Description of Flower-Visiting
Wasp Families and Sub-Families
Bethylidae (Bethylid Wasps)
These wasps lay eggs on larvae, or sometimes pupae, of Dermestid beetles. The wasp larvae are ectoparasitoid. Bethylid wasps have stingers, may obtain nectar from flowers, but are not common visitors.
These tiny to small wasps have black legs, antennae, and wings, otherwise they are variously colored; they are more stout than Ichneumonid wasps. Braconids are parasitoid on various small insects. They obtain nectar from wildflowers, particularly members of the Carrot family, but are easily overlooked. They do not construct special brood nests, but fly off after implanting an egg on a host insect.
Chrysididae (Cuckoo Wasps)
These wasps are are metallic green or blue, with an integument that is thick, hard, and sometimes coarsely pitted. Cuckoo wasps have ovipositors, but usually lack stingers. They are usually brood parasites on other wasps and bees, but some species are parasitoid on walking sticks, sawfly larvae, and other insects. Cuckoo wasps are occasional visitors to flowers; they are not particularly common.
Formicidae & Myrmicidae (Ants)
Ants are small to medium-sized insects that usually live in the ground, within cavities of trees, or rotting wood of buildings. They are various shades of black, brown, or red. Ants are highly social insects, consisting primarily of sterile workers without wings. Ants tend to be omnivorous scavengers, although some species cut leaves for their underground fungus farms, while others tend aphids for their honeydew. Ants sometimes visit flowering plants for nectar, particularly those with extra-floral nectaries, such as Trumpet Creeper, Wild Senna, and Partridge Pea. Species observed on such wildflowers include Acrobatic ants, Mound ants, and Carpenter ants.
Gasteruptiidae (Wild Carrot Wasps)
These are large slender wasps, resembling Ichneumonid wasps in appearance. They are dark, long, and slender, with small patches of yellow or red on the abdomen. Wild Carrot wasps invade the nests of other wasps and bees, where their larvae are parasitoid on these host insects. As the common name suggests, they obtain nectar from members of the Carrot family, but are not often observed.
Ichneumonidae (Ichneumonid Wasps)
These are dark slender wasps with very narrow waists, usually fairly large, with long ovipositors. Most species don't have stingers. They are parasitoid on beetle larvae, sawfly larvae, and other kinds of insects; each species is host specific. They don't construct special brood nests, instead flying off after laying their eggs on the host insect. There are many known species, and even more waiting to be identified. They visit flowers for nectar, favoring members of the Carrot family.
Mutillidae (Velvet Ants)
Velvet Ants are hairy, brightly colored wasps, covered with orange, yellow, red, or black hairs. Their integument is exceptionally hard, and the wingless females can deliver a powerful sting. Velvet Ants invade the nests of other wasps and bees to lay their eggs (brood parasitism). Their carnivorous larvae devour the grubs of these other insects. They are uncommon visitors to flowers, but sometimes Velvet Ants seek nectar from members of the Carrot family and plants with extra-floral nectaries (e.g., Partridge Pea).
Pompilidae (Spider Wasps)
Spider Wasps are usually black, sometimes with patches of yellow or red. They have stingers, which they use to paralyze spiders. The spider is then dragged back to its den or to a specially constructed chamber in the ground, whereupon a single egg is laid on the spider, and the chamber is sealed. The wasp larvae are parasitoid on spiders. Spider wasps are fairly common visitors to flowers.
Sapygidae (Sapygid Wasps)
These wasps invade bee nests, where the larvae feed on the pollen and nectar supplies of the host insect. Sapygid wasps are usually black, with white or yellow markings. The adults obtain nectar from flowers, but they don't gather any pollen or nectar for their larvae, unlike bees. They are not common.
Scoliidae (Scoliid Wasps)
Scoliid Wasps are large, hairy, and colorful. These wasps have stingers, which they use to paralyze the larvae of Scarab beetles. While there are only a few species in this family that occur in Illinois, they are avid seekers of flower nectar.
Sphecidae (Sphecid Wasps)
This is a large and varied assortment of solitary wasps consisting of several families. When at rest, the wings of these wasps do not appear pleated (unlike Vespid wasps). They all possess stingers, which are used for self-defense and to paralyze prey. Sphecid wasps visit many kinds of wildflowers. Astatinae (Astatinine Wasps): These wasps prey on stinkbugs; they are not common flower visitors. Bembicinae (Sand Wasps): These stout wasps dig burrows in loose soil, and often nest gregariously. They are yellowish or tan wasps with brown or black markings, particularly on the abdomen. They prey on flies, small bees, plant bugs, or caterpillars. One species, Sphecius speciosus, preys on cicadas and is known as the "Cicada Killer." Crabroninae (Crabronine Wasps): These wasps usually prey on flies, although some prey on plant bugs. Important groups include Anacrabro spp., Crabro spp., Ectemnius spp., and Oxybelus spp. Larrinae (Larrine Wasps): Important groups in this family are Tachytes & Tachysphex spp. (Sand-Loving wasps), which prey on grasshoppers, and Ancistromma spp., which prey on crickets. Many of these species favor open sandy areas, and dig extensive burrows for the brood cells. Philanthinae (Philanthine Wasps, Bee Wolves Beetle Wasps): The Philanthus spp. are black with yellow markings, and are called "Bee Wolves." They attack worker bees (often Halictid bees), which they paralyze and carry back to the nest. Another important group consists of the Cerceris & Eucerceris spp., which attack the larvae of various weevils and beetles. They are large-sized, brown, with cream markings or stripes, and dig nests in the ground around their prey. Sphecinae (Sphecine Wasps): These wasps are small to large-sized, black, brown, or blue, with white or yellow markings. They usually construct nests underground, but some species make tunnel-like mud nests, which are affixed to rocks, buildings, and other protected places. Important groups are the slender Ammophila spp. (Thread-Waisted Wasps), which prey on moth and sawfly larvae; Chlorion spp. (Cricket-Hunter Wasps), which prey on crickets; Sceliphron spp. (Mud Daubers), which prey on spiders; and Prionyx & Sphex spp. (Digger Wasps), which prey on grasshoppers. An example of the latter is Sphex ichneumonea (Great Golden Digger Wasp).
Tiphiidae (Tiphiid Wasps)
These wasps are often black, with yellow or red markings. They have stingers, which are used to attack ground-dwelling larvae of Scarab beetles or Tiger beetles. Tiphiid wasps obtain nectar from flowers. While there are few species that occur in Illinois, some of them, such as Myzinum quinquecincta (Five-Banded Tiphiid Wasp), are common visitors to prairie wildflowers.
Vespidae (Vespid Wasps)
These medium to large wasps may be light brown, reddish brown, or black with yellow markings, especially around the face and on the abdomen. At rest, their wings appear pleated. These wasps exhibit varying degrees of sociality. The Polistes spp. (Paper Wasps) construct only small clusters of brood cells from paper (chewed plant material), while Vespula & Dolichovespula spp. (Yellow Jackets and Hornets) construct large spheroid nests from the same kind of material. These wasps bring back a variety of insects back to the nest (with hornets providing regurgitated food to their larvae). They have a reputation of being aggressive around their hives. There is a subfamily of the Vespidae that consists of solitary wasps, which will be discussed next. Eumeninae (Eumenine Wasps): Eumenine wasps are rather stout, medium-sized, brown with cream or yellow markings. They make mud-lined nests in the ground, or make pot-shaped nests from mud on the twigs of shrubs and small trees, or construct nests in wood cavities. Eumenine wasps attack caterpillars of moths, and carry them back to their nests as a food source for their larvae. Some species also prey on beetle grubs in the ground. Eumenine wasps are also frequent visitors of wildflowers.