In Arizona, caterpillars are abundant. Caterpillars from Arizona are usually huge, worm-like creatures with cylindrical bodies. Black and yellow striped caterpillars, fat green larvae with dots or patterns, black spiky crawling insects, or black and orange hairy caterpillars are common Caterpillars found in Arizona. The southern flannel moth caterpillar and the crowned slug moth caterpillar are two types of stinging caterpillars found in Arizona.
It may be difficult to tell the difference between Arizona caterpillars. Caterpillars go through instars, which are growth periods. The crawling larvae may alter color, form, and look throughout these four or five stages. In addition, depending on their food source and surroundings, caterpillars acquire various characteristics.
The white-lined sphinx moth larva (Hyles lineata), for example, is a slender, yellowish-green insect with black stripes that lives in Arizona. The deep green or lime green larvae with black and yellow dots and an orange or black tail may be found in other locations, however.
This guide to Arizona caterpillars is intended to help you identify the most common caterpillars in your area. You can learn more about Arizona’s hairy, smooth-bodied, spiky, horned, stinging, and unusual caterpillars by reading descriptions and photos here.
How to Identify Caterpillars in Arizona
If the insect has smooth, hairy, or spiky body, any particular markings, and horns, it can be identified as an Arizona caterpillar species. The six front legs and eight prolegs on caterpillars are also helpful identifying features. Tufts of long pencil hairs or lashes can be found on some caterpillars.
The host plants where Arizona caterpillars feed may be used to identify certain types of caterpillars. The monarch caterpillar (Danaus plexippus) is a green and black striped caterpillar that only eats milkweed plants. Nonetheless, across the Grand Canyon State, you may encounter different deciduous bushes and trees infested with the Arizona white-lined sphinx caterpillar (Hyles lineata) and fuzzy banded woolly bear (Pyrrharctia isabella).
Types of Arizona Caterpillars (With Pictures)
Let’s take a closer look at the distinguishing characteristics of Arizona caterpillars in general.
White-Lined Sphinx Moth Caterpillar (Hyles lineata)
Depending on its development level, the white-lined sphinx caterpillar has several color variations, including lime-green and yellow-green stripes and markings. This caterpillar resembles a long, plump worm-like creature in Arizona. A little brownish head and a hairy horn-like tail distinguish the black and light-green larva. The length of this Arizona caterpillar is 2.7 in (70 mm).
During the monsoon season, Arizona is home to white-lined sphinx caterpillars. In years with considerable rainfall, these yellowish-green striped larvae may be seen in large groups. In gardens, swimming pools, hiking trails, and roadways, they may become a pest.
Although this fleshy protrusion isn’t a stinger, the striped caterpillar has a black-tipped orange or brown sharp-looking horn. Humans are not harmed by the white-lined sphinx caterpillar. The long green caterpillar becomes a lovely brown and pink moth after pupation.
Arizona caterpillar identification
In the Arizona landscape, the white-lined sphinx moth caterpillar is easily recognized. It has black stripes down its back and sides, as well as a lime-green or yellow-green tube-like body.
Two-Tailed Swallowtail Caterpillar (Papilio multicaudata)
Before pupation, the larva of Arizona’s state butterfly, the lovely two-tailed swallowtail, changes from green to orangy-red. The humped back and prominent eyespots on the head of the chubby caterpillar distinguish it. Small dots traveling across the caterpillar’s segments are also present. The caterpillar has a somewhat conical form.
When young, the two-tailed swallowtail caterpillar has a yellow face and is green with white markings. The green caterpillar resembles bird droppings during this period. The adult caterpillar, on the other hand, is a reddish color with a black rim behind its enlarged head before pupation.
The horn-like structure known as the osmeteria protruding from behind its head is an identifying feature of this fat worm-like insect. This occurs when the caterpillar senses danger, and it also emits a disagreeable odor.
Arizona caterpillar identification
The wide head and neck, small eyespots, and black and white collar behind the head distinguish the two-tailed swallowtail caterpillar. Before pupation, the caterpillar becomes bright green and then red-orange.
Cabbage Looper (Trichoplusia ni)
The cabbage looper is a common green caterpillar in Arizona and other southern states with a pale yellowish-green head and fine yellow bands dividing its segments. It can severely damage cabbage plants. In a looping pattern, the small green caterpillar arches its back and has an identifiable crawling pattern. The larva may be entirely green or paler with two broad white stripes along its sides.
Green cabbage loopers grow to be 1.2–1.5 inches (30–40 mm) before they pupate. Cabbage pests can bore into cabbage heads and chew through cabbage leaves. The cabbage looper is a native caterpillar in Florida and other southern states, and it is found throughout the United States.
Arizona caterpillar identification
The looping motion of the cabbage looper caterpillar as it crawls is its most noticeable characteristic. The little pale green caterpillar has faint yellowish stripes on its segments as well.
Cecropia Moth Caterpillar (Hyalophora cecropia)
One of the most striking caterpillars in Arizona is the Cecropia moth larva, which has yellow and blue nodules. Orange, yellow, and blue ball-like tubercles sitting on ridged segments are the distinguishing features of this bluish-green caterpillar. On its eight prolegs, it also has bluish tubercles.
Wider than the caterpillar’s rear end is the caterpillar’s head section. The caterpillar of the cecropia moth grows to be 4 inches long and 110 mm long. This peculiar-looking Arizona caterpillar changes from a spiky black caterpillar to yellowish-green, then blue-green with colorful tubercles throughout its instars.
Arizona caterpillar identification
The yellow, orange, blue, and occasionally red spiky protrusions on the cecropia moth caterpillar’s bluish green body differentiate it from other caterpillars.
Banded Woolly Bear Caterpillar (Pyrrharctia isabella)
Due to its black hairy body with a brown-orange band around its middle, the banded woolly bear larva is easily identified in Arizona. The spiky covering of this black and orange hairy caterpillar isn’t a stinging caterpillar, and it doesn’t make you itch. Its spiky, hooked hairs, on the other hand, may induce dermatitis in some individuals.
Just before pupation, the black and brown hairy caterpillar is around 2 inches (50 mm) long. The woolly bear’s distinguishing characteristic is how it rolls into a ball when confronted, in addition to its bronze-colored ring.
Arizona caterpillar identification
The hairy black and brown body of the banded woolly bear caterpillar makes it easy to identify.
Common Buckeye Caterpillar (Junonia coenia)
The common buckeye caterpillar is a black, spiky caterpillar with orange stripes and an orange head. It comes in a variety of hues. The species, on the other hand, comes in a variety of colors. Some have white stripes and brown markings, while others are smooth but covered in little white dots.
Some spiky black caterpillars lack stripes. With spiky, meaty tufts along their cylindrical bodies, the spiky black caterpillars are 1.5″ (40 mm) long. Plantain, foxglove, and petunias are among the foods that long slug-like spiny larvae feast on.
Arizona caterpillar identification
Because of its many black-branched spines, white or lime-green stripes, and orangey-brown markings, the common buckeye caterpillar is simple to spot.
Monarch Caterpillar (Danaus plexippus)
The monarch butterfly larva is a striped caterpillar with black, white, and yellow stripes along its body. It has yellow, white, and black stripes. The hairy horns at both ends of the striped abdomen of the huge black and white caterpillar are also meaty. In Arizona, the harmless monarch caterpillar grows to be around 1.7 inches (45 mm) long.
This Arizona caterpillar features two pairs of black fleshy horns, one long and the other short, aside from its striped look. The monarch caterpillar is poisonous to birds and predators because of its diet. The caterpillar’s body becomes poisoned by milkweed toxins, making other insects and birds avoid it because of its large, plump cylindrical shape.
Arizona caterpillar identification
Due to its distinctive black, yellow, and white stripes that run across its abdominal segments, the monarch butterfly is easy to identify.
Viceroy Caterpillar (Limenitis archippus)
The viceroy butterfly larva has spiky horns at the top of its head and a brown, orange, and white body. The abdomen of this caterpillar is marked with raised protrusions and dotted markings that distinguishes it from others. Viceroy caterpillars resemble bird droppings in some instars. The 0.6″ (15 mm) long orange-brown and white spiny hump caterpillar is an ugly viceroy. Willow and cottonwood trees are common places to find Viceroy caterpillars.
Arizona caterpillar identification
An orange-brown bumpy caterpillar with the appearance of bird droppings is known as the viceroy caterpillar.
Variegated Fritillary Caterpillar (Euptoieta Claudia)
The orange-red spiky body of the giant variegated fritillary butterfly larva is distinguished by numerous black and white lines. The thorax of the orange caterpillar is likewise marked with a pair of clubbed spines and rows of oval, bright white dots. A tube-like insect with a 3.5″ (90 mm) length, the huge orange and black variegated fritillary caterpillar is a tube-like insect.
Arizona caterpillar identification
The longitudinal white and black stripes on the tubular body of the variegated fritillary caterpillar are orange caterpillars.
Tobacco Hornworm (Manduca sexta)
The tobacco hornworm caterpillar is a big green insect with white diagonal stripes and black dots down its sides. It is also known as the goliath worm. A curled head and a rosy-pink curving horn-like tail distinguish this horned caterpillar from other types. The big caterpillar, which grows 2.7 inches (70 mm) long, is also known as the Carolina sphinx moth.
The tobacco hornworm caterpillar is similar to the tomato hornworm (Manduca quinquemaculata). The markings and size of the tobacco hornworm and tomato hornworm are different. The tomato hornworm has V-shaped patterns rather than diagonal ones, measuring 4″ (100 mm) in length.
White V-shaped markings on the tomato hornworm caterpillar
Arizona caterpillar identification
A pale green, cylindrical caterpillar with pale white and black lateral markings, the enormous tobacco hornworm is a rare sight.
Giant Swallowtail Caterpillar (Papilio cresphontes)
Bird droppings are what the enormous swallowtail caterpillar resembles. The larva of Arizona and North America’s biggest butterfly, the giant swallowtail, is depicted in these photographs with its red osmeteria. The larva of the nasty brown caterpillar looks like bird droppings due to its mottled white, black, and brown patterns.
The caterpillar is difficult to see on tree and shrub limbs due to this camouflage defense mechanism. The caterpillar is 2″ (50 mm) long and brown in color.
Arizona caterpillar identification
The brown caterpillar with its enlarged head is distinguished by its white and dark brown markings, which are also known as orange puppy or orange dog.
Polyphemus Moth Caterpillar (Antheraea polyphemus)
The polyphemus moth caterpillar is a rich green silkworm with crimson dots along its cigar-shaped body, which has red dots with fine spines. When immature, this fat green caterpillar resembles a tiny green stumpy caterpillar. When it feeds on birch, willow, hickory, and elm leaves, it becomes engorged and plump. The polyphemus caterpillar has neon-red spots on its body, which grows 3 to 4 inches (75 to 100 mm) long.
Arizona caterpillar identification
Due to the bands or red bumps around each segment of its bright green body, the polyphemus silk moth caterpillar is easy to spot.
Red Admiral Butterfly Caterpillar (Vanessa atalanta)
The red admiral caterpillar is a black caterpillar with fleshy black branched spines and tiny white dots on its brown body. During the majority of its instars, the spiky black caterpillar is thin. The caterpillar becomes dark brown with thin black jagged spines before pupation, growing 1″ (25 mm) long.
Arizona caterpillar identification
The red admiral caterpillar’s glossy black body is covered in rows of spiky ridges, which serve as a distinguishing characteristic.
Silver-Spotted Skipper Caterpillar (Epargyreus clarus)
The silver-spotted skipper caterpillar has a yellow body with thin green lines and a prominent spherical reddish brown head. It has a yellow body with fine green lines. Bright orange eye patches, a bright red throat, and red feet distinguish the striped, yellow caterpillar. The caterpillar is 2 inches (50 mm) long and is yellowish-green in color.
Arizona caterpillar identification
The striped plump yellow body with a globular reddish-brown head with two prominent orange markings distinguishes the silver-spotted skipper caterpillar.
Spotted Tussock Moth Caterpillar (Lophocampa maculata)
The hairy yellow and black hairs of the spotted tussock moth caterpillar give it a distinctive appearance, as does its yellow ring with a row of black dots. Yellow woolly bear is another name for the little fuzzy yellow-banded caterpillar. This 1.1-inch (30-centimeter) long insect is yellow and black. Poplar, willow, birch, oak, and maple trees are all being attacked by the black-spotted yellow tussock caterpillar.
Arizona caterpillar identification
A black and yellow hairy caterpillar with several long white lashes protruding from either end, the spotted tussock moth caterpillar is a sight to see.
Crowned Slug Caterpillar (Isa textula)
The crowned slug caterpillar has a flattened oval body covered in stinging spines and has stinging spines on its sides. The green stinging caterpillar has crimson or yellowish edges and two raised yellow lines on its back, in addition to the poisonous yellow spines.
A 0.6-inch (15 mm) long leaf caterpillar emerges from the little oval caterpillar. Because it might give you a nasty sting, it’s best to keep clear of this spine-covered green caterpillar.
Arizona caterpillar identification
Due to the yellow spiny protrusions surrounding its green oval body, the crowned slug caterpillar is easy to identify.
Western Tent Caterpillar (Malacosoma californicum)
The western tent caterpillar is a thin worm-like hairy larva with orange or black setae (hairs) that has a lengthy black and orange body. The tent-like web structures where hundreds of leaf-destroying insects dwell give the orange and black caterpillar its name. The caterpillars may reach a length of 2.5 inches (50 mm).
Arizona caterpillar identification
A striking orange stripe and wispy orange hairs cover the tube-like black body of the western tent caterpillar, which distinguishes it.
Black Swallowtail (Papilio polyxenes)
The black swallowtail larva has bands of yellow and black markings on its bright green body, and is distinguished by its black stripes and yellow patterns. Black bands with yellow dots run the length of each segment of the striped, green larva. This striped green caterpillar grows to be about 1.5 inches (40 mm) long before pupation.
The black and white immature swallowtail caterpillars are, however, black and white. A poisonous variety of crawling bug found in Arizona is the black swallowtail caterpillar. The larva produces poisons that make it hazardous to birds and predators, despite the fact that it is innocuous to people.
Arizona caterpillar identification
The black and yellow stripes on the body of the black swallowtail caterpillar indicate that it is a large green caterpillar.
Southern Flannel Moth Caterpillar (Megalopyge opercularis)
The hairy Southern flannel moth larva may be found practically anywhere in Arizona, with light brown hairs. The brown venomous caterpillar looks harmless at first glance. The soft hairs conceal the stinging spines on this little hairy caterpillar, despite being coated with lush hairs.
Between 1″ and 1.5″ (25 to 38 mm) long, this stinging caterpillar The caterpillar of the southern flannel moth thrives in heat and arid conditions, which is why it is commonly seen in Texas and Arizona. Fire caterpillar, puss moth, tree asp, and woolly slug are some of the other names for this unusual stinging insect.
Arizona caterpillar identification
With its curly golden brown disheveled hairs covering a teardrop-shaped body, the southern flannel moth caterpillar has a unique look.
Yellownecked Caterpillar (Datana ministra)
The orange-throated moth larva has black and yellow stripes on its hairy body and a bulbous black head. It has black and yellow stripes on its hairy body. The spiky Arizona caterpillar has fuzzy look to it due to its silky spines. The cylindrical body of this yellow and black hairy caterpillar is 1″ (50 mm) long.
Arizona caterpillar identification
The yellow stripes down the length of a yellow-necked caterpillar’s body, from head to tail, are its identifying features.