Insects, centipedes, spiders and scorpions are all arthropods or animals that wear their skeletons on the outside of their body. However, they are not all “bugs”. They differ in several ways. Insects have three main body sections – the head, thorax and abdomen, six legs and two antennae.

A most successful species, insects have been around since before the dinosaurs appeared, or about 400 million years. They can be found everywhere – on mountains, near the sea, in the sea and other water, and in the desert. They are the dominant life force on earth, numbering more than all other species combined. Beetles alone may account for over a million species. Without them life as we know it would disappear since they help plants reproduce, clean up dead and decaying animals and plants and provide the main food source for many other animals. As much as we may dislike some species, the majority, or over 97%, are considered “beneficial” to mankind.

Some of the insects, which can be found here in our Southwest desert habitat, include beetles, butterflies and moths, walking sticks, bees, wasps, ants, grasshoppers, crickets, flies, mosquitoes, and cockroaches.

Beetles

Beetles are more numerous than any other kind of creature outside the microscopic in the world. They have two hard front wings and two soft back wings that are usually kept tucked away. There is a hard shield that covers the first section of the thorax and first pair of legs. Beetles clean up dead animals, decaying plant matter, animal dung and also feed on other insect which we consider pests.

The most familiar to us is the little red or orange spotted ladybird beetle, or ladybug, which is a voracious predator. It is found almost everywhere and is used as a pest control agent by gardeners, nurseries and agricultural enterprises. Most are aware that millions of these ladybugs live part or all of the year on Sky-Islands like Mt. Lemon.

Butterflies and Moths

Everyone’s favorite insect would most likely be the butterfly. They provide brilliant spots of color flitting about our gardens in stripes, spots and patterns of every hue. Their complete metamorphosis from caterpillar to adult is one of the most fascinating transformations in nature. Some butterflies, such as the monarch, migrate vast distances. Millions fly a round trip of thousands of miles from North America to Mexico and even South America and back. To attract butterflies to your yard, plant lilacs, snapdragons, cosmos, daisies and “butterfly bush” or buddleia. See our gardening section for more info on other plants.

Moths are the butterflies of the night, usually hiding during the day. Only experts can usually tell the differences between butterfly’s and mouths. They are generally not as colorful although the Luna moth is bright green tipped in purple with long tails and a wingspan of four inches. It is not found in the western states where the smaller, brownish gray armyworm moth is more prevalent as is the “Hawk mouth’ which approaches hummingbirds in size. Moths hold their wings spread out where butterflies hold their wings together. Butterfly antennae are long with knobs at the end. Moth antennae are shorter, without knobs and may be fuzzy. They also go through complete metamorphosis like their close cousins.

Walking Sticks

Stick insects are able to mimic twigs even when they are on the move. Their stride is slow and swaying and resembles the motion of branches blowing in the wind. They are so perfectly camoflauged that they are difficult to spot. They have no wings and are usually brown or green. Often reaching a length of around three inches, they dine on other small insects. They have the ability to grow new legs if one is lost. Nearly all stick insects are female and lay fertile eggs without having to mate.

Bees, Wasps and Ants

Most bees live in colonies with queens, males and female workers. They gather pollen, make honey, raise the young and guard the nest. The queen may live as long as five years. They also have stingers that can cause severe reactions in allergic individuals.

The most well known is the European honeybee. These buzzing little pollinators are crucial to keeping our planet green and flowering by carrying pollen from one plant to another. The nectar gathered is turned into honey in the colony. Four tiny wings flapping continuously cause their distinctive buzz. It is generally accepted that most European bee colonies are now hybridized African “Killer Bees.”

Killer bees originated in Africa where people to this day still live in harmony with them and few deaths are reported. They were accidentally released from a captive studied colony in Brazil and over several decades migrated up to the U.S. where they are taking over all the European colonies. Contrary to all the hype, doom and gloom, and scifi nothing much happened after they took over. A few people a year and a few more pets die, but not nearly as much as we thought. Use common sense when dealing with any bee colonies and always call an expert.

Another bee often seen in the Arizona desert is the bumblebee, which lives in colonies in the ground. The leaf cutter bee makes holes in rose and bougainvillea leaves, which normally doesn’t harm the plants. Carpenter bees sound aggressive since their flight is noisy but they rarely sting and are usually busy searching for holes in buildings in which to lay their eggs.

Far and away the most common bee in our area are “solitary bees.” They live in holes in the ground or in rotting plants and will almost never sting as they are the solitary provider for their brood and cannot afford to die uselessly and doom their offspring. Unfortunately we are currently experiencing a major crisis in that these bees are dying off in record numbers and we are unsure if this continues whether our carefully evolved Sonoran desert exosystem will survive with out our pollinators.

Wasps also drink nectar but they are predators as well. They use their stingers to paralyze insects and then lay their eggs on the bodies. When the larvae hatch they eat the victims. Most wasps live solitary lives although some, such as the paper wasp, form colonies. Their nests are made of chewed wood fiber, which they attach to buildings, usually under cover of eaves and roofs. Their sting is painful and when disturbed they will swarm and attack. They often see in the infra-red and can even sting at night if their nest is disturbed.

Yellow jackets also form colonies and enjoy sharing your food at picnics. They should be avoided since their sting is very painful. Hornets nest in hollow trees and are not as aggressive but also have a painful sting.

Ants have short life cycles but their strength is in the vast numbers they maintain in huge colonies. They are held up as the example of industriousness since they are constantly busy repairing their nests and searching for food to take back to their thousands of comrades. They gather seeds, dead insects, plant matter and food scraps.

The colony is made up of thousands of female workers and one queen. Males die after mating. Workers defend the nest, feed larvae, gather food, dig tunnels and take care of the queen and her eggs. A small heap of dirt marks the entrance to their underground nests.

Fire ants are found in the desert Southwest and have a painful bite. Termites are also part of the ant family and live in soil and wood in large colonies. They can cause unseen damage to wooden structures and a barrier between any wood and earth should be created to prevent them from entering buildings.

Grasshoppers and Crickets

Male grasshoppers and crickets both entertain us with their songs. The grasshopper has more of a buzz sound whereas the cricket’s chirp is higher pitched and more pleasing to the ear. The Field Cricket sings day and night from spring to fall. Crickets seen in the Southwest include the field cricket, house cricket and Jerusalem cricket.

Both crickets and grasshoppers have long hind legs for jumping and thin strong front wings. Their jaws are well adapted to chewing on plants. Locusts belong to the same family but are not normally found in this area.

Flies and Mosquitoes

No one likes those annoying two winged insects we call flies. Mosquitoes and gnats are also members of this group. Houseflies have the ability to hover like hummingbirds, can fly backward and react quickly to movement -- no wonder they are so hard to swat. Since their feet have claws and are sticky, they can walk vertically or upside down on any surface. The black fly black horse fly and deer fly are found in the Southwest and all have a painful bite.

Mosquitoes carry diseases that can be harmful to man and some animals. The female stabs the skin and sucks the blood of birds, mammals, reptiles and humans. The male feeds on nectar and plant juices. They can be controlled around the house by eliminating sources of standing, stagnant water where they deposit their eggs to hatch and mature.

They are not all bad since both flies and mosquitoes are foremost food sources for birds, fish and bats and they also pollinate flowers.

Cockroaches

We cannot talk about insects without mentioning that pervasive pest, the cockroach. Totally adaptable, it is now found all over the world. They can fly as well as run to escape into cracks where they stay hidden during the day. By night they scavenge for food and will eat almost anything. They are most commonly found in areas where people food is stored and prepared. It has been said that the cockroach will inherit the earth when every other animal has become extinct.

Arachnids

“Bug” lovers would be disappointed if we failed to mention the Arachnids, which many people consider to be insects. The Arachnids -- spiders, centipedes and scorpions are also arthropods but are not insects. They have two main body sections, eight legs and no antennae or wings.

The scorpion is the most primitive and possibly the oldest of all arachnids. The first non flying land creature may well have been a scorpion. Common Southwestern species include the giant desert hairy scorpion and the considerably smaller, but more venomous, bark scorpion (centruroides). Their sting can be very painful to people and they are known to frequent clothing, beds and footwear.

Favorite living quarters are under rocks and stones or in underground burrows. They have pincer-like front claws and a long curved tail tipped with a stinger. The female scorpion does not lay eggs but gives birth to live young, which she carries on her back for two weeks while they mature.

Scorpions are carnivorous, hunting insects, spiders and small mammals at night. Their stinger is used to kill prey and fend off other scorpions and enemies. They in turn fall prey to spiders, lizards, birds and snakes. There is no good way to totally rid oneself and household from scorpions.

The best way is to “bug-proof” all entries into your dwelling. Spraying via pesticides is actually quite a bad idea, although many pest companies disagree. Not only does spraying kill beneficial insects it also endangers pets, other wild animals, children, and the elderly. The long term effects of continued exposure to pesticides is just now starting to become known and the findings are not good. Many modern diseases have been linked to gradual pesticide poisoning (but not yet proven).

Tarantulas prefer to hunt at night and can be seen crossing roads in search of prey and mates. It is a large spider, growing up to over two inches in length. It will bite if provoked but is not fatal and would just like to be left undisturbed in its nocturnal wanderings. Consider yourself very lucky to have tarantulas around as they are one of the few spiders that eat black widows and brown recluse spiders which are far more dangerous to humans and companion pets. They may eat a dozen or more insects in one night. Males live maybe a dozen years and large females may be 25 to 30 years of age. They rarely stray more than 100 feet from their home in an entire lifetime except that the males go looking for a female once in their life. After mating the male will die and often becomes a meal for his queen to insure that his next generation of spiderlings get off to a good start.

Black widow female spiders however, have a poisonous bite that can be fatal. They are found in webs, usually in dark places, and will attack anything that approaches. They live in woodpiles, trash heaps, flowerpots and little used storage areas. The female is marked with a red hourglass pattern on her underside and is much larger than the male. Only the female bites.

We have learned to live with them and unless they come inside (where we relocate them back outdoors) we have had no problems. They usually only come out at night and some become so accustomed to us that they will take a cricket from our hands. Don’t do this unless you are a professional zoologist as the bite can be quite bad. But like all spiders they are pressure sensitive and rarely bite without pressure being applied to them.

There are many more insects out there and in the future we will srite on more of them. Try not to look at them as undesirable creatures as they are an intricate and necessary member of the web of life which makes us all one. In the mean time the Arizona Sonoran Desert Museum and the Sonoran Arthropod Study Institute located here in Tucson are valuable sources of more technical information. If you are bitten call the Arizona Poison Hotline or 911.