SPECTRUM ON WINGS

There is a flash of blue-green color before your eyes, just for a split second. You do not realize what has flown practically into your face until your eyes focus a few feet ahead, and you see a gorgeous creature gracefully flying in a half-circle. Now it is going to settle down on a damp place, in the path just a few feet behind you, where it had been peacefully drinking water until you came along and almost stepped on it.

It is the Pipe-Vine Swallowtail butterfly, which you have seen before, but never at such close range. With wings folded up over its back, the tongue uncoils from beneath its head and begins to pierce the damp sand to secure the much-needed water. The colors on the underside of the wings, glistening in the bright sunlight, are a mixture of blue-green with bright red spots, a combination which only nature can produce.

Little do most people realize that there are between four and five hundred different kinds of butterflies and close to three thousand different moths found within the state of Arizona. Some are found only in certain mountain ranges and no other place in the whole world. For example, the Pallid Hackberry butterfly is found only in the canyons of the Baboquivari Mountains, in Pima County; the Ursus Skip-per has been found only in a few places in the mountain ranges in the southern part of the state, and no other place.

The question “What is the difference between butterflies and moths?” is frequently asked by people who are not familiar with these insects. The answer is that as a rule butterflies are diurnal in their habits, usually flying between sunrise and dusk, and very rarely flying at night. However, it is true that several species of moths also fly during the daytime; but the great majority of them are nocturnal, flying in the evening and during the night. A more definite distinction is based upon the anatomy of the insect, chiefly upon the structure of the antennae or feeler. As a rule, butterfly antennae are club-shaped, whereas in the moths the antennae are not club-shaped but are of various other forms. For instance, some moths have very thin, thread-like antennae, tapering to a fine point; others have feather-shaped antennae; and some have heavy antennae, with one side smooth, the other side covered with short bristles. There are many variations and modifications of these forms.

This brings up the interesting question: Why are so many butterflies and moths found in Arizona? The reason is that Arizona is located in a unique position, with the Continental Divide on the east and the Sierra Nevada Divide on the west. The interior of the state possesses numerous mountain ranges, plains, deserts, and plateaus, with semi-tropical and tropical influences in the mountain ranges in the southern part of the state. Evidence that might fix the extent of time since the latest tropical climates in this region is meagre, but available data seems to indicate the possibility of 20,000 to 50,000 years ago. What we now call Arizona was quite tropical during this period.

Many species of insects which are now found in small numbers in Arizona are much more common farther south in Mexico and the different Central American countries. As the tropics receded south into Mexico, the deserts, due to the lack of moisture, took over the general flat lands and low ranges of the hills of Arizona. The various species of plants and insects were left in the mountain ranges where more rainfall occurs. Thus the mountain ranges, which often go up as high as 8,000 to 10,000 feet or over, are islands sur-rounded by deserts.

In summer, some storms come from Mexico. However, most of the rains are local in character and are caused by winds blowing from the Gulf of California and the Pacific. They contain a vast amount of moisture, although they are heated above dew-point in crossing the hot, low desert. The winds retain this moisture until they meet the high mountains in Arizona and New Mexico. Rising toward the moun-tain tops, they become sufficiently cooled so that their PIPE-VINE SWALLOWTAIL (Papilio philenor L.) The Pipe-Vine Swal-lowtail is often seen sipping water from a damp spot along a stream. Its gaudy colors are irridescent in the bright sunlight. Photograph by Rudolph Wm. Sabbot.

(The photographs on these pages are of actual specimens and have not been painted nor altered in any way. They have all the natural colors they had when collected. The specimens were mounted to show the beautiful colors, as it is almost impossible to photograph live specimens and show the delicate colorings to best advantage.) GALBINA MOTH (Agapema galbina Clem.) This interesting moth occurs in Texas, Arizona and Mexico. It has no mouth parts with which it can feed while it is a moth; the food on which it lives during the moth stage is stored in the body during the time it is a caterpillar. This is true of most of the large silk spinning moths.

TRI-COLORED LICHEN-MOTH (Cisthene schwarziorum Dyar) Because of its small size, which is only % of an inch in wingspread, this little beauty is not noticed around lights at night. It is quite common. Few people realize that size has nothing to do with the beauty of insects; some of the smallest are the most brilliantly colored.

ROSY IO MOTH (Automeris pamina aurosea Neum.) Can easily be distinguished from other moths by the round eye spots on the lower wings. The top wings are a soft rose color with delicate shading of light brown. It inhabits the canyons in Arizona where oak abounds, but is never common.

TYPHON SPHINX MOTH (Pholus typhon Klug.) Found in southern Arizona and northern Mexico. The caterpillars often do considerable damage to Trumpet-vines by eating off all of the foliage.

TERLOOT SPHINX MOTH (Arctonotus terlootii Hy. Edw.) Rare in the United States, being found in Madera Canyon in the Santa Rita Moun-tains of Arizona. It has been found more commonly in Sinaloa, Mexico, but little is known of its habits. The soft green color will often fade when exposed to sunlight for any length of time, turning to a brownish-gray.

BRILLIANT MIRACAVERA (Miracavera brillians Barnes) It is not often that we find green color among this group of Noctuid moths. Most green moths will fade to a dull white if exposed to bright sunlight or to moisture. This particular species is far from common in the mountain ranges of Arizona.

DELICATE GREEN GEOMETRID (Nemoria delicataria Dyar) This group of moths comes from caterpillars which some people call “measuring worms.” The species is well named for the delicate green wings, fringed with pink.

GOLDIE MOTH (Neumoegenia poetica Grt.) Found quite commonly in the lower part of Madera Canyon in the Santa Rita Mountains during August. The gold luster is due to a refraction of the light by the many tiny scales on the wings.

BUTTERFLY LIFE CYCLE THE MONARCH (Anosia plexippus)

Moisture is precipitated, bringing welcome relief to the land.

In the mountains of Arizona, more rain is recorded dur-ing July, August and September than at any other time of the year. During this time approximately 43 percent of the entire year's rainfall occurs. The second period, December through March, is one of longer duration, but it furnishes less water. Only 35 percent of the year's rainfall occurs dur-ing these four months.

These conditions establish three definite seasons within a year for butterflies and moths to occur in abundance. The rains which occur during December through March will bring out the plants at the lower elevations, on the floor of the desert and the low hills. By March, as the sun warms the soil, the seeds of the annual plants germinate and the perennials will put out new growth. This in turn furnishes food for the young caterpillars. So we have March, April, and the first part of May as the spring season. For example, the little Pima Orange-tip butterfly is quite common on top of “A” or Signal Mountain just to the west of Tucson. If there has been sufficient rain during the winter months to bring up the proper species of wild mustard, the butterfly can lay her eggs for the next year's crop of butterflies. During the summer rains, this species of wild mustard will not germinate and grow, so the Pima Orange-tip is found only in the spring.

As the low hills and the desert become dry in May, June and July, the butterflies at higher elevations begin to appear, such as in the White Mountains in the central-eastern part of the state. By this time, the snow has melted, the sun has warmed the soil, the plants begin to grow, and the butterflies are out in profusion in the meadows. It is here that we find many species closely related to the Colorado forms, because of the close relationship of plants and similar alpine conditions which are found in Colorado. This season is over, to a great extent, by the first of August. A short season prevails at high elevations of 8,000 feet and over.

The third season is from the last half of July to the middle of October at elevations of 2,500 to 7,500 feet, in the lower mountain ranges. This season is by far the most productive in butterflies and moths, for at this time we have 43 percent of the whole year's rainfall. A greater variety of plants grow at this elevation because of the warm climate and the large amount of rain. This in turn produces the semitropical and tropical species which have been isolated in the mountain ranges for thousands of years. The species found in these mountains will not venture out on the desert as their food plants grow only in the mountains and at this time of the year. It is too hot for them on the floor of the desert; the heat would soon dissipate all the moisture from their bodies. Nature has provided them with no adaptation to resist evaporation, so they are confined to the canyons of the mountains where they fly in abundance.

The females of all butterflies and moths lay eggs on the plant which is the chosen food plant of the species. The eggs hatch into caterpillars, and if the egg is not laid on the correct plant, the caterpillar will starve rather than eat just any plant. It is by instinct that the female will lay her eggs only on the right kind of food. Often a female will lay from 250 to 500 tiny eggs, but not all will come through to become the beautiful butterflies and moths that we see, as a large percentage is destroyed sometime during the three stages through which they must pass before becoming adults. If all the eggs from the females were allowed to mature to adulthood, it would be only a very short time until the caterpillars would consume all the vegetation, and we humans would be out of luck for any food. Nature had a wonderful way in which to keep things in perfect balance, at least until man came along. We will all admit that those pesky weeds in our gardens or in our fields of grain could easily be spared to be eaten by caterpillars, and we would be glad to have them do so, but it seems that things just don't work out that way. After the egg has been laid, it takes five days to two weeks for it to hatch as a tiny little caterpillar. As a rule, he will at first eat most of the egg case from which he has hatched; then he will hunt around for a nice tender leaf to eat. He will continue to eat for about four or five days, and by this time he has eaten so much, and his skin is so tight, that he has to shed this skin in order to make more room to grow. The skin loosens and out he crawls, with a new and much larger size skin. Most caterpillars will shed the skin about five times during the caterpillar stage, growing and getting larger each time. Some will shed as many as nine times; it depends on the species. Each kind of butterfly or moth has a different egg, as well as a different-looking caterpillar.

After the caterpillar is full grown, he will go into the third phase of which is the chrysalis or pupa or cocoon. (Most butterflies do not spin cocoons, but change into pupae.) He does this by spinning a small button of silk on a tree trunk, branch, bush, or rock. After the button is spun, the caterpillar will hang upside down by what we might call his hind legs. Then his skin will peel off for the last time, and this time he is no longer a caterpillar, but an odd-looking creature called a pupa. Sometimes the pupae are highly colored, ornamented with gold or silver; some are green; others look like a piece of wood. It depends on the species.

In the moths, it is somewhat different. Some "spin up" like butterflies, others spin cocoons, but the larger number burrow down into the ground or go under a pile of leaves to change into a pupa. In Arizona, where it gets quite warm during the summer days, the pupa could not live if it were exposed to the bright sunlight all day. So nature has provided the caterpillar with the instinct to burrow down into the soil where it is cooler, at the base of a plant or near a rock to change into a pupa. In some species nature has provided the pupa with a heavy coating to keep it from drying out in case of a very hot year with no rain. Some pupae have stayed alive for ten years in the soil, without emerging. However, most of them will stay in the dormant stage as a pupa for only one year; some will hatch within two weeks after changing to a pupa. Again, it all depends upon the species.

When the butterfly or moth first emerges from the pupa, it is not full-grown as we see it flying around. It is a nondescript, longbodied creature, with very short wings. The wings are soft, pliable, and wet. After crawling out of the pupa case, the newly hatched butterfly-or moth-crawls to find a place to hang with its body in a horizontal position so that the wings will be free to expand downward. With a suitable place found, the wings very slowly develop to their natural size; this often takes from one to two hours. As the wings expand, the long body gets shorter, as fluid is pumped from the body into the veins of the wings. After the wings have reached the full size, the insect will not move for several hours. The fluid in the veins of the wings must harden before flight is possible. The first solo flight is often just a few feet, but the insect soon becomes used to its wings and is flying around in your garden, or in the canyons of the mountains.

All moths and butterflies, regardless of size, shape or color, have to pass through these four stages of life.

The rains in Arizona have a great influence on the number of butterflies and moths which are found in the state. This is true of the whole Southwest, but especially so of Arizona. If there is no rain, there is no moisture for plants to grow on; if there are no plants, the caterpillars have no food. So again Mother Nature has provided many species with enough vitality to last several years in the dormant, pupal stage; if necessary, until there is enough moisture to produce plants.

In some canyons of the lower mountains, where the heavy summer rains occur, there are about ten different kinds of moths to every kind of butterfly. Most moths fly at night because they are not equipped by nature to withstand the evaporation which takes place during the daytime. At night, when when it is comparatively cool and the moisture from plants and soil is not evaporating so rapidly, moths are out in large numbers. However, some moths do fly during the day, but such species are few, and as a rule occur only where there is moisture either from the ground or from plants.

Have you ever noticed the swarms of moths around electric lights at night, or around your gasoline lantern when you are camping? Have you ever taken the time to examine these creatures to see what they actually look like? I am sure that if you have you have been amazed at the different sizes, shapes, and combinations of color. The semi-tropical conditions of Arizona produce some especially colorful moths. Have you ever stopped to realize that all these moths which you see have at one time been caterpillars?

The smaller mountain ranges of Arizona could easily be called a biologist's paradise. So little is known about the birds, mammals, land snails, plants, and insects which abound in the canyons of these desert islands. It is true that several books have been published on these subjects, but the actual understanding of the ecology is a task which in time can be worked out only by the specialists in each group. It is the opinion of this writer that Arizona is fabulously rich in life forms. Most biologists do not realize this.

No matter where you look in Arizona's mountains, canyons, desert or rangelands, you'll find a spectrum on wings. The state harbors between 400 and 500 kinds of butterflies, nearly 3,000 different kinds of moths.