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.
Hemipepsis ustulata
Tarantula hawks exemplify evolutionary success in insect defense. Justin Schmidt, from personal communication with John Alcock, the world’s leading "H. ustulata" expert: “They are aposematic, brightly colored and odored, and have hard, closely fitting, smooth and slippery integumentary sclerites, live long, form defensive warning aggregations, and even have sharp and effective defensive leg spines.” Unquestionably, they are some of the best-defended insects on earth. The well-documented descriptions of battles between tarantula hawk and tarantula evidence their defensive strength. In the jaws of one of the largest and most powerful spiders on earth, the tarantula hawk still almost invariably escapes unharmed. During their violent encounters, one can often hear loud crunching or snapping sounds as the tarantula attempts to crush the wasp in its jaws. Not a single wasp death in 200 tarantula encounters was recorded by Petrunkevitch, and only one wasp injury was observed in William’s extensive field studies. Their strong, slippery integumentary armor allows the wasp to slip away unharmed.