s, which are a type of arthropod, are easily the most numerous group of multicellular organisms on the planet, with over a million species identified so far. The title of heaviest insect in the world has many rivals, the most frequently crowned of which is the larval stage of the goliath beetle, Goliathus goliatus, the top size of which is at least and. The largest confirmed weight of an adult insect is for a giant weta, Deinacrida heteracantha, although it is likely one of the elephant beetles, Megasoma elephas and Megasoma actaeon, or goliath beetles, both of which can commonly exceed and, can reach a higher weight. The longest insects are the stick insects, see below. Representatives of the extinct dragonfly-like orderMeganisoptera such as the CarboniferousMeganeura monyi and the PermianMeganeuropsis permiana are the largest insect species ever known. These creatures had a wingspan of some. Their maximum body mass is uncertain, with estimates varying between 34 g and 240 g.
Cockroaches (Blattodea)
The largest cockroach in length and wingspan is the South and Central American Megaloblatta, at up and respectively. Another contender for longest is Blaberus giganteus, which is found in the same general region and may reach a length of up to, depending on source. The heaviest is the Australian giant burrowing cockroach, which can attain a length of and a weight of.
Beetles (Coleoptera)
The beetles are the largest order of organisms on earth, with about 400,000 species so far identified. The most massive species belong to the genera Goliathus, Megasoma, Chalcosoma and Titanus. The longest species is the Hercules beetle, Dynastes hercules, with a maximum overall length of at least including the very long pronotal horn.
Earwigs (Dermaptera)
The largest of the earwigs is the Saint Helena earwig, which is up to in length. There are no recent records of this species and it is generally considered extinct. The largest certainly living species is the Australian giant earwig, which is about long.
True flies (Diptera)
The largest species of this huge order is Gauromydas heros, which can reach a length of and a wingspan of. The largest species of crane fly is Holorusia brobdignagius. It can attain about the same head-and-body length and wingspan, but if the legs are extended in front of and behind the body, then an overall length of makes it the longest true fly.
Mayflies (Ephemeroptera)
The largest mayflies are members of the genus Proboscidoplocia from Madagascar. These insects can reach a length of.
The largest species of this diverse, huge order are the giant water bugsLethocerus grandis and L. maximus. These can surpass a length of, although they are more slender and less heavy than most other insects of this size.
Ants, bees, and wasps (Hymenoptera)
The largest of the ants, and the heaviest species of the family, are the females of Dorylus helvolus, reaching a length of. The ant that averages the largest for the mean size of the whole colony is Dinoponera gigantea, averaging up to. Another ant that is native to Australia, Myrmecia brevinoda, workers are reported to be on average and queens are more than in length. The largest of the bee species, also in the order Hymenoptera, is Megachile pluto, the females of which can be long, with a 6.3-cm wingspan. The largest wasp is probably the so-called tarantula hawk species Pepsis pulszkyi, at up to long and wingspan, although many other Pepsis species approach a similar size. The giant scoliid waspMegascolia procer may rival the tarantula hawks in weight, if not length and wingspan, and queens of the Asian giant hornet can reach a body length exceeding 5 cm long with a wingspan.
Termites (Isoptera)
The largest of the termites is the African species Macrotermes bellicosus. The queen of this species can attain a length of and breadth of ; other adults, however, are about a third of this size.
The largest species is probably either the Queen Alexandra's birdwing, Ornithoptera alexandrae, a butterfly, or the Atlas moth, Attacus atlas. Both of these species can exceed a length of, a wingspan of and a weight of 12 g. Their larvae can weigh up to. However, the white witch, Thysania agrippina, has the longest recorded wingspan of the order, and indeed of any living insect, at up to, though it is exceeded in surface area and mass by both Ornithoptera and Attacus.
Praying mantises (Mantodea)
Giant shield mantids of the genus Rhombodera can reach lengths of nearly and are more robust than comparably sized mantids of other genera Some larger species have been known to capture and consume frogs, lizards, mice, small birds, and even snakes. Giant Stick Mantids of the genus Toxodera and Solygia can reach lengths of 20 cm, but are more gracile in build than other large mantids.
The largest living species of odonate is Megaloprepus caerulatus, attaining a size of as much as across the wings and a body length of over.
Grasshoppers, crickets, and relatives (Orthoptera)
Arachnacris katydids and Tropidacris grasshoppers reach up to in length and in wingspan, making them the largest by these measurements. The largest Saga and Pseudophyllus bush crickets are only are a few centimeters smaller. The heaviest of this widespread, varied complex of insects is the Little Barrier Island giant weta, Deinacrida heteracantha, of New Zealand; one specimen weighed and measured nearly.
Stick insects (Phasmatodea)
The longest known stick insects are also the longest known insects, but they are generally relatively lightweight because of their slender shape. The longest is Phryganistria chinensis where a specimen held at the Insect Museum of West China in Chengdu has a total length of. Other very large species, formerly believed to be longest but now considered second and third longest, are Phobaeticus chani and P. serratipes. A specimen of the former held in the Natural History Museum in London has a total length of and a specimen of the latter is. These measurements are, however, with the front legs fully extended. In P. chani, the body alone still measures. Another very large species is P. kirbyi where the total length is up to and the body alone up to.
Stoneflies (Plecoptera)
The largest species of stonefly is Pteronarcys californica, a species favored by fishermen as bait. This species can attain a length of and a wingspan of nearly.
Booklice (Psocoptera)
The largest of this order of very small insects is the barklouse of the genus Psocus, the top size of which is about.
Fleas (Siphonaptera)
The largest species of flea is Hystrichopsylla schefferi. This parasite, known exclusively from the fur of the mountain beaver, can reach a length of.
Thrips (Thysanoptera)
Members of the genus Phasmothrips are the largest thrips. The maximum size of these species is about.
Dobsonflies and relatives (Megaloptera)
Megaloptera includes dobsonflies, alderflies and relatives. The largest is the dobsonfly Acanthacorydalis fruhstorferi, which can have a wingspan of up to, making it the largest aquatic insect in the world by this measurement. This species is native to China and Vietnam, and its body can be up to long.
