Wasp
Wasps first appeared in the fossil record in the Jurassic, and diversified into many surviving superfamilies by the Cretaceous. They are a successful and diverse group of insects with tens of thousands of described species; wasps have spread to all parts of the world except for the polar regions. The largest social wasp is the Asian giant hornet, at up to in length; among the largest solitary wasps is a group of species known as tarantula hawks, along with the giant scoliid of Indonesia ("Megascolia procer"). The smallest wasps are solitary chalcid wasps in the family Mymaridae, including the world's smallest known insect, with a body length of only , and the smallest known flying insect, only long.
List of largest insects
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 wasp "Megascolia procer" may rival the tarantula hawks in weight, if not length and wingspan, and the Asian giant hornet "Vespa mandarinia" can reach a body length of up to 2 in.