Yellowjacket or yellow jacket is the common name in North America for predatory social wasps of the genera Vespula and Dolichovespula. Members of these genera are known simply as "Wasps" in other English-speaking countries. Most of these are black and yellow like the eastern yellowjacket and the aerial yellowjacket ; some are black and white like the bald-faced hornet. Some have an abdomen with a red background color instead of black. They can be identified by their distinctive markings, their occurrence only in colonies, and a characteristic, rapid, side-to-side flight pattern prior to landing. All females are capable of stinging. Yellowjackets are important predators of pest insects.
Yellowjacket
Face of a southern yellowjacket (Vespula squamosa)
Yellowjacket stinger in its sheath in a scanning electron microscope
Vespula squamosa queen
A wasp is any insect of the narrow-waisted suborder Apocrita of the order Hymenoptera which is neither a bee nor an ant; this excludes the broad-waisted sawflies (Symphyta), which look somewhat like wasps, but are in a separate suborder. The wasps do not constitute a clade, a complete natural group with a single ancestor, as bees and ants are deeply nested within the wasps, having evolved from wasp ancestors. Wasps that are members of the clade Aculeata can sting their prey.
Wasp
Polistes sp., India
Megascolia procer, a giant solitary species from Java in the Scoliidae. This specimen's length is 77 mm (3.0 in) and its wingspan is 115 mm (4.5 in).
Megarhyssa macrurus, a parasitoid. The body of a female is 50 mm (2.0 in) long, with a c. 100 mm (3.9 in) ovipositor