Top 15 Fascinating Facts About Beetles

1. Beetles Dominate Earth's Numbers

Beetles are the insect group with the largest number of known species. They are classified into the order Coleoptera (/ˌkoʊliˈɒptərə/; from the Greek κολεός, koleos meaning 'sheath' or 'case,' and πτερόν, pteron meaning 'wing'), comprising more described species than any other order in the animal kingdom, accounting for about 25% of all known life forms.

Approximately 40% of described insects are beetles (about 400,000 species), and new species are constantly being discovered.

Beetles are the largest group of organisms with the highest number of known species, making up about 1/4 of all known living organisms. Scientists have identified over 350,000 beetle species, but many more beetle species remain undiscovered. According to some estimates, there may be around 3 million beetle species on this planet. Furthermore, the order Coleoptera is the largest class within the animal kingdom.

2. General Identification of Beetles

Beetles are easily identifiable by their body shape and color. The body is oval to nearly round (2.8 – 5 mm long).

They have well-developed antennae and chewing mouthparts, as well as the front wings in the form of a hard shell called elytra. They often conceal their true wings beneath the hard shell and can only function when the elytra are fully open.

This elytra is waterproof, serving as a protective layer against injuries and water loss.

Unlike many other insects, beetles are generally not proficient flyers. They come in various colors, often black, with features like yellow and white scales on the head and wings.

Beetles exhibit diverse shapes, sizes, and colors. Some species, like the click beetle, have a long and slender body. Others, like ladybugs and June beetles, are oval or round. There are even beetles that resemble spiders.

Beetles belong to the insect order Coleoptera, which is the largest insect order with approximately 250,000 species worldwide, widely distributed. The larvae of beetles, causing significant damage to crops, let's learn more about this type of beetle.

According to entomologist Stephen Marshall, you can find beetles almost everywhere on the planet, from pole to pole. They inhabit both terrestrial and freshwater environments, from forests to grasslands, deserts to wetlands, and from seashores to high mountains.

You can even find beetles on some of the most remote islands in the world. British geneticist (and avowed atheist) J. B. S. Haldane suggested that God must have an infinite love for these beetles. Perhaps this explains why they are omnipresent in every nook and cranny on the globe we call Earth.

Some beetle species can become destructive insects with significant damage potential. Moth larvae, for instance, feed on natural fibers and feathers, often damaging wool and other fabrics. Others, like powderpost beetles, feed on hardwood and bamboo, attacking furniture and wooden items. Some species, such as flour beetles and grain beetles, invade household food supplies. They also damage food in production facilities and stores.

Some beetles damage lawns and landscapes. The larvae of June beetles attack grass roots. Leaf beetles, on the other hand, harm plants by feeding on leaves. Many beetle species are beneficial insects. Ladybugs (or lady beetles), for example, feed on harmful insects like aphids and scale insects.

However, beetles, including ladybugs and ground beetles, can become a nuisance. In late summer and fall, homeowners may find hundreds of individuals congregating outside the house. They are attempting to invade homes for winter shelter or to escape harsh conditions.

Beetle damage typically starts in April-May, with the most severe impact in September and October when their numbers peak. Beetle populations increase during the rainy season as young leaves provide abundant food. Temperature influences beetle abundance negatively.

Beetles undergo a life cycle comprising 4 stages: Egg - Larva - Pupa – Adult. Each time a female beetle lays eggs, it can deposit around 90 eggs. The life cycle of an individual beetle ranges from 30 to 60 days. Adult males typically live for about 13 days, while females live from 14 to 44 days.

However, the duration of the life cycle also depends on the available food for the larvae and environmental conditions.

Depending on the beetle species, some large beetles can develop rapidly, producing more than one generation per year. Yet, there are species like wood-boring beetles that may take several years to a decade to develop from eggs to mature beetles.

6. Common Types of Beetles in Vietnam

Hercules Beetle: The Hercules Beetle, a strongman among beetles, originated in South and Central America and is now found in Vietnam. People often raise them for competitions where they engage in battles to determine the winner. Hercules Beetles are mostly active at night, but occasional daytime activity is observed. True to their name, they exhibit incredible strength, able to carry loads over 850 times their body weight.

Chacosoma Three-horned Beetle: Listed as endangered in Vietnam with around 2000 species, this beetle is the largest in Southeast Asia. It has a shiny black or greenish color with three characteristic horns. Two horns grow from the thorax, while the third horn transforms from the head. Females, however, lack horns and have a mossy green color. Their thorax and wings are not smooth but have rough spots.

Coleoptera Beetle: Coleoptera, also known as the 'horned beetle,' is one of the most common beetle species in Vietnam. It comes in two colors, red and black, with black being more prevalent in Vietnam. These beetles are robust and possess a pair of large horns, with a lifespan ranging from 9 to 11 months.

Goliath Beetle: The Goliath Beetle, originating in tropical forests of Africa, is the heaviest beetle globally. Female Goliath Beetles have a V-shaped structure for digging and laying eggs, while males have a large horn on their heads for hunting and combat.

Whirligig Beetle: The Whirligig Beetle is characterized by its long, flat body and distinctive long antennae. This insect with wings is common in rural areas in Vietnam. The whirligig beetle has long, shiny wings, with five abdominal segments underneath. They have black eyes and a wide mouth. Both the front and rear thorax have parallel lines, and their color can vary to camouflage depending on the environmental conditions.

Stag Beetle: The Stag Beetle is well-known in Vietnam, belonging to the Lucanidae family. They have antennae with 10 segments, with the latter half larger. Stag beetles can be reddish-brown to black. Males have impressive mandibles, half the size of their body. Stag Beetles use these powerful jaws as formidable weapons to fight other males for territory.

7. Common Types of Beetles Worldwide

Turtle Beetle: A widely found beetle globally, often with a red or orange body and black spots. Some may have pink bodies with black patches. These beetles are small, ranging from round to oval, and usually have yellow wings. Research shows that female turtle beetles can lay from 20 to over 1000 eggs in about three months, protecting them near dung, inside tree trunks, and leaves.

Ground Beetle: Typically black and only 1-2 cm in size, also known as the black ground beetle. These beetles have a dark black color, with dark brown patches on their legs and antennae. Mostly harmless to humans as they do not bite. They prefer outdoor, damp places under rocks, leaves, and pieces of wood. If they invade indoors, they can cause damage, making cleanliness and dusting residential areas crucial for their elimination.

Tiger Beetle: Both the larval and adult forms of tiger beetles are carnivorous. They have slender bodies and long legs, with sizes ranging from 10 to 20mm. Large, protruding eyes enhance their vision. Tiger beetles exhibit peculiar colors such as orange, green, blue, and bright red. They are fast runners and can swiftly catch prey in seconds.

Leaf Beetle: These beetles have an oval body, short legs, and antennae half the length of their bodies. Generally, these creatures are less than 12 mm in total length. As the name suggests, leaf beetles enjoy consuming leaves and colorful flowers. Apart from being actual food sources, their leaf consumption habits can adversely affect environmental conditions. These insects have the ability to produce chemical toxins, serving as their primary defense mechanism. These toxins not only harm other carnivorous insects but also pose risks to humans. The toxins released from their mouths can immediately cause neurological diseases in humans.

Rhino Beetle: A heavy, oval-shaped insect with distinctive flat antennae resembling a club. Their front legs have teeth to help them dig and build their living environment. These insects enjoy consuming other insects and decaying plants or dung, while others feed on leaves, roots, and developing fungi.

Rose Beetle: As the name suggests, these beetles attack roses as their main food source. To protect your rose garden, use insecticides specifically designed to eliminate pests without compromising the beauty of these lovely flowers.

Dogbane Beetle: With a bright green color, dogbane beetles are among the most attractive beetles. Due to their small size, they can be easily overlooked. However, in an open field and suitable light, these shiny creatures can capture the viewer's attention. They have a green head while their wings are yellow, copper, and jade with small spots. Dogbane beetles feed on American or Indian hemp plants. Females lay eggs in their own dung, protecting them by attaching them to the underside of a leaf.

8. What Do Beetles Eat?

Beetles feed on plants, small insects, and animal carcasses (depending on the species). Some are considered garden pests, while others, like ladybugs, are beneficial to farmers.

Their favorite meals include smaller insects such as aphids, fireflies, and more. Additionally, they enjoy indulging in fruits like durian, rose leaves, and sweet-tasting fruits. While savoring their food, they extend their long proboscis, resembling a straw, to pierce into the meal. They extract all the nutrients, leaving nothing behind.

Particularly, beetles have a penchant for consuming carrageenan. In Western countries where fruits can be expensive, beetle enthusiasts often use carrageenan jelly to nurture these fascinating creatures.

In their natural habitat, beetles hunt for prey during the late afternoon to secure their meals. If kept as pets, it's advisable to feed them around 5 PM, varying their diet daily to ensure a diverse nutrition intake. However, it's crucial to maintain cleanliness in their food, free from spoilage, mold, and fruit flies.

Beetles have a pair of hardened wings covering their back, known as elytra, which protect the true wings underneath. Elytra close when they are at rest, revealing a distinct longitudinal line that separates the two wing portions. This symmetrical feature is characteristic of most members of the Coleoptera beetle family. During flight, beetles open their elytra to balance and use their membranous wings to move forward.

Parasitic beetles can live on other insects or even mammals. Some beetles are scavengers, feeding on decomposed organic matter or carrion. Dung beetles, for example, use dung both as food and a site for egg-laying. Beetles undergo complete metamorphosis with four stages: egg, larva, pupa, and adult. The time from egg to adulthood varies depending on the species.

While some beetle species mature rapidly, producing more than one generation per year, others like jewel beetles (Buprestid) may take several years to reach maturity. Environmental conditions play a significant role in their developmental time, with ideal conditions including factors like food, water, and temperature. Lack of these factors can impact their developmental timeline.

Many insect species are renowned for the sounds they produce. For example, cicadas, crickets, grasshoppers, and American katydids all sing their unique tunes. Numerous beetle species also create sounds, though not as melodious as their counterparts in the Orthoptera order. For instance, wood-boring beetles generate distinct 'creaking' sounds for extended hours...

Cicadas, also known as 'dry flies,' are a diverse group of large insects with prominent heads and wings with numerous veins. There are around 2,500 cicada species worldwide, inhabiting both temperate and tropical regions. Cicadas are most well-known for their large size, distinctive appearance with a large head, and the ability to produce vibrant, resonant sounds throughout the summer. In the Appalachian region, Americans refer to cicadas as 'dry flies' because their exoskeletons, shed after molting, remain intact and dry.

Cricket species occur in various environments, from grasslands, shrublands, and forests to marshes, beaches, and caves. Most crickets are nocturnal, and males produce loud, varied calls to attract females, though some species are mute. Interestingly, the echoing sound is not vocalized from the cricket's mouth but is generated through the friction between their wings. Adult crickets typically have two pairs of wings. The front wings are relatively stiff, serving to produce sound and protect the body, while the hind wings are soft and facilitate flight. When a male cricket chirps, the 'teeth' on the leading edge of the right front wing and the ridges on the left front wing continuously rub against each other, creating the sound.