. The welts, ranging in size from a dime to a dollar, are sometimes followed by severe muscle cramps and headache. Not lethal, the toxin may cause enough sleeplessness in a child to reduce his resistance to other infections.

Treatment suggested by Dr. Bernard J. Collopy, Assistant Medical Director of the Miami-Inspiration Hospital of Miami, Arizona, consists of immersing the inflamed area in iced water for thirty minutes. Remove for one minute at ten minute intervals for relief from the cold. The skin may blister and peel at the site much as in the case of a first degree burn, but should heal completely in ten days. Some physicians suggest an opiate for relief of pain in severe cases. Cooling lotions may be applied to relieve the itching.

The coral snake, of which there are two species in the United States, belongs to theElapinegroup, which is represented in the Old World by the cobras and other poisonous snakes. These two species, the coral snake of the Gulf States, and the smaller Arizona coral snake whose range extends into the desert lands of southern New Mexico and Arizona, are the only representatives of theElapinegroup found in this country.

Arizona coral snake(Photo by Marvin H. Frost, Sr.)

The Arizona coral is shy and secretive in its habits, timid rather than pugnacious, and it is so rarely seen that little is known of its habits.

The poison mechanism of the coral snake is somewhat different from that of the pit viper group, to which the copperheads, cottonmouths, and rattlesnakes belong. The teeth of the coral are short, and to be effective the coral snake must chew rather than strike its victim.

The Arizona coral snake is so small—rarely reaching 2 feet in length—and its mouth is so tiny, that it would be very difficult for it to bite an adult human. It is conceivable that a small child playing with one might be bitten.

Because of its close resemblance to several ringed or banded snakes of the desert and also to the Arizona mountain kingsnake, or “coral”kingsnake, of the ponderosa pine highlands of the Southwest, a brief description of the Arizona coral snake is indicated. One of the beautifully spectacular snakes of the desert, it is marked by bands of dark red, cream, and black, which encircle the body. Superficially the markings of the Arizona mountain kingsnake and other tricolored ringed snakes appear similar. However, the red of the kingsnake and of others is usually brighter, and the black bands narrower than those of the coral.

Definite identification is provided by the relationship of the colors to each other, the arrangement on the Arizona coral snake being red, cream, black, cream, red, cream, black, cream. The bands of the Arizona coral snake entirely circle the body and its snout is black.

Thirty species and subspecies of rattlesnakes occur in the United States, more than half of this number being found in the Southwest. Because they have been killed on sight for years, their numbers have been considerably reduced in densely populated areas. For this reason, together with emphasis placed upon their poisonous characteristics by some writers of western thriller fiction, rattlesnakes are considered by many people to be a serious menace in the thinly populated portions of the arid West[8].

Western diamondback rattlesnake(Crotalus atrox.)(Photo by Earl Jackson)

In the hot desert regions of the Southwest rattlesnakes are usually abroad at night during the summer months, as they have no controllingsystem for body temperature and cannot endure the heat at ground surface during the hours of sunlight. In spring and autumn they may be encountered in the daytime but during December, January, and February they are in hibernation and are rarely or never seen.

Their food consists principally of lizards and small rodents such as ground squirrels, rats, mice, pocket gophers and young rabbits. They are sometimes found along irrigation canal banks where they go for water, and because they find rodents congregating there for the same reason. Unless surprised, cornered, teased, handled, or injured, a rattlesnake usually will try to remain hidden or will endeavor to crawl away rather than strike. Because they are attracted to places where small rodents abound, they are sometimes encountered around barns and outbuildings. They occasionally enter abandoned structures in search of food or to escape from the heat of the sun.

Because a rattlesnake may be met at almost any time, except during the winter months, by a person who lives, works, or visits in the desert, he should be ever alert. If hiking or climbing through country where rattlesnakes are known to be abundant, he should wear clothing that will protect him from a possible bite.

Pope[9]states that records kept during 1928 and 1929 show that 98 per cent of snake bites occurred below the knee or on the hand or forearm. When in snake country, the hiker should wear knee-high boots or leggings, and should never place his hand on a rock or ledge above the level of his eyes. In other words, watch your step, and look before you reach! Apparently rattlesnakes may strike at a quick movement and are very sensitive to the body warmth of a nearby warm-blooded creature.

Rattlesnakes belong to the group known as the pit vipers, which includes the cottonmouths and the copperheads. The latter do not occur in the desert, so they do not come within the province of this publication. Snakes of the pit viper group are characterized by a noticeable depression, or pit, found almost halfway between the eye and the nostril, but slightly lower, on each side of the head.

Of the several species found in the desert, some, such as the western diamondback rattlesnake have a wide range, while others are restricted to limited areas. Some species attain large size, while others are quite small; some are inclined to be pugnacious, while others are more or less docile. All are dangerous!

It is not within the scope of this publication to enter into a discussion of the many species, so the reader who wishes to pursue that subject further is referred to Klauber’s publication on the rattlesnakes[10].

There is one rattlesnake of the desert that should be especially mentioned: the sidewinder, or the little horned rattlesnake. It is called sidewinderbecause of the peculiar method of locomotion that enables it to progress in the sandy habitat which it frequents. Unable to get sufficient traction in loose sand by moving as other snakes do, it throws a portion of its body ahead as a loop, thus serving to anchor or pull the rest of the body ahead. Thus it progresses sideways in a looping, or winding, motion most interesting to observe.

Sidewinder or “horned” rattlesnake

Although the term sidewinder is often used loosely in referring to other species of rattlesnakes, it actually applies only to this particular species—Crotalus cerastes.

In snake country, it is important to take a flashlight along whenever there is occasion to go outside at night in summer to be sure that there are no rattlesnakes lying across your path. If you sleep out of doors. keep your bed off the ground if possible. The widely believed statement that, “a rattlesnake will not crawl across a hair rope” is not true, although such a statement will often precipitate an argument.

Persons much in the field should provide themselves with a suction-type snakebite kit, and should know how to use it. Although you stand 200 chances of being killed by an automobile to one of dying from snakebite, the price of a suction-type kit is cheap insurance against that possibility.

If, in spite of all precautions, you or some companion should be bitten by a rattlesnake, first-aid should be rendered at once. This is notdifficult if you have a snakebite kit, and it is possible even if you do not.

The following steps are quite universally accepted:

1. Apply a tourniquet a short distance above the bite (that is between it and the heart) but do not make it too tight. This prevents the blood and lymph carrying the poison from being spread rapidly through the body. The tourniquet should be loosened for a few seconds every 20 minutes.

2. Make a short cut about one-fourth inch deep and one-fourth inch long near each fang puncture with a sharp, sterile instrument. A knife or razor blade sterilized in the flame of a match will do.

3. Apply suction to the cuts. If no suction cup is available, the mouth will do if it contains no open sores.

4. If antivenin is available, administer it according to instructions, but, if possible, this should be left to a physician. (Recent experiments with antivenin indicate that, in some cases, its reaction may be harmful and that it should be administered only under the care of a physician.)

5. Get the patient to medical help as soon as possible, continuing the first-aid treatment enroute. Keep the patient quiet and do not let him get frightened or excited. Rather than require the patient to walk or otherwise exercise, medical aid should be brought to him.

6. If medical help is not available, and if Epsom salts can be obtained, apply cloths soaked in a strong, hot solution of Epsom salts over the cuts. The sucking, however, should be continued for at least half an hour, preferably for an hour or more. Never give alcoholic stimulants or use permanganate of potash. Snakebite kits give complete instructions; follow them carefully.

Poison mechanism of the rattlesnakeRedrawn from Dr. Fox

Rattlesnake venom contains digestive enzymes which attack and destroy tissue, and because of this and the possibility of bacterial infection introduced by cutting the skin, another method of treatment—cryotherapy (treatment with cold)—advocated by Dr. Herbert L. Stahnke, Poisonous Animals Laboratory, Arizona State University, seems to be gaining more and more support. This technique is designed to prevent and control the chemical action of the venom and of bacteria, as well as minimizing stress. This latter action is extremely important, since recent research work has indicated that the physiological products produced by the body under stress may more than double the toxic effects of the venom. Cut-and-suction, or any similar treatment, tends to greatly increase stress.

The following description of treatment is excerpted from “American Journal of Tropical Medicine and Hygiene,” Volume 6, Number 2, March, 1957,The Treatment of Snake Bite, by Herbert L. Stahnke, Fredrick M. Allen, Robert V. Horan, and John H. Tenery:

1. Place a ligature (tight tourniquet) at once between the site of the bite and the body, but as near the point of entrance of the venom as possible.

2. Place a piece of ice on the site while preparing a suitable vessel of crushed ice and water.

3. Place the bitten hand or other member in the iced water well above the point of ligation.

4. After the envenomed member has been in the iced water for not less than 5 minutes (N.B. research has shown that the danger generally attributed to a ligature is not present when the member is refrigerated), remove the ligature, but keep the member in the iced water for at least 2 hours.

5. Pack the envenomed member in finely crushed ice. This hypothermia must continue for approximately 24 hours, and the patient must not be permitted to chill, since this increases body stress.

6. Change from hypothermia to cryotherapy. This is accomplished as follows: after the first 24 hours following the bite, the patient should be kept somewhat uncomfortably warm—that is, to the point of perspiration—and encouraged to drink much water. This step is exceedingly important. Unless the patient is kept uncomfortably warm the proteolytic portion of the venom will not leave the site of the bite. Consequently, when hypothermia is stopped, the concentration of this part of the venom is greater and the tissue destruction will be proportionately increased. Hypothermia should be avoided entirely if this step is not meticulously observed.

Western black-headed snake(Tantilla eiseni).(Courtesy San Diego Natural History Museum)

Sonora lyre snake(Trimorphodon lambda).(Photo by Marvin H. Frost, Sr.)

7. The warm-up period after Cryotherapy is important. This must be done gradually. Remove the member from the crushed ice and place it in ice water (without ice). Allow the water to warm to room temperature.

Dr. Walter C. Alvarez in theSanta Fe New Mexican, 8-18-57: “Recently, Dr. Wm. Deichmann, John E. Dees, M. L. Keplinger, John J. Farrell, and W. E. MacDonald Jr. reported that hydrocortizone is a life-saving drug when given to animals that have suffered poisoning from rattlesnake venom. Instead of only the 17% of the untreated animals that survived, 75% of treated animals were saved.”

The southwestern desert regions are credited with harboring several genera of snakes whose grooved back teeth indicate that they may have poisonous properties. Of these, the Sonora lyre snake[11](Trimorphodon lambda) and the Mexican vine snake (Oxybelis aeneus auratus) are the only species of sufficient size to be considered as even remotely dangerous to mankind. Species of the generaTantilla(black-headed snake),Hypsiglena, andSonoraare too small and too difficult for the amateur to identify to be considered in this publication.

More conflicting statements are made about the Gila (HEE-lah) monster than about any other desert reptile. Some persons insist that it is not poisonous, others are sure that even its breath is poisonous: that it spits or blows its poison: that the animal has no anal opening, hence undigested fecal matter remains in the body, decays, and is the basis of its poison; and so on.

Gila monster(Heloderma suspectum).

Here are the facts. The lizard is poisonous and its bite may be serious, possibly fatal[13]. Its breath is not poisonous, and although the animal seems to have a chronic case of halitosis, this has nothing to do with its dangerous properties. It does not spit poison, but when angered it frequently hisses, the outcoming blast of air sometimes carrying droplets of saliva. It has a normal anal opening and voids fecal matter in a perfectly normal manner. It is not a walking septic tank as many persons believe.

Largest of the lizards native to the United States, and the only species found in this country which is poisonous, the Gila monster rarely attains a length of 2 feet. Average specimens are smaller. Its beady skin, heavy body, short legs, and waddling gait set it apart from all other lizards except its close relative, the also poisonousHeloderma horridumof Mexico. The Gila Monster is a spectacular black and corral color, while the other is black and yellow.

Gila monsters are found in southern Arizona, their range extending northwestward into the southern tip of Nevada and southwestern Utah.

Underside of Gila monster showing anal opening. This photograph is advanced as proof that the Gila monster is a perfectly normal creature in this respect.(Photo courtesy of Poisonous Animals Research Laboratory, Tempe, Arizona)

Food consists chiefly of bird and reptile eggs, young rodents, and such small or juvenile creatures as it is able to capture. It is especially fond of hen eggs and may be kept in captivity for a long time without other food. It is also fond of clear water, which seems strange because of the scarcity of this liquid in the natural habitat of the lizard. If provided with a basin of water it may lie partly submerged for hours.

Occasionally encountered ambling across stretches of open desert, especially in the spring, the Gila monster is normally docile and bends every effort toward escape among the stiff stems of some bush or beneath the protecting spine-clad stems of a cactus plant. Sometimes an individual with a “chip on its shoulder” may be met, or one in a normal state of mind may be teased or prodded into anger, when it advances with open mouth, sputtering and hissing.

When aroused, the Gila monster is remarkably agile, making quick turns of its head to snap at nearby objects. If it secures a grip, it hangs on with bulldog-like tenacity, grinding the object between its teeth.

Gila monsters reproduce by means of eggs which are about 2½ inches long with a tough, parchment-like skin. From 5 to 13 eggs are deposited by the female in a hole which she scoops in moist sand in asunny location. After laying the eggs, she covers them with sand, and leaves them for the heat of the sun to hatch.

Poison mechanism of the Gila monsterRedrawn from Dr. Fox

The Gila monster’s tail serves as a storehouse of nourishment, being thick and heavy in times of plenty, and thin and rope-like in the early spring when the reptile first appears after months of hibernation, during which time it has lived on the reservoir of fat stored in its tail.

The poison of the Gila monster is produced by glands in the lower jaw. To be most effective, the poison must be ground into the wound through action of the grooved teeth, the process taking a little time. Bitten persons who immediately have broken away sometimes show no effects of the venom, therein lying the basis for the widespread statement that Gila monsters are not poisonous.

Bitten persons who have been unable to release themselves show symptoms of poisoning similar to persons suffering from rattlesnake bite, although the poison is more neurotoxic in action. Breathing and heart action are speeded up, followed by a gradual paralysis of the heart and breathing muscles.

Treatment is essentially the same as that for rattlesnake bite, which is described earlier in this booklet. A physician should be summoned at once. Stimulants are dangerous, and no one should be permitted to give the patient any alcohol whatever.

Prevention is much simpler than cure, so Gila monsters should be allowed to mind their own affairs unmolested. Normally they are not pugnacious, and it would be very difficult for one to bite a human unless it were being teased or handled or were stepped upon by a bare-footed child. Please do not kill or capture Gila monsters. These interesting lizards are a unique feature of native desert wildlife threatened with extinction. Please leave them for other people to see and enjoy. Furthermore, the Gila monster is protected by State law.

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