The largest insects on Earth – preparing such a list is not an easy task. Because, how can you identify the “large”? It is a relative term: if you mean the “bulkiest” by largest, for instance, this title may go to the Goliath beetle (Goliathus), which are among the largest insects on Earth, if measured in terms of size, bulk, and weight. They measure from 60-110 millimeters (2.4-4.3 in) for males and 50-80 millimeters (2.0-3.1 in) for females, as adults, and can reach weights of up to 80-100 grams (2.8-3.5 oz) in the larval stage, though the adults are only about half this weight.

Or maybe Actaeon beetle (Megasoma actaeon) claims the title, which is a rhinoceros beetle, a member of the Scarabaeidae family. They can be up to 7 centimeters (2.8 in) across, with a body length of up to 13.5 cm (5.4 in) long by 4 cm (1.6 in) thick.

If you are looking for the “heaviest”, check out the Giant Weta, the heaviest insect in the world. A female giant weta filled with eggs can reach up to 70 grams!

The Giant Weta often cited as the heaviest insect on Earth. Large species can be up to 10 cm (4 in) not inclusive of legs and antennae. One captive female reached a mass of about 70 g (2.5 oz.), making it one of the heaviest documented insects in the world. But, usually, their body mass no more than 35 grams.

The largest wingspans? Then the title goes to the Queen Alexandra’s birdwing, is the largest butterfly in the world, with females reaching wingspans up to 1 foot (30 cm) wide.

The longest? In May 2016, it was reported that Phryganistria chinensis Zhao, discovered in Liuzhou, China, in 2014, was the world’s longest known insect at 62.4 centimeters (24.6 in). According to Wikipedia, the rare titan beetle (Titanus giganteus) from northeastern South America is often considered the largest insect, with a maximum known body length of just over 16.7 cm (6.6 in). But, even if you don’t count the legs, Phryganistria still measures an impressive 357 mm (14.1 in), way longer than the “titan”. But it’s very thin, so not as impressive as the titan beetle.

I decided to make my list by the overall length, including extensions like horns, antennae, etc. Here are the top ten largest insects on Earth.

List of Largest insects on Earth

By total body length:

10. Giant Water Bug (Belostomatidae): up to 12 cm (4.7 in)

The largest insects: Giant Water Bug (Belostomatidae) Photo: Frank Vassen, Wikipedia

Giant Water Bug (Belostomatidae) is a family of freshwater hemipteran insects. They are colloquially known as toe-biters, Indian toe-biters, electric-light bugs, alligator ticks, or alligator fleas (in Florida, US). They are the largest insects in the order Hemiptera, and occur worldwide, with most of the species in North America, South America, Northern Australia, and East Asia. They are typically encountered in freshwater streams and ponds. Most species are relatively large, typically at least 0.75 in (2 cm) long, although smaller species also exist. The largest are members of the genus Lethocerus, which can exceed 4.75 in (12 cm) and nearly reach the length of some of the larger beetles in the world. Giant water bugs are popular food in parts of southeast Asia.

9. Elephant beetle (Megasoma elephas): up to 13 cm (5.1 in)

The largest insects: Elephant beetle (Megasoma elephas). From the profile, an elephant beetle really looks like an elephant.

Elephant beetle (Megasoma elephas) is a rhinoceros beetle belonging to the Scarabaeidae family. The males can grow up to 13 cm (5.1 in), but females are 2-3 times smaller. They are actually black in color and covered with a coat of fine microscopic hairs. They are located in southern Mexico, Central America, and South American rainforests.

The largest insects: An elephant beetle from Costa Rica at the San Antonio Zoo’s Wild Wonders exhibit. Photo: mysanantonio.com

8. Atlas beetle (Chalcosoma atlas): up to 13 cm (5.1 in)

The largest insects: Atlas beetle (Chalcosoma atlas)

The Atlas beetle (Chalcosoma atlas) is a species of rhinoceros beetle (Scarabaeidae family). It is named after Atlas, a Titan condemned to hold up the sky for eternity in Greek mythology. The males are larger than the females, reaching a length of up to 13 centimeters (5.1 in).

The larva of the Atlas beetle is known for its fierce behavior, including biting if touched. Unverified reports exist of larvae that live together fighting to the death if there’s not enough space or food.

Atlas beetle lives in southern Asia, especially Indonesia.

7. Actaeon beetle (Megasoma actaeon): up to 13.5 cm (5.3 in)

The largest insects: Actaeon beetle (Megasoma actaeon) is one of the largest of all beetles.

Actaeon beetle (Megasoma actaeon) is also a rhinoceros beetle belonging to the Scarabaeidae family. It named after Actaeon, a famous Theban hero in Greek mythology. As mentioned above, with a large, bulky body, it is one of the largest of all beetles, measuring up to 7 centimeters (2.8 in) across, with a body length of about 5–12 centimeters (2.0-4.7 in). The males can grow to be 13.5 cm (5.4 in) long by 4 cm (1.6 in) thick. This species can be found in South America, particularly in Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Panama, Peru, Suriname, and Venezuela.

6. Enoplocerus armillatus: up to 15 cm (5.9 in)

The largest insects: Enoplocerus armillatus (giant longhorn beetle or imperious sawyer)

The females of the giant longhorn beetle reach a length of 70-80 millimeters (2.8-3.1 in) and males 110-120 millimeters (4.3-4.7 in), but specimens up to 150 millimeters (5.9 in) have been captured.

The giant longhorn beetle can be found in Argentina, Colombia, French Guiana, Guyana, Venezuela, Trinidad & Tobago, Ecuador, Peru, Brazil, Bolivia, Paraguay, Panama, and Suriname.

5. Titan beetle (Titanus giganteus): up to 16.7 cm (6.6 in)

The largest insects: Titan beetle (Titanus giganteus) is widely rated as the largest insect in the world.

Titan beetle (Titanus giganteus) is widely rated as the largest insect in the world. The largest reliable measured specimen was16.7 cm (6.6 in) in length. Several 18+ cm specimens are reputed/alleged to exist, though.

The titan beetle is comparable to such beetles as the Hercules beetle and the Macrodontia cervicornis. But the Hercules beetle males have an enormous horn on the pronotum or thorax making up around half of its total length. And also Macrodontia cervicornis’ length due to the enormous mandibles. As such, the body of the Titan beetle is considerably larger than that of the Hercules beetles and the Macrodontia cervicornis.

Titan beetle is one of the most mysterious creatures on Earth. It lives unobtrusively deep in some of South America’s hottest tropical rainforests of Venezuela, Colombia, Ecuador, Peru, the Guianas, and north-central Brazil, and only ventures out when seeking out mates. The larvae of this amazing insect have never been found.

4. Hercules beetle (Dynastes hercules): up to 17 cm (6.7 in)

The largest insects: Hercules beetle (Dynastes hercules)

The Hercules beetle (Dynastes hercules) is the most famous and the largest of the rhinoceros beetles. They can grow up to 17 cm (6.5 in), but as mentioned above, half of this length comes from the enormous horn.

Hercules beetle are highly sexually dimorphic, with the females generally being larger-bodied but much shorter, as they lack horns entirely, so much smaller by the overall length.

Anecdotal reports exist of the Hercules beetle being able to carry up to 850 times its body mass, but actual measurements on a much smaller (and relatively stronger: see square-cube law) species of rhinoceros beetle show a carrying capacity only up to 100 times their body mass, at which point they can barely move.

3. Macrodontia cervicornis: up to 17+ cm (6.7+ in)

The largest insects: Macrodontia cervicornis

Macrodontia cervicornis is one of the largest beetles, with known specimens exceeding 17 cm in length. Part of this length is due to the enormous mandibles, from which it derives both of the names in its binomen: Macrodontia means “long tooth”, and cervicornis means “deer antler”.

It is also known as the “Sabertooth Longhorn beetle”. Most of this species’ life is spent in the larval stage, which can last up to 10 years, and the larvae of M. cervicornis are extremely large, reaching up to 21 cm in length.

Macrodontia cervicornis is known from the rain forests of Colombia, Ecuador, Peru, Bolivia, the Guianas, and Brazil. Additional described species in the genus extend the overall range of the genus from Guatemala to Argentina.

2. Praying Mantis: Up to 18 cm (7 in)

The largest insects: Praying mantis

The world’s largest praying mantis was recorded at about 18 centimeters long, in Southern China, in 1929. According to Wikipedia, they can reach lengths of 20 cm.

As an apex carnivorous insect, the praying mantis feeds mainly on other insects. It is, however, documented that larger praying mantises are able to consume small reptiles and even small mammals or birds.

1. Phryganistria chinensis Zhao: 62.4 cm (24.6 in) – the largest insect on Earth.

Phryganistria chinensis Zhao, World’s longest insect

Until 2016, the longest insect in the world was Phobaeticus chani, a stick insect, with one specimen held in the Natural History Museum in London measuring 56.7 centimeters (22.3 in). Without legs fully extended, the body alone still measures an impressive 357 mm (14.1 in).

But, in 2016, a new species of stick insect in southern China has been declared the world’s longest bug: Phryganistria chinensis Zhao, at 62.4 cm (24.6 in). It is named after Zhao Li of the Insect Museum of West China, who spent years searching for the massive insect described by locals.

The insect returned with Zhao to the museum, where it laid 6 eggs. After hatching, even the smallest offspring cleared 26 centimeters.

The Largest Insect Ever Lived – Meganeuropsis permiana

The reconstruction of Meganeuropsis permiana, the largest insect ever lived. Photo: leandrosanchesarte.blogspot.com

Meganeuropsis is an extinct genus of griffinfly, order Meganisoptera, known from the Early Permian (299-272 million years ago) of North America, and represents the biggest known insect of all time. The genus includes two described species:

Meganeuropsis permiana described in 1937 from Elmo, Kansas. It was one of the largest known insects that ever lived, with a reconstructed wing length of 330 millimeters (13 in), an estimated wingspan of up to 710 millimeters (28 in), and a body length from head to tail of almost 43 centimeters (17 in).

Meganeuropsis americana , discovered in Oklahoma in 1940, is most probably a junior synonym of Meganeuropsis permiana . It is represented by a forewing fragment 28 centimeters (11 in) long, which is conserved and displayed in the Harvard Museum of Natural History; the complete reconstructed wing had an estimated total length of 30.5 centimeters (12.0 in), making it the largest insect wing ever found (with a resulting wingspan of 69 centimeters /27 in).

Honorable mentions

Goliath beetle (Goliathus): up to 11 cm (4.3 in)

One of the largest insects on Earth with a heavy, bulky body, the Goliath beetles are members of subfamily Cetoniinae, within the family Scarabaeidae. Goliath beetles measure from 60–110 millimetres (2.4–4.3 in) for males and 50–80 millimetres (2.0–3.1 in) for females, as adults, and can reach weights of up to 80–100 grams (2.8–3.5 oz) in the larval stage, though the adults are only about half this weight.

The name explains itself: named after the biblical giant Goliath, the Goliath beetle (Goliathus) are often rated as the biggest insects in the world, because they are really bulky. As explained above, the males can grow up to 11 cm (4.3 in) in length.

They can be found in many of Africa’s tropical forests, where they feed primarily on tree sap and fruit. Little appears to be known of the larval cycle in the wild, but in captivity, Goliathus beetles have been successfully reared from egg to adult using protein-rich foods such as commercial cat and dog food.

The females range from a dark brown to silky white, but the males are normally brown/white/black or black/white.

One of the largest insects on Earth, the Goliath beetle, like almost all other beetles, possess a reinforced first pair of wings (called elytra) which act as protective covers for their second pair of wings and abdomen. Only the second pair of wings (which are large and membranous) are actually used for flying. When not in use, they are kept completely folded beneath the elytra. Each of the beetle’s legs ends in a pair of sharp claws, which provide a strong grip useful for climbing on tree trunks and branches. Males have a Y-shaped horn on the head which is used as a pry bar in battles with other males over feeding sites or mates. Females are without a horn, and instead, have a wedge-shaped head which assists in burrowing when they lay eggs.

The largest cockroach

In length and wingspan, the largest cockroach is the South and Central American Megaloblatta. Its length and wingspan are up to 9.7 cm (3.8 in) and 18.5-20 cm (7.3-7.9 in) respectively. It lives in South and Central America.

Another contender for the longest cockroach is Blaberus giganteus , which is found in the same general region with the Megaloblatta. Males reach lengths of up to 7.5 cm (3.0 in) and females 10 cm (3.9 in), although other sources list 9 cm (3.5 in) as the maximum length.

The heaviest is the Australian giant burrowing cockroach (Macropanesthia rhinoceros), also known as the rhinoceros cockroach and litterbug. They are native to Australia and can weigh up to 35 g (1.2 oz) and measure up to 8 cm (3.1 in) in length. Unlike some other cockroaches, they do not have wings and are not considered pests. It plays a vital part in the ecosystem by consuming dead leaves, eucalyptus in particular, and recycling other matter.

The largest fly: Gauromydas heros (7 cm / 2.8 in)

Native to Brazil, Bolivia, and Paraguay, Gauromydas heros can reach a length of 70 mm (1.3–2.8 in) and a wingspan of about 10 cm (3.9 in).

The largest butterfly: Queen Alexandra’s birdwing

Queen Alexandra’s birdwing (Ornithoptera alexandrae ) is the largest butterfly in the world, with females reaching wingspans slightly in excess of 25 cm (9.8 inches). This species is restricted to the forests of the Oro Province in eastern Papua New Guinea.

The largest moth: Atlas moth

Moths comprise a group of insects related to butterflies. With a wingspan measuring between 25-30 cm (9.8-11.8 in), the Atlas moth (Attacus atlas) is usually quoted as the largest moth on Earth. It is endemic to the forests of Asia.

However, there are two other candidates: the first one is the white witch (Thysania agrippina ) with one Brazilian specimen having had a wingspan of almost 30 cm (12 in). The second one is the Hercules moth (Coscinocera hercules ). It has a wingspan of 27 cm (11 in), making it the largest moth found in Australia, and its wings have the largest documented surface area (300 square centimeters) of any living insect.

Atlas moth compared to a human hand. Image: Wikipedia

The largest hornet: Asian Giant Hornet

The Asian giant hornet (Vespa mandarinia ), including the subspecies Japanese giant hornet (V. m. japonica), is the world’s largest hornet, native to temperate and tropical Eastern Asia. It has a body length of up to 45 mm (1.8 in), a wingspan around 75 mm (3.0 in), and a stinger with a length of 6 mm (0.24 in).

The largest wasps: Tarantula Hawk and Giant Scoliid Wasp

The giant scoliid wasp has a wingspan of 11.6 cm (4.57 in). It is a parasitoid of the Atlas beetle, paralyzing the beetle with its sting and lays its egg on it. The wasp then buries the beetle underground for the larvae to hatch with the hatched larvae feeding on the still-living host.

Similar to the giant scoliid wasp, the tarantula hawk hunts tarantulas. They use their sting to paralyze their prey before dragging it to a brood nest as living food; a single egg is laid on the prey, hatching to a larva which eats the still-living prey. They are up to 5 cm (2 in) long.

The largest spiders

Spiders are technically not insects. Unlike insects, spiders do not have antennae.

The largest spider by leg span is the giant huntsman spider (scientific name Heteropoda maxima), which can reach up to 1 ft (30 cm).

The heaviest spider is the Goliath birdeater (Theraphosa blondi ). It is the largest spider in the world by mass and size, but it is second to the giant huntsman spider by leg-span. “Bird-eating” definition derives from an early 18th-century copper engraving by the German-born naturalist and scientific illustrator Maria Sibylla Merian (2 April 1647 – 13 January 1717) that shows one eating a hummingbird. Despite the name, it rarely preys on birds. Its diet consists primarily of other large arthropods, worms, and amphibians.

They have a leg span of up to 28 cm (11 in), a body length of up to 11.9 cm (4.7 in) and can weigh up to 175 g (6.2 oz).

Notes

1. Square-cube law on Biomechanics

The square-cube law (or cube-square law) is a mathematical principle, applied in a variety of scientific fields, which describes the relationship between the volume and the area as a shape’s size increases or decreases. It was first described in 1638 by Galileo Galilei in his Two New Sciences as the “…ratio of two volumes is greater than the ratio of their surfaces.”

This principle states that, as a shape grows in size, its volume grows faster than its surface area. When applied to the real world this principle has many implications which are important in fields ranging from mechanical engineering to biomechanics. It helps explain phenomena including why large mammals like elephants have a harder time cooling themselves than small ones like mice, and why building taller and taller skyscrapers is increasingly difficult.

As was elucidated by the British-born Indian scientist J. B. S. Haldane (5 November 1892 – 1 December 1964), large animals do not look like small animals: an elephant cannot be mistaken for a mouse scaled up in size. This is due to allometric scaling: the bones of an elephant are necessarily proportionately much larger than the bones of a mouse, because they must carry proportionately higher weight.

To quote from Haldane’s seminal essay On Being the Right Size, “…consider a man 60 feet high… Giant Pope and Giant Pagan in the illustrated Pilgrim’s Progress… These monsters.. .weighed 1000 times as much as Christian. Every square inch of a giant bone had to support 10 times the weight borne by a square inch of human bone. As the human thigh-bone breaks under about 10 times the human weight, Pope and Pagan would have broken their thighs every time they took a step.” Consequently, most animals show allometric scaling with increased size, both among species and within a species. The giant creatures seen in monster movies (e.g., Godzilla or King Kong) are also unrealistic, as their sheer size would force them to collapse.

Sources