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Parasitoids & Parasites

9-10-15 pelecinid wasp with mites 071By definition, a parasitoid is an organism that lives on or in a host organism and ultimately kills the host. The pictured Pelecinid Wasp is a parasitoid. Its host is the grub, or larval stage, of June Bug beetles. The female Pelecinid Wasp uses its long abdomen to probe into the soil until it locates a June Bug grub and then it lays an egg on the grub. When the egg hatches, the wasp larva burrows into and feeds on the grub, eventually causing its death.

A parasite is much like a parasitoid, deriving nutrients from a host, but, unlike a parasitoid, a parasite does not usually kill its host. Often parasites are much smaller than their host, and frequently live in or on their host for an extended period of time. In this photograph, a parasitoid, the Pelecinid Wasp, is host to reddish parasitic mites (located on its thorax).

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7 responses

  1. Susan Holland

    Another fascinating fact to start my day with!!! Thank you!

    September 9, 2015 at 8:09 am

    • Thank you, dearest sister in the whole, wide world!

      September 9, 2015 at 8:51 am

  2. Wonderful post: parasitoid and parasite all in one image. Female Pelecinid wasps are amazing looking creatures! I’ve photographed quite a few dragonflies with mites, but have never seen mites on any other insects. How common are they?

    September 9, 2015 at 10:04 am

    • I think quite. Many grasshoppers have them (bright red), and I’ve also seen them on dragonflies, damselflies and a number of other insects, but mostly on grasshoppers!

      September 9, 2015 at 12:41 pm

  3. Jean Haarrison

    I agree on wonderful image of parasitoid and parasites.

    September 9, 2015 at 1:31 pm

  4. Wow, so fascinating, Mary. The hunter becomes the hunted! Great macro shot!

    September 9, 2015 at 4:32 pm

  5. What a great shot of ovipositor as weapon!

    September 9, 2015 at 8:57 pm

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