Wasp
The largest social wasp is the Asian giant hornet, at up to in length. The various tarantula hawk wasps are of a similar size and can overpower a spider many times its own weight, and move it to its burrow, with a sting that is excruciatingly painful to humans. The solitary giant scoliid, "Megascolia procer", with a wingspan of 11.5 cm, has subspecies in Sumatra and Java; it is a parasitoid of the Atlas beetle "Chalcosoma atlas". The female giant ichneumon wasp "Megarhyssa macrurus" is long including its very long but slender ovipositor which is used for boring into wood and inserting eggs. The smallest wasps are solitary chalcid wasps in the family Mymaridae, including the world's smallest known insect, "Dicopomorpha echmepterygis" (139 micrometres long) and "Kikiki huna" with a body length of only 158 micrometres, the smallest known flying insect.
Median wasp
The median wasp like many other species of wasps builds its nest out of pulp that comes from the digestion of wood. Their nests have been reported to be light yellow or light to dark grey in color depending on the material used to build the nest. These nests are about tall and wide with a thick roof. Mature nests have 2-4 circular or oval shaped combs that are surrounded by a thick envelope. There are two types of elements connecting combs. One is a rigid column down the center of the nest and the other is thin ribbon like pieces between the combs. Both are made of pulp and help to give the nest support. The entrance hole is at the bottom of the nest and often has spiraled sheets of paper surrounding it. The entrance of young nests sometimes consists of a long vestibule, or entry compartment, whose function is unknown. This long vestibule has only been observed in "D. media" and "D. maculata" species and tends to disappear as the nest matures. It may function in thermoregulation or defense. This species lives in cooler temperate climates and nests in the open so thermoregulation is a plausible explanation, but so far no other vestibule of this length have been observed in species that live in similar climates. A mature nest will house about 800 mature adults between May and October. Come October the males and workers being to die off and the queen hibernates until next spring when she will begin a new nest.