13 Types of Caterpillars in Florida: Which Ones Sting and Which Ones Are Safe

Florida’s warm, humid climate and year-round blooming host plants make it one of the richest caterpillar habitats in the country. Walk through any backyard garden, citrus grove, or oak hammock in the Sunshine State and there’s a good chance you’ll cross paths with one of dozens of caterpillar species, some destined to become beloved butterflies and others carrying a sting that rivals a wasp.

Knowing the difference matters. Some of the most common types of caterpillars in Florida are harmless garden visitors that gardeners actively encourage by planting parsley, milkweed, and citrus. Others are covered in spines connected to venom glands that can cause pain lasting for days. This guide walks through 13 caterpillars found throughout Florida, covering what they look like, what they eat, and whether they’re safe to handle.

Pro Tip: If you’re not 100% sure whether a caterpillar stings, the safest rule is to look but never touch. Use a stick or leaf to relocate it instead of your bare hands.

1. Monarch Caterpillar

The monarch caterpillar (Danaus plexippus) is arguably the most recognizable larva in North America, and Florida hosts monarchs year-round thanks to its mild winters. Monarch caterpillars love milkweed, and just like its butterfly form, the monarch caterpillar is among the most easily identified caterpillars in Florida, with a chubby body covered in yellow, black, and white stripes.

Because monarchs feed exclusively on milkweed species, gardeners across the country plant milkweed patches to support the population, from Florida dooryards to Wisconsin butterfly gardens along the migration corridor. Monarchs are completely harmless to handle, making them a favorite for classroom life-cycle projects and backyard butterfly gardening alike.

2. Long-Tailed Skipper Caterpillar

The long-tailed skipper (Urbanus proteus) thrives in Florida more than almost anywhere else in the country. Long-tailed skippers like it in Florida more than in other states, and one result of their love for the state’s warm climate is having two to three broods per year here, as opposed to a single brood elsewhere.

This species starts life as a green caterpillar with a brown head, and as it emerges into an adult it changes to brown and black colors, with wings mostly brown marked in yellow and black spots. Various types of beans and hog peanuts are among the host species of its caterpillars, which is why gardeners growing pole beans or lima beans often spot rolled leaf shelters where the larvae hide during the day.

The easiest, least disruptive way to manage long-tailed skipper populations in a vegetable garden is introducing predatory bugs like the Florida stink bug, a solution favored in organic farming. For a broader look at how caterpillars raise butterflies from egg to adult, the WFSU Ecology Blog’s raising guide walks through the entire process.

3. Black Swallowtail Caterpillar

The black swallowtail caterpillar (Papilio polyxenes) is one of the easiest caterpillars to invite into a Florida herb garden. Black swallowtail caterpillars eat plants in the carrot family, including many imported food plants gardeners already grow: fennel, dill, carrot greens, cilantro, and parsley, along with Queen Anne’s lace and rue.

Identification is straightforward: the caterpillar appears green with black and yellow bands running across each segment. Once grown, they transform into stunning black swallowtail butterflies, which help pollinate flowers throughout the garden. Gardeners in neighboring states report the same pattern, and the caterpillars found across Georgia feed on nearly identical host plants.

Because black swallowtails compete directly with humans for dill and parsley, many Florida gardeners plant a dedicated “sacrifice” patch. Dill, fennel, and parsley planted together attract black swallowtail caterpillars and keep them from feeding on other plants, according to Rockledge Gardens’ Central Florida guide.

4. Giant Swallowtail Caterpillar

Few caterpillars generate as much confusion among Florida homeowners as the giant swallowtail (Papilio cresphontes). The giant swallowtail is the largest butterfly in the United States, with a wingspan that can measure over six inches. Its caterpillar, however, looks nothing like its elegant adult form.

This most magnificent of butterflies has what is arguably the ugliest of caterpillars, one that grows quite large and needs extra protection from predators, relying on camouflage as its main defense. The larva adapts a mottled coloring that mimics bird droppings so it improves camouflage while sitting on its preferred host leaf, a trick that fools most backyard predators, including the many lizards found throughout Florida that hunt garden insects.

Because these caterpillars feed heavily on citrus trees, giant swallowtail caterpillars are known for their invasive profile on citrus, found on oranges all the time, which is why citrus growers sometimes call the larva the “orange dog.” Home gardeners with a single lemon or lime tree, though, usually have plenty to spare. Learn more about attracting this species in Birds and Blooms’ identification guide.

5. Spotted Apatelodes

The spotted apatelodes (Apatelodes torrefacta) regularly wins the title of Florida’s most photogenic caterpillar. Covered in downy fur with tufts of black hairs, it looks like a cuddly stuffed animal, and while it isn’t venomous, there are reports of people allergic to its hairs.

This species has a fuzzy coat with tiny patches of black fur, giving it an adorable plush-toy appearance, and its hue ranges from striking white to sunny yellow, with black, antenna-like bristles rising from its back. It is most active in late summer and uses many fruit trees as its host plant, so look for it in orchards and groves.

Because it’s generally safe to observe up close, the spotted apatelodes makes a good introduction for kids curious about raising caterpillars, similar to how enthusiasts explore other insects kept as pets. Even so, anyone with sensitive skin or known allergies should still handle it with gloves rather than bare hands.

6. Buck Moth Caterpillar

The buck moth caterpillar (Hemileuca maia) is one of Florida’s genuine stinging species, and it shows up predictably each year. In Florida, buck moth caterpillars are found on their two main host trees, willow and oak, and come in light and dark forms, with the common black-bodied dark form marked by small white dots; they are also toxic, with glands releasing toxins when their spines break off in the skin, and symptoms can last from a day to over a week, including redness, stinging, and swelling.

This large caterpillar, roughly 1¾ to 2¼ inches long when mature, is most often found on oaks and citrus, and in Florida there are two generations a year, one in spring and one in fall. The University of Florida IFAS Extension lists it among the state’s handful of genuinely venomous larvae.

Pro Tip: Buck moth caterpillars often drop from oak canopies onto sidewalks and driveways in large numbers during fall. Sweep them away with a broom rather than stepping on them barefoot.

Because buck moths favor the same oak-dominated understory found across the eastern half of the country, related stinging species also turn up among the caterpillars documented in Iowa.

7. Flannel Moth Caterpillar

Flannel moth caterpillars belong to the family Megalopygidae, and they’re some of the most deceptively dangerous larvae a Florida gardener can encounter. Many of these beautiful, adorably fuzzy caterpillars deliver the worst sting of any Florida species; it’s best not to touch fuzzy caterpillars like the flannel moth, since they’re part of a family known for dangerously venomous stings, and those who’ve been stung equate the pain to a bone fracture or an intense burning sensation.

The soft, hair-like covering hides stiff venomous spines underneath, which is exactly what makes this group so risky. Unlike smooth-bodied caterpillars that are almost always safe, any unusually fuzzy or fluffy-looking larva in Florida deserves a wide berth. Range maps show related flannel moth species reaching as far north as the caterpillar populations recorded in Maine, though Florida’s warm climate supports far larger numbers.

8. Hag Caterpillar

The hag caterpillar (Phobetron pithecium), also called the monkey slug, is built to confuse predators rather than fight them. It is a brown, fuzzy caterpillar with the strangest appearance in Florida, its flattened, furry body marked by nine pairs of unusual projections along the sides; the crawling creature might look like a dead hairy spider or an old leaf to hide from potential predators, and it can sting, with venom that causes pain if handled without protective gear.

That resemblance to a “dead hairy spider” isn’t accidental. Gardeners who spend time identifying the spiders found throughout Florida often mistake a hag caterpillar for one at first glance, since both share the same leggy, radiating silhouette. It’s one of the four major stinging caterpillars occurring in Florida, alongside the puss caterpillar, saddleback caterpillar, and io moth caterpillar.

9. Io Moth Caterpillar

The io moth caterpillar (Automeris io) is bright, sociable when young, and armed with a sting that surprises a lot of first-time gardeners. The io moth caterpillar is pale green, with yellow and reddish-to-maroon stripes running along its sides.

Young io moth caterpillars often feed in clusters before spreading out as they mature, covering a wide range of host plants including oak, willow, and other deciduous trees common across Florida landscaping. Like other stinging species, io moth caterpillars don’t possess true stingers but have spines connected to poison glands; some people experience a severe reaction requiring medical attention, while others feel only itching or burning. The Poison Center Tampa recommends first-aid steps if contact occurs.

Because io moths favor the same tree canopy that shelters many small reptiles, they’re frequently found sharing branches with the geckos common throughout Florida, which prey on smaller larvae before they reach the stinging stage.

10. Puss Caterpillar

The puss caterpillar (Megalopyge opercularis), sometimes called the asp caterpillar, is widely considered the most painful sting among Florida’s caterpillars despite its harmless, fuzzy appearance. It is stout-bodied, almost an inch long, and completely covered with gray-to-brown hairs; under the soft hairs are stiff, poisonous spines that break off in the skin when touched, causing severe pain.

The puss caterpillar’s name comes from its resemblance to a Persian cat, though some people call it the asp caterpillar because the sting feels similar to a snake bite. These caterpillars are prevalent throughout the southern United States, and experts recommend never touching them to avoid the severe pain caused by their poisonous spines.

Pro Tip: If stung by a puss caterpillar, apply tape to the area and peel it off repeatedly to remove embedded spines before icing the site. Seek medical care if symptoms worsen or spread.

Because they resemble small tufts of fur or debris on tree bark, puss caterpillars sometimes fool the same predators that keep watch for actual prey, including several chameleon species living in Florida that patrol oak and citrus canopies for insects.

11. Saddleback Caterpillar

The saddleback caterpillar (Acharia stimulea) is one of the easiest stinging species to identify by sight alone, thanks to its unmistakable pattern. It has a striking appearance: brown, with a wide green band around the middle of the body and a large brown spot in the center of that green band, giving the look of a brown saddle on a green blanket; the saddleback may exceed an inch in length and is stout-bodied.

The main poison spines sit on pairs of projections near the front and rear of the body, with a row of smaller stinging organs running along each side. Because the pattern is so distinct, it’s one of the few venomous species Florida parents teach children to recognize on sight, right alongside the stinging caterpillars documented in Maryland, where the same species also turns up on ornamental shrubs.

12. Spiny Oak-Slug Caterpillar

The spiny oak-slug caterpillar (Euclea delphinii) belongs to the same slug caterpillar family as the saddleback, and it shares that family’s flattened, gliding movement across leaf surfaces. Its body carries branching spines in shades of green, yellow, or orange, often edged in red, and those spines connect to venom glands capable of delivering a sting similar to its slug caterpillar relatives.

As the name suggests, it favors oak trees along with several other hardwoods common in Florida yards, feeding on the undersides of leaves where it’s easy to overlook until a hand brushes too close. It ranks among the lesser-known stinging species that occur in Florida alongside the puss, saddleback, io moth, and hag caterpillars. Gardeners raking leaves in fall should wear gloves, since spent larvae and old cocoons can still carry irritating spines.

13. Tussock Moth Caterpillar

Tussock moth caterpillars are a familiar spring nuisance across Florida oak canopies, and the fir tussock moth (Orgyia detrita) is by far the most abundant. Florida hosts three species of tussock moth: the fir tussock moth, the white-marked tussock moth, and the definite tussock moth, insects native to North America and particularly abundant in North Central Florida; the fir tussock moth is the most common, with the white-marked tussock moth a close second, while the definite tussock moth is very rare.

These colorful, hairy caterpillars hatch from eggs in late February or early March, and by early April they mature and disperse cocoons that are often left on homes, park benches, and other outside surfaces, hard to remove and containing hairs that can irritate the skin and cause an itchy, burning sensation.

For removal, the recommended method is walking around the house with a broom and sweeping the caterpillars into a pail of soapy water, then wearing a long-sleeved shirt to remove cocoons by slipping tweezers between the cocoon and the wall. The Florida Museum’s Thompson Earth Systems Institute has additional seasonal timing details for homeowners dealing with heavy infestations.

Important Note: This article is for general identification and educational purposes only, not medical advice. If you or someone else has a severe reaction after contact with a stinging caterpillar, including difficulty breathing, widespread swelling, or symptoms that worsen rather than improve, contact a physician or poison control center right away.

Living Alongside Florida’s Caterpillars

Most types of caterpillars in Florida are harmless, plant-specific larvae that reward patient gardeners with a butterfly a few weeks later. The exceptions, roughly half a dozen fuzzy or spiny species, are worth learning to spot on sight, since a little caution prevents most stings entirely.

The table below offers a quick-reference comparison for the species covered in this guide.

Caterpillar	Sting Risk	Typical Host Plants
Monarch	None	Milkweed
Long-Tailed Skipper	None	Beans, hog peanuts
Black Swallowtail	None	Parsley, dill, fennel
Giant Swallowtail	None	Citrus trees
Spotted Apatelodes	Low (allergy only)	Fruit trees, oak, maple
Buck Moth	High	Oak, willow
Flannel Moth	High	Various trees and shrubs
Hag Caterpillar	Moderate to High	Various hardwoods
Io Moth	Moderate to High	Oak, willow
Puss Caterpillar	Very High	Oak, citrus, elm
Saddleback	High	Various ornamentals and shrubs
Spiny Oak-Slug	Moderate	Oak and hardwoods
Tussock Moth	Low to Moderate	Oak

Whether it’s a monarch working its way through a milkweed patch or a puss caterpillar tucked against an oak trunk, learning to recognize these 13 species turns an ordinary backyard walk into a small identification exercise. For a broader look at caterpillar diversity beyond Florida’s borders, the general caterpillar identification guide and the wider roundup of insect types both make good next stops.