Top 16 Most Fascinating Facts about Butterfly Larvae

Butterfly larvae are the larval stage of butterflies or moths. Caterpillars, woolly bears... various hairy caterpillar species all develop from larvae to mature caterpillars of nocturnal moths belonging to the Erebidae family. Caterpillars (or caterpillars) are present on many familiar tree species such as guava, banana, and mulberry... surrounded by toxic, itching hairs for unsuspecting victims who accidentally touch them. It is not by chance that dozens of caterpillars can be found on a single guava tree at once.

They are found in Japan, Taiwan, South Korea, China, and Vietnam. Both the larvae and mature caterpillars have toxic, itching, dizzying, nauseating... hairs on their bodies.

Butterfly larvae are not an independent group consisting of many representatives of the animal kingdom. These are the larvae of representatives of Lepidoptera. Answering the question of whether caterpillars are insects or not, we can firmly answer yes, because this is a certain stage of development of the larvae. Butterflies are actually distributed across the planet, especially in places with flowering vegetation. Insect sightings are very rare in cold latitudes, as well as in deserts and barren plateaus. There are not too many butterflies living in temperate climate zones.

During the larval stage, butterfly larvae must eat a lot to sustain themselves until the pupal and adult stages. Without suitable nutrition sources around, they may not have enough energy to complete their developmental lifecycle.

Nutritionally deprived larvae may reach adulthood but cannot produce eggs. They can consume an enormous amount during the few weeks of their lifecycle. Some species consume up to 27,000 times their body weight during this stage.

Oak leaves are the preferred food of most butterfly larvae. A large number of butterfly larvae and moths often settle on oak trees (about 500 individuals), so it is likely that butterfly larvae are also selective about oak leaves. Other favored foods for many butterfly larvae include cherry, willow, or apple trees.

The biology of butterfly larvae is highly complex and diverse. To identify the type of insect, you need to pay attention to its color, body size, number of legs, length and density of hair, nutritional characteristics, as well as other specific features. Depending on the species, the length of butterfly larvae ranges from a few mm to 12 cm. The body of the insect consists of: head, 3 thoracic segments, and 10 abdominal segments with legs located on them.

The head of the butterfly larvae consists of 6 fused segments, resulting in a compact capsule formed:

• The area between the eyes and forehead is called the forehead. At its bottom, there is a hole that resembles a heart in its configuration.
• For most insect species, a round shape is typical. However, some species have triangular, rectangular, or heart-shaped heads.
• Butterfly larvae, like other insect larvae, have a primitive brain. The parietal region may protrude significantly on the body surface, forming a kind of 'horn'.
• On the surface of the organs are small sensory antennae.
• Examining the structure of butterfly larvae, it can be seen that all insect species are distinguished by a chewing mouth apparatus. Their upper jaws are well developed, equipped with teeth allowing them to gnaw and tear food. There are chewing muscles inside the mouth cavity that insects use to chew food.
• The salivary glands are a specific spinner that allows the caterpillar to form a thread. The lower jaw and lips are fused into a single complex.

The larval stage is when butterfly larvae undergo significant size changes. Within a few weeks, their size increases exponentially. Butterfly larvae must molt several times to accommodate their new size, with most undergoing 5-6 molts before entering the pupal stage. It's no surprise they have to eat voraciously to stock up on energy for the pupal stage.

Researchers have identified a 'molting hormone' - responsible for triggering the molting process in larvae to transform into beautiful butterflies.

The research team also found that by manipulating their hormone therapy, they could halt the larval growth process. This discovery could provide better insights into hormone control over growth processes in humans.

David Champlin, a biology professor at the University of Southern Maine and co-author of this study, likened the newly discovered hormone (called metamorphosis initiation factor) to a starter motor in a car.

According to the research team, metamorphosis is regulated by the nutritional regime in the larvae's diet. By altering this diet, they can create bizarre creatures halfway between larvae and butterflies. For instance, hybrids with the mouthparts of larvae specialized for plant chewing and the proboscis tubes typical of butterflies. The development of antennae, legs, and eyes has also reached an intermediate stage.

Butterfly larvae's food is divided into 2 groups: common food and special food. The common food group includes various crop plants, while the special food is limited to a few plants.

For example, Mourning cloak butterfly larvae will eat willow, elm, birch, alder, cottonwood, and hackberry. Meanwhile, Black swallowtail butterfly larvae will eat any member of the parsley family: parsley, carrot, dill... Larvae specializing in one food group have smaller amounts of related plants. For example, monarch butterfly larvae only eat the leaves of milkweed plants.

A few butterfly larvae are carnivorous, often preying on soft-bodied insects like caterpillars. An unusual butterfly larva (Ceratophaga vicinella) found in the southeastern United States, feeds exclusively on the shells of deceased turtles. Turtle shells are made of keratin, making them difficult for this larva to digest.

6 small crescent-shaped openings are arranged along the head of the butterfly larva on each side. 1 out of 6 antennae is usually located near their mouth. You might think an insect with 12 eyes would have excellent vision, but that's not the case.

The eyes of butterfly larvae only help them distinguish between light and darkness. If you observe a butterfly larva, you'll notice that sometimes it moves its head from side to side. This is likely it assessing depth and distance because it navigates somewhat blindly.

Butterfly larvae rely heavily on muscles; even we humans only have 629 muscle segments in a much larger body than theirs. Just the head of a butterfly larva alone has 248 individual muscles and about 70 muscles controlling each segment. Notably, each of the 4,000 muscles is innervated by one or two nerve cells.

In most cases, when a butterfly larva hatches from its egg, it will consume the remaining portion of the shell. The shell and the outer layer of the egg, called the membrane, are rich in protein and provide the newly hatched larva with a nutritious start. After hatching from the egg, the butterfly larva will eat its own eggshell for nutrients. This is why we never see butterfly eggshells.

The egg is surrounded by a thin layer of wax on the outside called the membrane. This prevents water from evaporating before the larva has time to develop fully.

This stage in the egg lasts for several weeks until the egg hatches into a larva (butterfly). The first meal of a butterfly larva is indeed its own eggshell. It will then spend much of its time eating plant leaves.

Throughout its life, this species eats leaves and matures. To do this, it has a body like a bag and a mouth shaped like scissors to cut food. Most of them live on leaves and eat only one type of leaf. Their eyes and antennae are very small, so their perception is very poor.

Using modified salivary glands along both sides of their mouths, butterflies can produce silk when needed. Some butterflies, like the caterpillars of gypsy moths, create a silk 'balloon' for climbing trees.

Others, such as eastern tent caterpillars or silkworms, construct silk tents to live in. Bagworms use silk to attach dead leaves together to form a shelter. Butterflies also use silk when they pupate, helping them secure to a twig or to build a cocoon.

A butterfly cocoon is the outer casing of a butterfly pupa formed by silk threads produced by the mature caterpillar to withstand environmental conditions and natural enemies. The silk threads (simple threads) are threads that make up the cocoon, consisting of 2 small threads secreted from the pair of salivary glands of the mature caterpillar and stuck together, covered with a layer of adhesive. The main characteristics of silk: length of the simple thread and fineness of the silk. The silk thread can absorb moisture, be affected by hot water, acids, bases, metal salts, and dyeing agents.

The caterpillar's molting process into a resilient and enduring butterfly is arduous. However, when the butterfly emerges from its chrysalis with its beautiful wings, the previous struggles are perhaps all compensated.

The life cycle of a butterfly begins with the egg stage. Butterflies typically lay eggs on the leaves of plants that are their preferred food. The eggs are very small and have various shapes, but mainly spherical.

The stage within the egg lasts for a few weeks until the egg hatches into a larva (caterpillar). The first meal of the caterpillar is its own eggshell. After 2 - 3 weeks of hearty eating, larger caterpillars will spin silk into a structure we call a cocoon, into which they retreat, shed their skin, and transform into pupae.

A special sticky substance acts like glue, helping to keep the pupa firmly in place. The protective shell's color resembles a withered leaf, providing excellent camouflage. At this point, the pupa still relies on a hook at the tail end to cling tightly to the cocoon and prepares for the emergence process. After over 2 weeks, the butterfly inside curls up in the cocoon, creating a small hole to crawl out.

A newly emerged butterfly cannot fly immediately because its wings are not yet dry and firm. After about 1 hour, the butterfly's wings are fully sized, dry, and ready for flight.

Life at the bottom of the food chain poses many challenges, so caterpillars employ various strategies to avoid becoming an easy meal for birds.

Some species of caterpillars, such as those of the Black Swallowtail butterfly during their first molt, resemble bird droppings. Geometrid caterpillars mimic tree branches or scars on tree bark. Others use the opposite strategy, displaying bright body colors to warn potential predators of toxicity.

Some Spicebush Swallowtail caterpillars 'show off' their large eyespots to intimidate birds. If you've ever tried to pick up a caterpillar from a tree and it fell to the ground, you would notice it emits a foul odor as it secretes osmeterium for defense.

Additionally, caterpillars utilize their host plant's toxins as weapons. Some host plants produce toxic or foul-smelling compounds to deter herbivores from chewing their leaves. However, many caterpillars can use these compounds to protect themselves from predators. A classic example is the Monarch butterfly caterpillar and its host plant, the milkweed. Monarch caterpillars digest glycosides produced by milkweed plants. These toxins remain in their bodies until they mature, rendering the Monarch butterfly unpalatable to birds and other predators.

Caterpillars move with a predictable motion, with enough pseudo-legs to make their movement quite discernible. Typically, a caterpillar first anchors itself using the pair of pseudopods at the rear, then stretches forward with one pair of legs at a time, moving from back to front.

However, there's more than just leg action happening. The caterpillar's blood pressure changes as it moves forward, and its gut, essentially a floating cylinder inside the body, advances in sync with the head and tail ends. Longer caterpillars, with fewer pseudopods, move by pulling their rearward portion forward into contact with the thorax and then extending their front half.

Most caterpillars you've encountered have more than 6 legs, but most of those legs are pseudo-legs, called prolegs, which help the caterpillar grip onto plant surfaces and enable it to climb. The 3 pairs of legs on the caterpillar's thoracic segments are the actual legs, which will be retained into adulthood.

A caterpillar may have up to 5 pairs of prolegs on its abdomen, typically including a terminal pair at the rear.

The puss caterpillar, or southern flannel moth caterpillar, is an incredibly cute-looking creature that might tempt you to consider it as a pet at first glance. But beware, don't touch it. This insect, scientifically known as Megalopyge opercularis, is the larva of the southern flannel moth.

A 7-year-old boy from Mississippi, USA, was stung by one of these caterpillars and was quickly taken to the hospital. The boy had touched the caterpillar larvae in his home garden. He described the sting from this caterpillar species as potentially more painful than a jellyfish sting, or any other type of octopus or bee sting.

This caterpillar species has also been found in remote states like Missouri and Texas.

According to WebMD, it's the most venomous caterpillar in the United States, and its venom is contained within hollow spines found in its dense fur. Their diet includes oak, elm, and sumac leaves. They inhabit shaded tree canopies around homes, schools, parks, and more.

Many cases of puss caterpillar stings result in bone damage. The level of pain experienced by victims depends on the location of the sting and the number of spines embedded in the skin. While cow killer ant stings disappear within an hour, puss caterpillar stings on the hand can spread to the arm and last for 12 hours.

According to officials at Texas A&M, these caterpillars are most commonly found in late summer and early fall.

As spring weather brings fluctuating temperatures, caterpillars often choose to cluster together to maintain warmth. Like other animals, they huddle closely to avoid the wind. When temperatures drop too low, caterpillars create a sheltered cocoon to keep warm.

Spring, the season of caterpillar reproduction, also poses a nightmare for horse farms in many countries. Free-roaming horses may inadvertently ingest caterpillars, whose tiny toxic hairs can embed in the horses' intestines, affecting digestion and, in severe cases, leading to miscarriage in pregnant mares. In Kentucky, USA, a horse farm owner lost up to a third of their future foals when the mother horses ingested caterpillars.

The increase in caterpillar populations can be detrimental to crops. Every 9-16 years, caterpillar species reach peak reproduction, coinciding with a proliferation of flowers, crops, and vegetation being ravaged. Fortunately, the following year, natural regulatory mechanisms decrease the caterpillar population, restoring ecological balance.

However, these caterpillars have many enemies, especially birds, and they employ various strategies to evade their stronger foes. Some feed at night, while others camouflage themselves during the day to avoid detection. Some have bright colors or unpleasant odors. Others have thick shells and irritating hairs sticking to their throats.

Most caterpillars are large enough to be easily seen with the naked eye. You may notice many holes and tunnels on the leaves, indicating caterpillar infestation. When such signs are observed, check the underside of the leaves to find the caterpillars. Severe caterpillar damage to young plants can lead to their death. Therefore, regularly inspect your garden and eradicate caterpillar nests promptly.

Manual caterpillar control methods:

• Regular garden inspections: If caterpillars are found, remove them immediately.
• Use row covers for vegetable gardens: Prevent caterpillar infestation in vegetable gardens by using row covers. Row covers with mesh still provide sufficient air and sunlight for plants while isolating your garden from caterpillars.
• Plant aromatic herbs as companion plants: Plant strong-smelling herbs such as mint, lavender, and tansy to deter caterpillars and harmful insects from your vegetable garden.
• Practice crop rotation: Avoid planting the same crops in the same location for more than 5 years. Crop rotation disrupts the development cycle of harmful insects.
• Attract natural predators that feed on caterpillars to protect your vegetable garden.
• Avoid lighting lamps at night, as moths are easily attracted to light sources.

Mopane caterpillars may look terrifying but are a delicacy favored in South Africa, even pricier than lobsters. Mopane caterpillars are a specialty food among the people in Zimbabwe and South Africa. They are also known as Emperor Moth caterpillars due to their preference for Mopane tree leaves, which are their favorite food source.

On Amazon, dried Mopane caterpillars are sold for $0.6/g. That's about $600/kg (equivalent to 13.5 million Vietnamese dong). Despite the high price, many people still hunt for Emperor Moth caterpillars because they can be turned into nutritious meals. South Africans usually harvest Mopane caterpillars after storms. When the caterpillars reach maturity, they are often handpicked.

Before cooking, the brownish oil is squeezed out of the caterpillars, and then they are sun-dried. Dried Mopane caterpillars can be eaten directly. They have a flavor similar to salted French fries and are very crispy. However, most native people prefer frying this food with tomatoes, garlic, peanuts, chili, and onions.

South African Mopane caterpillars are said to contain three times more protein than beef. Additionally, they are rich in beneficial nutrients such as potassium, sodium, calcium, etc. These caterpillars are dried and packaged for sale in markets across Southern Africa.

The world of butterfly larvae is incredibly diverse, with myriad colors and forms. Their beauty can both attract mates and deceive predators, as hidden beneath their beauty lies toxic hairs harmful to both humans and carnivorous animals.

Sibine stimulea Caterpillar: The unique caterpillar resembling a slug is predominantly green, with a white circle bordered by purple dots in the middle of its back, resembling a saddle. Its spines and hairs can cause swelling, nausea, and rash for days upon contact. These can be found in gardens, fields, and forests, feeding on everything from garden plants to large trees and shrubs.

Tyria jacobaeae Caterpillar: Initially grayish-yellow, Tyria jacobaeae caterpillars mature into a light orange color with clusters of dark veins. They are voracious feeders and can devour any type of grass. When food is scarce or for no apparent reason, they may resort to cannibalism. Typically, Tyria jacobaeae caterpillars live in groups to cooperate against predators. As they age, they tend to engage in fights with each other.

Danaus plexippus (Linnaeus) Caterpillar: After hatching, the striped yellow, black, and white caterpillar's body flattens out to the point of being nearly invisible. This caterpillar has two pairs of black 'antennae,' one pair located near the head. It grows rapidly, feeding exclusively on milkweed leaves. When fully mature, the monarch butterfly measures about 5cm in length. Despite its beautiful appearance, it's highly toxic due to the glycosides in milkweed leaves it consumes. After metamorphosis, they become some of the most beautiful butterflies in the world.

Lymantria dispar Caterpillar: Appearing from May to mid-July, young Lymantria dispar caterpillars are black with numerous long, stiff hairs. As they grow, they develop up to 5 pairs of blue spots and 6 pairs of red spots on their backs, with some black hairs on their heads. Their hairs can cause skin inflammation and pain upon contact. To spread throughout the forest, they climb trees, release silk threads, and wait for the wind to carry them away. These caterpillars love to feed on tough leaves like oak, willow, and maple. Once they invade a forest, they can strip trees bare, spread disease, harm other insects, or even kill trees.

Ochrogaster lunifer Caterpillar: This is a truly dangerous caterpillar species. The toxin of Ochrogaster lunifer is potent enough to cause fatal bleeding in humans. Even their airborne hairs can cause rashes and respiratory problems. Ochrogaster lunifer has a dark brown color and long, soft hairs. They live in brown silk cocoons and come out to feed at night.