Parasitic Wasps

Parasitic Wasps belong to the order Hymenoptera, which contains more parasites than any other insect order. Many insects in the order Hymenoptera, such as wasps, sawflies, ants and bees, are not parasitic.

Adults of many species are very small (ranging from 1/100 to 3/4 inch long) and often go unnoticed. They vary in shape and coloration but usually have long, thread-like (filiform) antennae or they may appear elbowed, clear or colored wings with characteristic venation and a narrow “waist” between the thorax and abdomen. Females of many species have a spine-like egg-laying structure (ovipositor) at the tip of the abdomen.

Larval stages are usually not observed unless they are dissected from hosts or detected on the host (external parasites). They are usually cream colored, legless and tapered at both ends. Occasionally, caterpillars are observed with white silken cocoons of parasites (Braconidae) attached to their bodies. Stages of immature whiteflies parasitized with Encarsia formosa are darker or black when late in the parasite development compared to yellowish to creamy healthy ones.

Aphids are hosts for species in the subfamily Aphidiinae (Braconidae) such as Aphidius spp. and others in the family Aphelinidae . Parasitized aphids, called “aphid mummies”, appear puffed up, brown and hardened. The adult parasitic wasps chew a round hole in the abdomen to emerge.

Mouthparts of larvae and adults are for chewing. Larval stages of parasitic wasps develop inside or outside of a single host during one or more of the host’s developmental stages (egg, larvae, pupae or adult). Those that kill their hosts are called parasitoids. Most insect groups (including aphids, beetles, caterpillars, flies, sawflies, scale insects and true bugs) are attacked by parasitic wasps. Many species are host specific, developing in one or a limited number of related host species.

Life Cycle: The adult female wasp lays an egg in or on the body of a host insect. Common host insects in cropping systems are the aphids and larvae of Lepidoptera and Coleoptera. The egg hatches, and the larva feed in or on the host, eventually killing it. In some species, a single egg will produce multiple offspring.

If the larvae feed internally in a host, the wasp larvae may pupate in the body of the host or emerge from the body and pupate outside the host. If the larvae feed externally on a host, the wasp larvae will pupate outside the body of the host. Adults will mate, and multiple generations will occur per year. Overwintering stages are variable and in some species are unknown.

Management: Parasitic wasps are important naturally occurring biological control agents. Some species have been intentionally introduced to suppress pest insect populations. In Wyoming, these include parasitic wasps introduced to control alfalfa weevil and Russian wheat aphid. Some species are available for sale for greenhouse and backyard use.

The parasitic wasp is a natural method of aphid control. Green, black and white fly all cause tremendous damage to plants in our gardens and greenhouses. Parasitic wasps are harmless to humans and animals, and unlike aphids, do not damage greenhouse plants and fruit.

If you ever have any bug related questions feel free to call us either at Beyond Pest Control. Once again, and I can’t stress this enough we are on call twenty four hours a day seven days a week to kill those bugs, we aren’t kidding whether you call us at 9 am or midnight we will be available to take your call and either get rid of the bug infestation, or answer any questions you may have concerning the bug issue. I can honestly guarantee that there will be someone to answer that call. We make it our business to make you bug free!

If you have any questions about pest control check out the rest of our website or go to our blog at http://nypestpro.blogspot.com.

Beyond Pest Control.

Our pest control specialists service all NYC boroughs, including Queens, Brooklyn, Bronx, Manhattan, Long Island (both Nassau & Suffolk counties), Staten Island and even both Westchester & Rockland counties.