The largest insects that ever existed were dragonfly-like beetles of the extinct order Meganisoptera, sometimes referred to as raptor flies, that lived about 317 to 247 million years ago. Griffinfly wingspans could reach up to 28 inches, and their huge mandibles made them formidable predators. Although no insects have reached the size of massive raptor flies since the Paleozoic, there are still some types of insects that are nonetheless large enough to give even seasoned entomologists a good scare.
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The Amazon rainforest is home to many large beetles, but none of them can be compared in length to the titanium beetle (Titanus giganteus). This massive beetle can grow up to 6.6 inches long, making it the largest beetle in the world by size. While scientists have never found specimens of titanium beetle larvae, they have discovered boreholes in dead trees that they believe were created by these larvae. Based on the size of these boreholes, it is estimated that the larvae of titanium beetles can grow to be 2 inches wide and up to 1 foot long.
The titanium beetle also has mandibles that can easily cut a pencil in half and even tear into human flesh. Believe it or not, this bug is actually a draw for adventurous tourists, and many ecotourism agencies in South America advertise pictures of them in their brochures.
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The longest insects on the planet are members of the order Phasmatodea, commonly known as stick insects, who have evolved a bizarre shape to hide from predators among twigs, twigs, and foliage. Stick insects that resemble actual sticks can vary greatly in size depending on the species, but many of them are over 1 foot long.
The longest stick insects belong to the genus Phobaeticus, including species Phobaeticus serratipes and Phobaeticus chani, both of which can reach about 22 inches in length and which previously held the world records for the longest insect before being beaten by newly discovered species. Currently, according to the Guinness World Records, the world record is held for the longest insect of the species Phryganistria chinensis, discovered in China in 2016, with one specimen measuring 25.2 inches.
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Members of the genus Deinacrida, known as Riesenwētās, are enormous insects that are endemic to the island of New Zealand and are closely related to crickets. Giant wētās usually grow up to 4 inches long and weigh up to 1.2 ounces, about the weight of a sparrow. These massive beetles are among the heaviest insects on earth. A female specimen of the species Little Barrier Island giant wētā (Deinacrida heteracantha) was found to weigh 2.5 ounces, the heaviest adult insect ever observed.
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Members of the genus Goliathus beetles, commonly known as the Goliath beetles, are strong contenders for the world’s largest insect title because of their weight and bulk. These giant beetles are found all over Africa, and males of this genus can be over 4 inches long and over 2 ounces in weight. However, Goliath beetles are even more massive in their larval stage, weighing up to 3.5 ounces. This makes their larvae the heaviest insects on earth. While a 2.5-ounce giant wētā still holds the record for the heaviest adult insect, some entomologists believe that certain adult Goliath beetles in the wild could weigh over 2.5 ounces and break the record – but they have yet to be caught and weighed by scientists.
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The bird-sized atlas moth (Attacus atlas), which is widespread in the Malay archipelago, is considered the largest moth in the world. Atlas moths are so large that their cocoons are occasionally used as purses for pocket money in Asia. Their wings are among the largest on Earth, with a wingspan of up to 10 or 11 inches and a total area of about 25 square inches. Only the Hercules moth (Coscinocera hercules), whose wings can reach a surface area of 46 square inches, has a larger wing surface area than the Atlas moth, and only the white witch (Thysania agrippina), with a wingspan of up to 14 inches, has a longer wingspan. However, the size of the atlas moth still exceeds these two species when mass, wingspan, and surface area are taken into account. The larvae of this species are also enormous. Atlas caterpillars can reach nearly 5 inches in length and weigh up to 2 ounces.
Members of the wasp genera, Pepsis and Hemipepsis, known as Tarantula Hawks, are the largest wasps on earth and generally measure about 2 inches long. These giant wasps are so big and wild that they can hunt tarantulas, which they use as a food source for their massive larvae. A female tarantula falcon lays eggs in the tarantula’s belly while it is still alive, and its offspring will eat the spider alive after hatching.
The species Pepsis pulszkyi is the largest tarantula falcon and therefore the largest wasp in the world, reaching a length of up to 2.7 inches with a wingspan of 4.5 inches. Tarantula hawks are also known for their massive spines, which can reach over a quarter inch in length, and their stings are considered to be some of the most painful insect stings in the world. The pain caused by a sting of the tarantula hawk species Pepsis grossa is second only to that of the ball ant.
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Members of the Mydidae fly family, commonly known as Mydas flies, can vary in size. Many of them are among the largest flies in the world, reaching lengths of around 2.4 inches. A species of Mydas fly, Gauromydas Heros, is the largest species of fly on earth, growing 2.8 inches in length with a wingspan of 3.9 inches. Common house flies (Musca domestica), on the other hand, are generally only a quarter of an inch long and have a wingspan of about half an inch.
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The Hercules beetle (Dynastes hercules) is the longest species of beetle on earth and one of the largest flying insects in the world. The extreme lengths of Hercules beetle specimens are the result of their massive horns, found only on male beetles and used to fight other males in disputes over mates. A male Hercules beetle’s horn can be more than half its length, so they can reach lengths of up to 7 inches. A hornless Hercules beetle’s body ranges from about 2 inches to 3.3 inches in length. The species is also quite broad, with body widths anywhere from 1.1 to 1.7 inches.
Giant water bugs
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Most of the members of the Hemiptera insect order, known as the true beetles, are not particularly large and pale compared to stick insects or giant meadows. However, one family within this order, Belostomatidae, or giant water bugs, contains species that can approach the lengths of the largest beetles in the world. Also known as toe-biters and alligator ticks, these giant insects can grow up to 4.7 inches long. The largest water bugs belong to the genus Lethocerus, with the species Lethocerus grandis and Lethocerus maximus vying for the title of the largest.
Known as voracious predators in the streams and ponds they live in, giant water bugs can use their giant pincers to give off a painful bite and inject poisonous saliva into their prey. However, they are also eaten by humans and are considered a delicacy in South and Southeast Asia.
Queen Alexandra’s bird wings
Queen Alexandra’s bird wing (Ornithoptera alexandrae) is the largest butterfly in the world. The species was only found in remote regions of Papua New Guinea and was discovered in 1906. The first specimen found was removed with a shotgun. Females are slightly taller than males, with a wingspan of nearly 10 to 11 inches. Males tend to have wingspans that range from 6 to 8 inches. In addition, the body of a female Queen Alexandra’s bird wing can be just over 3 inches long.
The species is valued by butterfly collectors for its rarity and status as the largest butterfly in the world, and individual specimens can fetch several thousand dollars on the black market. While poaching poses a slight threat to the survival of this species, habitat destruction is an even greater threat as the forests where Queen Alexandra’s bird wings live are increasingly being cleared to make way for oil palm, cocoa and rubber plantations create IUCN to list the butterfly as endangered.