A
Species Profile

Asp Caterpillar

Megalopyge opercularis

Looks like fur-stings like fire.
Chase D'animulls/Shutterstock.com
puss caterpillar - Megalopyge opercularis -head shot with selected focus on the head and mouth parts, larval form of southern Flannel moth on oak leaves

At a Glance

Wild Species
Also Known As Southern flannel moth, flannel moth caterpillar
Diet Folivore
Activity Cathemeral
Lifespan 75 years
Status Not Evaluated
Did You Know?

Despite the nickname "asp," it's a moth larva (Southern flannel moth), not a true "asp" or a stinging ant/wasp.

Scientific Classification

The asp (puss) caterpillar is the larval stage of the Southern flannel moth. Despite its soft, fur-like appearance, it has hidden venomous spines that can deliver a painful sting to humans and other animals.

Kingdom
Animalia
Phylum
Arthropoda
Class
Insecta
Order
Lepidoptera
Family
Megalopygidae
Genus
Megalopyge
Species
opercularis

Distinguishing Features

  • Dense, ‘fur’ or flannel-like coat that hides spines
  • Teardrop/oval caterpillar shape, often with a tapered end
  • Color variable (often gray to tan/orange-brown)
  • Painful sting from concealed venomous spines (urticating/stinging hairs)

Physical Measurements

Length
1 in (1 in – 1 in)
Top Speed
0 mph
About 1 centimeter per second
Venomous

Appearance

Primary Colors
Secondary Colors
Skin Type Larval integument concealed beneath very dense, soft-looking setae ('flannel' coat). Venomous, stiff spines are hidden under the setal layer and can penetrate when the caterpillar is touched or pressed.
Distinctive Features
  • Larval stage of the Southern flannel moth (Megalopyge opercularis), not a true 'asp' (not a wasp).
  • Mature larva typically about 25-38 mm long (some individuals reported slightly larger), with a compact, teardrop/oval silhouette and no obvious exposed head from above.
  • Dense, fur-like setae form a uniform 'puss' or 'toupee' appearance; body segmentation is largely obscured compared with many other caterpillars.
  • Posterior end commonly shows a distinct tapered 'tail' or tuft; the larva often looks thicker anteriorly and tapered posteriorly.
  • Venom apparatus: rows/clusters of urticating (stinging) spines beneath the soft setae; spines are not obvious visually, which is a key ID hazard cue (soft-looking ≠ safe).
  • Movement/behavior that affects appearance in the field: slow-moving; often rests on leaves/twigs and may drop/fall from trees, so it can be encountered on trunks, understory plants, or the ground beneath host trees.
  • Regional context commonly used for ID: frequently encountered in the southeastern U.S. (notably Gulf Coast states), often on broadleaf trees/shrubs used as hosts (commonly reported on oaks, elms, and various ornamentals/citrus).
  • Megalopyge opercularis (asp or puss caterpillar) looks like a smooth, plush fur ball with a tapered tail tuft and few markings, unlike other fuzzy larvae with bold tufts or marked segments.

Sexual Dimorphism

Sexual dimorphism is expressed in the adult moth (Southern flannel moth) rather than in the larval 'asp/puss' caterpillar stage, where sex cannot be reliably distinguished by external appearance.

♂
  • Adult male typically smaller and more slender-bodied than the female.
  • Adult male usually has more strongly bipectinate (feathery) antennae typical of many moths.
♀
  • Adult female typically larger and more robust-bodied than the male.
  • Adult female often appears fuller/rounder in the abdomen when gravid and generally less 'feathered' antennae than males.

Did You Know?

Despite the nickname "asp," it's a moth larva (Southern flannel moth), not a true "asp" or a stinging ant/wasp.

Full-grown larvae are typically about 2.5-3.8 cm long; the teardrop/oval outline and "fur coat" are key ID cues.

The adult moth (Megalopyge opercularis) is small and fuzzy too, with a wingspan commonly about 2.5-3.8 cm (about 1-1.5 inches).

Its sting comes from hidden hollow spines beneath the soft setae; brushing it can embed spines and inject venom.

Eggs commonly hatch in about ~6-8 days under warm conditions; larvae often develop over ~5-6 weeks before pupating (timing varies with temperature/season).

In warm seasons the pupal stage can be as short as ~2-3 weeks, but many individuals overwinter in the cocoon and emerge the following season.

Outbreak years are common in the Gulf/South Atlantic states, where caterpillars drop from shade trees onto sidewalks, patios, and school grounds.

Unique Adaptations

  • Venom delivery system: retractable/hidden urticating spines under a plush layer of setae-soft appearance masks a strong defense.
  • "Fur" (dense setae) helps deter predators and can reduce desiccation and minor physical damage.
  • Teardrop body shape and variable color (gray to tan to reddish-brown) improve camouflage on bark, dead leaves, and lichen.
  • Cocoon architecture: the operculum-like exit and stiffened silk/hairs help protect the pupa and may reduce parasitism/predation.
  • Broad host-plant use (polyphagy) allows survival across mixed urban/suburban landscapes and many forest edges.

Interesting Behaviors

  • Feeds openly on leaves (a "leaf-chewer"), often resting on trunks/branches where it resembles a tuft of plant material.
  • When disturbed it may remain still (relying on camouflage) rather than fleeing, increasing accidental human contact.
  • Can drop or be dislodged from host trees (wind, rain, pruning), which is why stings often happen under shade trees.
  • Builds a tough silk cocoon that incorporates hairs/spines; the cocoon often has an "operculum" (a cap-like opening), reflected in the species name opercularis.
  • Seasonal activity peaks in late summer to fall in many parts of its U.S. range, matching when sting reports often rise.

Cultural Significance

In the southeastern United States, the Asp or Puss caterpillar (Megalopyge opercularis) is a common backyard hazard. Often in warnings and school lessons, its furry look and painful sting make it an important part of local outdoor life.

Myths & Legends

Naming lore in the U.S. South: the common name "asp" arose as a fearful comparison to a venomous serpent-an example of folk naming that treats its sting as "snake-like" in intensity.

"Puss caterpillar" is a long-running regional nickname tied to its kitten-soft appearance; this contrast (cute look, painful sting) features in many local cautionary stories told to children.

In parts of Texas and the Gulf states, yearly "puss caterpillar" (Megalopyge opercularis) seasons have been reported in newspapers and extension bulletins for decades, a local warning about autumn hazards under oaks and shade trees.

In the southeastern United States, extension offices and health agencies warn each season not to touch the asp (puss) caterpillar, because it can look like a harmless tuft of fur or cotton.

Conservation Status

NE Not Evaluated

Has not yet been evaluated against the criteria.

Population Unknown

Life Cycle

Birth 300 larvas
Lifespan 75 years

Lifespan

In the Wild
62–330 years
In Captivity
60–300 years

Reproduction

Mating System Data Deficient
Social Structure Solitary
Breeding Pattern Transient
Fertilization Internal Fertilization
Birth Type Internal_fertilization

Megalopyge opercularis (asp/puss caterpillar) reproduces sexually. Short-lived, nocturnal adults pair only briefly; females release pheromones, males find and copulate, transferring a spermatophore. Females lay eggs on host plants; no parental care. Mating system not well known.

Behavior & Ecology

Social Incidental aggregation Group: 1
Activity Cathemeral
Diet Folivore Oak (Quercus spp.) foliage
Seasonal Hibernates

Temperament

Non-aggressive; defensive only when contacted or pressed against skin (envenomation via concealed spines beneath setae)
Slow-moving and cryptic; relies on concealment and passive defense rather than pursuit or intimidation
Non-territorial toward conspecifics; no known dominance hierarchy or cooperative brood care
Highly noxious to many potential predators; defensive response is contact-mediated rather than an active attack (clinical/toxicology and extension summaries; e.g., UF/IFAS EENY-033; medical case literature on Megalopyge opercularis envenomation)

Communication

none documented No airborne sound production or calling behavior reported for larval or adult stages
chemical communication Adult mating likely mediated by female-produced sex pheromones as in most moths; specific pheromone chemistry for M. opercularis is not consistently published in primary literature-treat as inferred rather than species-quantified
tactile/contact chemoreception Larvae use antennal and mouthpart contact to assess substrate/host plant; interactions with conspecifics are incidental rather than signaling-based
defensive 'communication' is primarily aposematic-by-consequence: predators learn avoidance after contact with urticating/venomous spines; this is an effect on receivers rather than an intentional signal UF/IFAS EENY-033; toxicology/clinical summaries

Habitat

Biomes:
Temperate Forest Tropical Dry Forest Tropical Rainforest
Terrain:
Plains Hilly Coastal Riverine
Elevation: Up to 4921 ft 3 in

Ecological Role

Polyphagous leaf-chewing herbivore (folivore) on deciduous trees and shrubs; occasional localized defoliator; serves as a defended prey item and as a host resource for natural enemies (parasitoids/predators).

Transfers primary production (leaf biomass) into higher trophic levels (food-web energy flow) Provides host biomass for parasitoids and predators (supports natural-enemy communities) Herbivory can contribute to pruning/defoliation pressure that influences plant growth patterns and community dynamics

Diet Details

Other Foods:
Oak leaves Elm leaves Hackberry leaves Pecan leaves Citrus leaves Persimmon leaves Leaves of ornamental shrubs and small trees +1

Human Interaction

Domestication Status

Wild

Asp (puss) caterpillar (Megalopyge opercularis) is not domesticated and has no history of selective breeding. People meet it mainly by accident, from stings, or through pest control and medical treatment. Across Megalopygidae, larvae are wild and avoided because of venomous stinging hairs; none are kept as pets or livestock.

Danger Level

High
  • Painful envenomation on contact: venomous spines are hidden beneath dense setae ("fur"); stings can cause immediate intense burning pain and radiating pain up an extremity (well-documented in clinical/toxicology and extension reports).
  • Local effects reported: erythema, edema, wheal/flare reactions, and occasionally vesiculation; pain can persist for hours.
  • Systemic symptoms reported in some cases: headache, nausea/vomiting, abdominal pain, lymphadenopathy, fever, and malaise; rare severe reactions may require emergency care.
  • Ocular injury risk if spines contact the eye (foreign-body/irritant effects).
  • Risk is highest for children and for accidental contact (falling caterpillars from trees, contact with outdoor furniture, handling).
  • Across Megalopygidae (HUBS): multiple species have medically significant stinging larvae; human interactions commonly include outdoor exposure, schoolyard/playground incidents, and occupational exposure (landscaping/arborist work).

As a Pet

Not Suitable as Pet

Legality: Asp (Puss) caterpillar (Megalopyge opercularis) is usually not regulated as a pet in most U.S. places. Collecting on public land may need permits; moving them across states may be restricted. Keeping them is discouraged; their sting can cause serious harm.

Care Level: Expert Only

Purchase Cost: Up to $25
Lifetime Cost: $50 - $250

Economic Value

Uses:
Negative economic impact (medical treatment and lost work/school time from stings) Pest management costs (landscapes, shade trees, ornamental plantings) Education/outreach value (entomology, venomous caterpillars; usually via images/specimens rather than live handling) Ecological value (native moth biodiversity; part of local food webs)
Products:
  • No direct commercial products (no fiber, honey, wax, etc.)
  • Indirect services/markets: pest-control services; sale of preserved specimens for educational collections (varies by vendor and locality)

Relationships

Predators 4

Tachinid fly Tachinidae
Ichneumon wasps Ichneumonidae
Braconid wasp Braconidae
Predatory birds
Predatory birds Aves

Related Species 3

Black-waved flannel moth Megalopyge crispata Shared Genus
Flannel moth Megalopyge lanata Shared Genus
White flannel moth Megalopyge albicollis Shared Genus

Ecological Equivalents 5

Animals that fill a similar ecological role in their ecosystem

Saddleback caterpillar
Saddleback caterpillar Acharia stimulea Larval stage feeds on trees and shrubs and has stinging hairs. Like Megalopyge opercularis, it is a common stinging caterpillar in the southeastern U.S., often found on yard and ornamental plants and causing skin reactions noted in medical reports.
Io moth caterpillar Automeris io A gregarious-to-solitary foliage-feeding larva armed with stinging spines. It overlaps geographically and ecologically with M. opercularis on hardwoods and ornamentals and is frequently implicated in human sting incidents, as reported widely in North American medical entomology and extension summaries.
Buck moth caterpillar Hemileuca maia A hardwood-feeding, heavily spined caterpillar that can cause painful stings. Shares a predator-deterrence strategy—venomous/urticating spines—and occurs in similar oak-dominated habitats where M. opercularis larvae are also found on host foliage; oak association is commonly noted in extension keys.
Spiny oak-slug caterpillar Euclea delphinii A limacodid (slug) caterpillar with venomous spines. Occupies a similar niche as a generalist leaf-feeder on deciduous trees and is a frequent look-alike and sting comparator for Megalopyge opercularis in field and medical identifications.
Hag moth caterpillar Phobetron pithecium Also called the monkey slug. A medically important tree-feeding caterpillar on the same woody hosts as Megalopyge opercularis. It looks different (lappets versus the dense fur of M. opercularis) but is grouped with M. opercularis because both can sting people.

An asp caterpillar is a type of caterpillar that can be found in various regions of the world, including North America. They are known for their venomous spines, which can cause skin irritation and, in rare cases, more severe reactions such as anaphylaxis. Some species of asp caterpillars are also known for their bright colors and distinctive patterns. They typically feed on the leaves of trees and shrubs. Keep reading to learn more about these amazing creatures!

Five Fun Facts about Asp Caterpillars

  • Some species of asp caterpillars have venomous spines that can cause skin irritation and in rare cases more severe reactions, such as allergic reactions, when they come into contact with human skin.
  • The venom of some species of asp caterpillars is used in traditional medicine in some parts of the world.
  • The venomous spines of asp caterpillars do not deter many birds as they are not affected by the venom.
  • Some species of asp caterpillars have a symbiotic relationship with ants, in which the ants will protect the caterpillars from predators in exchange for sugars and amino acids secreted from the caterpillar’s dorsal nectary organ.
  • Some species of asp caterpillars, such as the Eastern tent caterpillar (Malacosoma americanum), are known to construct communal nests or tents made of silk, which they use to protect themselves from the elements and predators.

Scientific Name

The scientific name for the asp caterpillar varies depending on the specific species. Some examples include the puss caterpillar (Megalopyge opercularis) which is found in the Southeastern United States, the flannel moth caterpillar (Megalopyge lanata) which is found in the Southwestern United States and the Southern flannel moth caterpillar (Megalopyge pyxidifera) which is found in the Southeastern United States. These are the most commonly known asp caterpillars
Asp caterpillar is a common name for the caterpillars of several species of moths in the family Megalopygidae. The exact number of species within this family is not well established and is likely to change as new discoveries and taxonomic revisions are made. However, currently, the family Megalopygidae is considered to have around 15-20 species worldwide

Appearance

Asp caterpillars, also known as flannel moth caterpillars, have a distinctive appearance. They are typically fuzzy, with long, stiff spines or setae (singularly seta) covering their bodies.
Their coloration and patterning can vary depending on the species, but many have bright and contrasting colors, such as yellow, orange, white, and black, which can help them stand out and deter predators. Some species also have tufts of longer, hair-like setae on their heads and tails that can also be venomous. They typically range in size from 1 to 2 inches long, weighing less than 1 ounce.
Many species have venomous spines or setae on their bodies that can cause skin irritation, burning sensations, and in rare cases more severe reactions such as anaphylaxis. The venom is not harmful to humans, but the stinging sensation and irritation can be quite unpleasant. The venomous setae on their body can be easily brushed off when they come into contact with skin. It’s important to handle them carefully and avoid touching them if possible, or if handling them is necessary, wear gloves.

Asp Caterpillars of North America

Some species of asp caterpillars found in North America are:

  • The Southern flannel moth caterpillar (Megalopyge pyxidifera), is found in the Southeastern United States.
  • The Eastern tent caterpillar (Malacosoma americanum), is found in the Eastern United States and Canada.
  • The hickory tussock moth caterpillar (Lophocampa caryae) is found in the Eastern United States and Canada.
  • The white flannel moth (Norape ovina) is found throughout the United States
  • The crinkled or black-waved flannel moth (Lagoa crispata) is found throughout the Eastern United states
  • The yellow flannel moth (Lagoa pyxidifera) is found in the Eastern United States.
  • The puss caterpillar (Megalopyge opercularis) is found throughout the Southern United States
  • The flannel moth caterpillar (Megalopyge lanata)is founded in the Southeastern United States.
Caterpillar of the Southern flannel moth on oak leaf. The caterpillar is cover in light hairs with a rusty-orange strip dissecting the length of its body. It is on a green oak leaf.

The Southern flannel moth (Megalopyge pyxidifera), is found in the Southeastern United States.

Behavior

Asp caterpillars are solitary and are most active during the day. They feed on the leaves of trees and shrubs, and they are known to be voracious feeders. They can be found crawling on the ground, on tree trunks, and on branches.
When they feel threatened, they will curl up to protect themselves, while displaying the venomous spines on their body. This is a defensive tactic to deter predators.
When fully grown, they will spin cocoons and metamorphose into moths. The adult moths are typically nocturnal and have earthy coloration and small size. Their main role is to reproduce.
There are variations in the behavior of different species of asp caterpillars. Behavior is also influenced by the environment, temperature, availability of food, and other factors.

Asp caterpillars are not considered major pests. They are considered generalist feeders and have a broad range of host plants, which means that they can feed on many different types of trees and shrubs. They typically feed on the leaves of their host plants, which can cause some defoliation, but generally not enough to cause significant damage to the plant. However, in some cases when there is a high population density of asp caterpillars and the food resources are limited, they can cause some damage to the host plant, which can affect the ecosystem. Caterpillars are an important food source for many species of birds and other animals, and therefore play an important role in the ecosystem by providing food for predators

Habitat

Asp caterpillars are found in a variety of habitats depending on the specific species. Some are found in woodlands, while others are found in more open areas such as fields and gardens. They can be found throughout North America, as well as in other regions of the world.
Many species of asp caterpillars are associated with deciduous trees and shrubs, such as oak, hickory, elm, and cherry. They are typically found on the leaves of these plants, where they feed and grow. They also form their cocoons on the branches of the host tree or shrub, or on nearby structures, such as fences or buildings. The habitats of asp caterpillars vary depending on the stage of their life cycle, with caterpillars typically found on leaves while adult moths tend to be found on flowers or other nectar sources.

Diet

Asp caterpillars are generalist feeders, which means that they can feed on a wide range of host plants. Their diet typically consists of the leaves of trees and shrubs, depending on the specific species. Some common host plants include oak, hickory, elm, and cherry.
During the caterpillar stage, they feed voraciously and can consume large amounts of leaves, which can cause some defoliation. However, as mentioned earlier, it is generally not enough to cause significant damage to the host plant.
Once they become adult moths, they do not feed at all as they do not have functional mouths. They have vestigial mouths. Vestigial is defined as relatively unformed and not functional. Since they are unable to eat, they rely on energy stores from their larval stage. Those stores are readily depleted as they mate and lay eggs. They die soon thereafter. The diet of asp caterpillars can vary depending on the specific species and the availability of host plants in their environment. They are opportunistic feeders and will feed on whatever plants are readily available

Predators

Asp caterpillars have a variety of predators depending on the specific species and their environment. Some common predators include:

  • Birds: Many species of birds, such as warblers, vireos, and woodpeckers, will feed on asp caterpillars. The venomous spines of asp caterpillars do not deter many birds as they are not affected by the venom.
  • Wasps and hornets: Some species of wasps and hornets, such as paper wasps, yellow jackets, and hornets, will feed on asp caterpillars. They will sting the caterpillars to paralyze them and then carry them back to their nest to feed their young.
  • Insect-eating mammals: Some species of mammals, such as opossums, raccoons, skunks, and squirrels, will feed on asp caterpillars.
  • Parasitoid insects: Some species of parasitoid insects, such as ichneumonid wasps and braconid wasps, will lay their eggs on or in asp caterpillars, and the developing parasitoids will consume the caterpillar from the inside out.
  • Some species of spiders and beetles also feed on asp caterpillars.

The presence and effectiveness of predators will vary depending on the specific species and the environment.

Threats

Threats that Asp Caterpillars Face

Asp caterpillars, also known as flannel moth caterpillars, face a variety of threats depending on the specific species and their environment. Some common threats include:

  • Habitat loss: As with many other species, habitat loss is a major threat to asp caterpillars. The destruction of natural habitats, such as woodlands and fields, can reduce the availability of host plants and limit the populations of asp caterpillars.
  • Pesticides: The use of pesticides poses a threat to asp caterpillars. Pesticides can kill or harm the caterpillars directly, as well as the predators that feed on them.
  • Climate change: Climate change can also affect asp caterpillars by altering the timing of the seasons, which can disrupt the timing of their life cycle and affect their ability to find food and reproduce.
  • Competition: Competition for food and other resources can also be a threat to asp caterpillars. They may have to compete with other caterpillars and insects for food and other resources.
  • Disease: Some species of asp caterpillars may also be affected by diseases, such as fungal or viral infections, which can reduce their populations.

The threats to asp caterpillars vary depending on the specific species and the environment. Some species may be more or less affected by certain threats depending on factors such as population densities, availability of food, and natural competition

Threats that Asp Caterpillars Pose

Asp caterpillars pose threats to humans and other animals depending on the specific species and their environment. Some common threats include:

  • Venomous spines: Many species of asp caterpillars have venomous spines or setae on their bodies that can cause skin irritation, burning sensations, and in rare cases more severe reactions such as anaphylaxis, when they come into contact with human skin.
  • Defoliation: Asp caterpillars cause some defoliation of trees and shrubs, which affects the health of the host plants, leading to aesthetic damage to landscapes and gardens.
  • Allergic reactions: Some people may have an allergic reaction to the venom from the asp caterpillars’ spines. These reactions can range from mild to severe, and in rare cases, they can be life-threatening.
  • Ecological impact: Asp caterpillars can also have an impact on the ecosystem, as they are a food source for many species of birds and other animals. A significant reduction in their population could disrupt the food chain and have an impact on their predators.

The asp caterpillar poses relatively few threats compared to other species. They are not considered major pests.

Conservation Status

The conservation status of asp caterpillars varies depending on the specific species. Also, the term asp caterpillar is not a scientific name and there are different species with different conservation statuses.
Many species of asp caterpillars are not considered to be endangered or threatened, as they have a broad range of host plants and a wide distribution. They are also considered generalist feeders and are not dependent on any specific habitat, which allows them to adapt to different environments. However, some species may be affected by habitat loss, pesticide use, and other factors that can affect their populations. Conservation status changes over time as new information and research become available. Species are reevaluated and their status is updated accordingly.
If you are trying to identify a specific species, consulting with a local entomologist or university is recommended. They will be able to provide more specific information about the conservation status of a particular species.

Lifecycle

The lifecycle of asp caterpillars involves four stages: egg, larva (caterpillar), pupa, and adult. The exact lifecycle can vary depending on the specific species, but generally follows this pattern:
The adult moths lay eggs on the leaves and branches of host plants, such as oak, hickory, elm, and cherry. After a few days, the eggs hatch into tiny caterpillars, also known as larvae. The larvae begin feeding on the leaves of the host plant. They go through several stages of growth, molting their exoskeleton as they grow. These molts are called instars, and most caterpillars have 5 or 6. As they feed and grow, they become larger and develop the characteristic venomous spines that are associated with asp caterpillars.
Once they have reached maturity, the caterpillars will spin a cocoon, typically on the branches of the host tree or shrub, or on nearby structures. Inside the cocoon, they undergo metamorphosis and transform into pupae. After a few weeks, the pupae emerge as adult moths. Adult moths have a neutral, earth-tone coloration and are small in size. Their main role is reproduction. They typically live for a few weeks, during which they mate and lay eggs to begin the next generation.
The timing of the lifecycle can vary depending on the specific species and environmental conditions, such as temperature and food availability. Some asp caterpillars have one generation per year, while others have multiple generations.

Lifespan

The lifespan of asp caterpillars varies depending on the specific species and environmental conditions. The caterpillar stage is the longest stage of the life cycle, lasting from several weeks to several months. Once they have reached maturity, they will spin a cocoon and transform into pupae. The pupal stage typically lasts a few weeks, during which the caterpillar undergoes metamorphosis and transforms into an adult moth.
The adult moth stage is the shortest stage of the life cycle, lasting a few weeks at most. Adult moths do not feed. Instead, they rely on energy stores from their larval stage. As adult moths, their main role is to reproduce. They mate and lay eggs to begin the next generation. The timing of the lifecycle can vary depending on the specific species and environmental conditions, such as temperature and food availability.

Population

There is no specific population information for asp caterpillars as a group, as the term asp caterpillars is not a scientific name. Asp caterpillars refers to different species with different population sizes. Additionally, population estimates can vary depending on the specific species and location, and they can change over time due to a variety of factors such as habitat loss, pesticide use, and climate change.
Monitoring the population of asp caterpillars and other species is an ongoing process, requiring regular surveys. The population estimates can be affected by many factors such as weather, disease, and predation, which can lead to fluctuations in population numbers.

Up Next:

View all 328 animals that start with A

Sources

  1. Illinois.edu / Accessed January 25, 2023
  2. tamu.eud / Accessed January 25, 2023
  3. ufl.edu / Accessed January 25, 2023
  4. wikipedia.org / Accessed January 25, 2023
  5. sciencedirect.com / Accessed January 25, 2023
  6. biomedcentral.com / Accessed January 25, 2023
Kathryn Koehler

About the Author

Kathryn Koehler

Kathryn Koehler is a writer at A-Z-Animals where her focus is on unusual animals, places, and events. Kat has over 20 years of experience as a professional writer and educator. She holds a master's degree from Vanderbilt University. When she is not writing for A-Z-Animals, Kat enjoys puttering in her garden, baking deliciously healthful treats for her family, and playing with her two rescue mutts, Popcorn and Scooter. She resides in Tennessee.

Thank you for reading! Have some feedback for us?


Asp Caterpillar FAQs (Frequently Asked Questions)

Many species have venomous spines or setae on their bodies that can cause skin irritation, burning sensations, and in rare cases more severe reactions such as anaphylaxis. The venom is not harmful to humans, but the stinging sensation and irritation can be quite unpleasant. The venomous setae on their body can be easily brushed off when they come into contact with skin. It’s important to handle them carefully and avoid touching them if possible, or if handling them is necessary, wear gloves.