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.
Poecilopompilus algidus
"P. algidus" is 13–28 mm in length with females usually larger than males and in some areas it is a mainly black wasp with a red spot on the metasoma. However, the wasps of the genus "Poecilopompilus" may be Müllerian mimics of other wasps and that the variation in appearance of "P.algidus" over its range is due to it mimicking other sympatric wasps with painful stings, for example it resembles the paper wasps in the genus "Polistes" in the south, and thus be difficult to distinguish from its congener "Poecilopompilus interruptus", but in the northern part of its range, it mimics the spider wasps of the geuus "Anoplius". To identify the two species, the observer needs to examine the spines on the front tarsi of females and the inner margin of the eyes, "P. algidus" females have 3 strong spines and the species shows convergent inner eye margins, while "P. interruptus" shows four weak spines on the front tarsi in females and parallel inner eye margins.