Expect to see many types of caterpillars in Missouri throughout the year.
However, some caterpillars appear only at certain times of the year.
Depending on the season and other environmental factors, they may be more or less common than others.
You’re likely to come across nineteen types of caterpillars in Missouri.
1. Monarch Caterpillar
Monarch caterpillars are a type of caterpillar in Missouri that has orange and black features and distinctive white spots.
These caterpillars feed on milkweed plants and are highly poisonous. If you come across one, pick it up with gloves, not bare hands, and then place it back into a safe environment.
Keep an eye out for them, as they will be numerous! The monarch butterfly is known as a butterfly, but that’s a misnomer—they aren’t butterflies but members of their genus, Danaus. According to legend, King Danaus left Egypt after being persecuted by his sister’s husband.
2. Cabbageworm
The cabbageworm, a cabbage butterfly, is yellow with white stripes. It’s typically 2 inches long and an inch wide.
Caterpillars feed on cruciferous vegetables such as broccoli, Brussels sprouts, cabbage, and kale. Cat caterpillars leave their host plant and form pupal cocoons on or near it when fully grown.
As adults, they live two to three weeks, mate, and lay eggs on plants such as cabbage and broccoli. The Females of this type of caterpillar in Missouri lay hundreds of eggs at a time.
When they hatch, the resulting larvae are ready to eat in your vegetable garden. They usually hatch around July or August and can quickly destroy entire plants if not controlled.
3. Woolly Bear
Woolly bear caterpillars (and their cousins, fuzzy-footed tussock moths) are one of those animals that seem equally terrifying and cute.
The myth is that they predict how long winter will be. If they’re fat, it’s going to be a long, cold winter; if they’re skinny, expect an early spring.
While these caterpillars aren’t common in Missouri, you can find them on forest floors throughout Appalachia.
If you see one crawling around your house or yard, don’t worry—they won’t sting or bite. These types of caterpillars in Missouri want to eat leaves like any other caterpillar!
4. Viceroy Caterpillar
These caterpillars in Missouri are challenging to spot because they look like monarch butterflies. You’ll need to look closely at their wings to tell them apart.
Viceroy caterpillars have thin black lines on their wing covers, while Monarch butterflies are fully black with just one orange spot.
To avoid getting stung:
- Take a picture and refer back when necessary.
- If you do get stung by accident, apply ice immediately.
- The pain should go away within minutes.
- If it doesn’t, consult your doctor.
5. Large Maple Spanworm
The Large Maple Spanworm is a butterfly that spends its early life as a caterpillar on trees. This black-and-white beauty has intricate blue and red markings, which help it hide from predators.
Interestingly, as many other species do, females lay eggs singly instead of clustering them together.
So when you spot one caterpillar, there’s a good chance that others are nearby! Garden enthusiasts can find these charming creatures in Red Maples, Silver Maples, and sometimes Sugar Maples.
These types of caterpillars in Missouri typically live for one season before transforming into butterflies and flying away.
6. Variegated Fritillary Caterpillar
The Variegated Fritillary is a beautiful yellow, orange, and black caterpillar. It is sometimes mistaken for a monarch caterpillar due to its similar color pattern. The Variegated Fritillary does not have large spikes on its body as other fritillaries do.
The spikes are much smaller and only located on its head. These types of caterpillars in Missouri feed on violets and larkspur.
It can also be found feeding on thistles, birches, willows, clovers, and various milkweed species.
7. Curve-Lined Owlet Moth Caterpillar
The caterpillar is brown, with a series of white or pale yellow dashes extending down its body and two pairs of blue spots on its head.
It feeds on Basswood, Oak, and White Elm trees (Ulmus Americana). These types of caterpillars in Missouri are found from May to October.
They tend to go through five instar stages before pupating into adults, and they are most commonly found in fields and meadows where these trees are present.
It can be seen from July to September. Its host plants include basswood, elm, oak, and other deciduous trees.
The moth has light gray wings with dark markings near the wingtips. The moths have a wingspan of 1-1/2 inches and fly during summer months at dusk or after dark.
They are attracted to light sources and flowers such as lilac (Syringa Vulgaris) and azaleas (Rhododendron spp.).
8. Hornworm
Hornworms are caterpillars in Missouri that eat leaves and can defoliate entire trees. Hornworm moths lay their eggs on the undersides of plant leaves, so it’s wise to check your garden for these insects.
If you find a hornworm, carefully pick it up (with gloves or tweezers) and release it somewhere else.
Throwing them in your trash is not recommended, as they can survive inside their cocoons and cause more damage later.
9. White-Marked Tussock Caterpillar
The adult form of this caterpillar is a brown, hairy moth with thin black lines and spots on its wings. The caterpillar—which you must watch out for—can grow up to five centimeters long.
This type of caterpillar in Missouri has a mottled brown body with white markings on its back, sides, and front.
It feeds on oak and elm trees during spring and fall. Some people who come into contact with it report an irritation similar to that caused by poison ivy.
10. Milkweed Tussock Caterpillar
The milkweed tussock caterpillars are a type of caterpillar in Missouri. Perhaps, it is best known for being one of two species that feed on milkweed plants.
The plant contains a natural chemical called cardiac glycoside, which slows down a caterpillar’s metabolism.
That chemical is so powerful that it can temporarily kill birds and other predators if they eat one! How does a caterpillar get through? As it turns out, their enzymes can turn cardiac glycoside into another compound called digoxin.
Because of those enzymes, they can safely munch away on as much milkweed as they want without suffering any ill effects.
11. Parsley Caterpillar
The Parsley Caterpillar (Osmeteria sp) is large and has green hair that stands up like a mohawk.
These caterpillars in Missouri feed on parsley, so they are commonly found on parsley plants. The larvae have black-and-white markings with orange legs and a row of spikes along their backs.
These look like little alligators and are super creepy! If you see one on your parsley plant, don’t pick it off; just let it eat away until it pupates.
12. Giant Leopard Moth Caterpillar
The 12-inch giant leopard moth caterpillar is one you will want to steer clear of. The giant leopard moth is a native type of caterpillars in Missouri and produces both males and females yearly.
Male leopard moths release their pheromones at night when they fly, so that’s another good reason not to hang around them.
Females are harmless but large enough that your heart will jump if you come across a giant leopard moth caterpillar.
They’re black with white spots and typically feed on leaves from ash, basswood, and other deciduous trees.
13. Banded Tussock Caterpillar
Banded Tussock caterpillars are expected to be found in much of southern and western North America.
These types of caterpillars in Missouri feed on many plants, including mallow, crotalaria, vervain, sweet peas, oak, and pear.
Adults are distinguished by their black and yellow banded bodies, green wings, and long antennae.
Black Tusks are also a variety of Banded Tussock caterpillars found in Louisiana. They feed on sugar cane and various kinds of grass, making them a pest for farmers. Fortunately, they don’t thrive in colder climates.
14. Eastern Tiger Swallowtail Caterpillar
The eastern tiger swallowtail is a type of caterpillar in Missouri, one of two species of butterfly found in the state.
Like many butterflies and moths, they have special glands that excrete nasty-tasting chemicals called cyanogenic glycosides.
They also use these toxins to defend themselves from predators (including other caterpillars). When disturbed, they release a chemical that smells like bitter almonds.
As with most types of caterpillars in Missouri, they are considered by some cultures to be a delicacy (Japan, for example).
However, eating them can be toxic because they contain tryptophan, which can cause nausea, vomiting, and possible nerve damage when ingested.
15. Spicebush Swallowtail Caterpillar
The Spicebush Swallowtail is an endangered butterfly that has seen a decline in its population due to loss of habitat.
The caterpillar form is black and yellow with blue and red spots, whereas its adult form is orange with black wings. Spicebush trees are also at risk, having been overharvested for their bark and leaves used as spices.
Because these caterpillars in Missouri only live for three weeks as caterpillars, efforts must be made for their survival.
16. Spotted Apatelodes Caterpillar
Also known as Apatelodes torrefacta, these caterpillars are green with black spots along their sides. The caterpillar can reach a length of about 1 inch long.
The spotted apatelodes caterpillar is one of those caterpillars in Missouri that have an odor resembling rotting flesh.
This characteristic doesn’t allow it to receive many butterfly enthusiasts or insect photographers interested in getting a close-up shot.
While most people avoid these butterflies and their stench, some people feel pity and have taken steps toward building habitats.
17. Cecropia Moth Caterpillar
Cecropia moths are large green caterpillars in Missouri with interesting life cycles. Adult Cecropia moths do not eat, but their larvae are voracious plant-eaters.
Tiny caterpillars emerge when they hatch from eggs and immediately begin eating and growing.
Larvae go through four molts (shedding skin) over a few weeks before turning into pupae. Shortly afterward, adult moths emerge and mate.
Caterpillars do not have any natural predators except birds, which will readily eat them on sight!
18. Monkey Slug
The small and slimy body of a Monkey Slug makes it one of the more unattractive varieties. But perhaps its most fascinating quality is that it has no face!
The lack of facial features leaves its open mouth as an opening on its head. It likes to live on plants, shrubs, and trees.
One way you may be able to spot a Monkey Slug is by finding a trail leading up somewhere high. Its bright yellow-orange body stands out among other types of caterpillars in Missouri.
19. Io Caterpillar
The Io caterpillars are the most common type of caterpillars in Missouri. It looks like a lengthier green vine with small orange markings and a few distinctive spikes on its back.
Their coloration makes them easy to spot against green foliage, and they only grow as long as six inches. Although they can be destructive pests, they’re not considered dangerous creatures.
Typically, all these caterpillars need is fresh plant material to tender new growth for eating. Make sure any gardener friends are careful about putting plants or seeds outside without checking if they’re safe!
