The Crypt-Keeper Wasp: A Hyperparasite and Effects on Its Host

Updated on September 28, 2019
AliciaC profile image

Linda Crampton is a writer and teacher with an honors degree in biology. She loves to study nature and write about living things.

A crypt-keeper wasp
A crypt-keeper wasp | Source

An Interesting Hyperparasite

The crypt-keeper wasp (Euderus set) is an interesting and attractive insect that was discovered in 2017. It’s a hyperparasite, or one whose host is also a parasite. It parasitizes an insect known as the crypt gall wasp (Bassettia pallida). The crypt-keeper wasp controls the crypt gall wasp’s behaviour, forcing it to do the parasite’s bidding and killing it after it has served its function.

For many people, the word "wasp" probably conjures up the image of a large, black and yellow insect that is capable of giving a painful sting. Though these insects can be very annoying, they are only a small component of the wasp group. Most wasps are parasites that don't sting. Parasitic wasps are one of the largest groups of insects. Some species can be very helpful in controlling pests.

Classification of the Insects

Phylum Arthropoda

Class Insecta

Order Hymenoptera

Family Eulophidae (includes the crypt-keeper wasp)

Family Cynipidae (includes the crypt gall wasp)

Origin of the Crypt-Keeper Wasp's Name

The species name in Euderus set comes from Set, the name of the Ancient Egyptian god of evil and chaos. Set was also known as Seth. One of the stories about the god describes him trapping his brother Osiris in a crypt and then killing him. A crypt is an underground chamber that is often located under a church and used for a burial.

The crypt-keeper wasp enters the gall or "crypt" of the crypt gall wasp, where the latter insect dies from the effect of E. set's actions. The species name is apt because the sequence of events is reminiscent of the god's behaviour.

Euderus set was discovered and named by scientists at Rice University in the United States. The insect was discovered in Florida but has now been found in other states in the southeastern U.S.

Facts About Euderus set

Insects are classified in the phylum Arthropoda and the class Insecta. Wasps, bees, ants, and sawfiles belong to the order Hymenoptera within the insect class. Euderus set belongs to the family Eulophidae within the Hymenoptera order.

The crypt-keeper wasp has an attractive body with an iridescent turquoise and green sheen. It's a tiny insect whose length ranges from little over a millimetre to slightly over two millimetres. The size might explain why it wasn't discovered until 2017.

It's intriguing to think about the hidden and often energetic activities of creatures too small for us to notice or appreciate without magnification. Being small doesn't necessarily mean that a creature is insignificant. The crypt-keeper wasp might be important.

A parasite is an organism that lives in or on another organism (the host) and obtains its food from this organism. It generally doesn't kill its host. Organisms in the parasitoid category of parasitism do kill their hosts at some point, however. Euderus set is a parasitoid because it infects and eventually kills the crypt gall wasp.

An oak apple is a gall on an oak tree.
An oak apple is a gall on an oak tree. | Source

Plant Galls

Galls are areas of abnormal tissue on or near the surface of plants. Their creation is a response to the presence of insects, mites, fungi, bacteria, and viruses. Their exact cause or causes are not completely understood. The abnormal tissue may result from irritation of the area or from stimulation by the parasite. The study of plant galls is called cecidology.

Galls generally appear as swollen structures on the surface of plant parts, as shown in the photo above. They have a wide variety of appearances and are often attractive as well as interesting. They are sometimes likened to benign (stationary and non-cancerous) tumours in humans. They are usually harmless, but when they're numerous they may create a problem. The gall sometimes benefits the invader in some way, such as by providing a protected area for an insect's eggs to develop.

Although the crypt gall wasp belongs to a family that often triggers the production of noticeable galls on plant surfaces, it produces atypical effects. An affected twig or branch may look a little swollen overall, but it has no external galls. Instead, the twig or branch contains small holes. Each leads to a compartment known as a crypt (or a gall) where the insect's egg develops. In a heavy infestation, a branch may have many holes and crypts. The crypt can be seen in the video above.

Scientists have recently discovered that the crypt-keeper wasp can also infect other species of gall wasps, including ones that create typical galls on oak trees. These galls are sometimes known as oak apples.

Quercus geminata or the sand live oak
Quercus geminata or the sand live oak | Source

Facts About Bassettia pallida

The crypt gall wasp is orange-brown in colour. Like its crypt, it can be seen in the video above. It lives in the southeastern United States and is a parasite of sand live oak trees, or Quercus geminata. It sometimes infects the southern live oak, or Quercus virginiana. The first tree is evergreen and is found on the coast of the southeastern United States. It grows in sandy substrates. The southern live oak is another evergreen tree that grows in the same region but is usually found in a different habitat. It grows in grasslands and forests.

The female wasp deposits her eggs in young stems. The eggs hatch and turn into larvae inside the crypts that form. Eventually pupae are produced followed by the production of the adult insects. The new adults chew a hole in the bark and escape. The immature crypt gall wasps obtain nutrients from the tree and are therefore categorized as parasites.

Oak Alley Plantation in Lousiana contains a walk bordered by Quercus virginiana, or southern live oaks
Oak Alley Plantation in Lousiana contains a walk bordered by Quercus virginiana, or southern live oaks | Source

The Relationship Between the Two Insects

A female crypt-keeper wasp (E. set) deposits her eggs in a compartment occupied by a crypt gall wasp (B. pallida). The relationship that develops between the insects is sometimes known as hypermanipulation because one parasite affects the behaviour of another.

A parasitized B. pallida chews an opening to the outside world in the wall of the crypt, as it would do if it was going to escape. The hole is too small, however. When the gall wasp tries to travel through it, its head becomes stuck in the hole and blocks the opening. A crypt-keeper wasp feeds on its body and eventually creates a tunnel in its head so that it can escape. The parasitoid somehow controls the ability of B. pallida to chew a hole of the correct size. E. set can escape from the hole but B. pallida can't.

The parasitoid appears to affect the adult stage of B. pallida. Both the larva and the pupa of the parasitoid are able to infect the adult crypt gall wasp. Researchers have discovered E. set individuals half inside and half outside their host's body. The parasitoid eats the gall wasp from the inside out, leaving bits of the exoskeleton (the outer covering) in the crypt.

The image below shows a male Biorhiza pallida, a relative of the crypt gall wasp. In real life, the wings are folded over the body. Like the crypt-keeper wasp, the insect can be seen with the unaided eye but is tiny.

A cynipid wasp known as Biorhiza pallida
A cynipid wasp known as Biorhiza pallida | Source

Control of the Host

The relationship describe above may sound more like predation than parasitism and the gall wasp may sound more like prey than a parasite host. E. set is categorized as a parasite and B. pallida as its host, however, because E. set appears to manipulate the host's behaviour and doesn't kill it immediately. This manipulation causes the host to behave in a way that benefits the parasite.

An interesting fact has been discovered experimentally. E. set is three times less likely to be able to create a successful emergence hole when it's left to its own devices than when B. pallida creates the hole. It seems to be beneficial to allow B. pallida to create the hole before killing it.

Some researchers suspect that the crypt-keeper wasp turns the crypt gall wasp into a "zombie", perhaps by means of a specific chemical or mixture of chemicals. Chemical control has been found in some other parasites. So far, however, none has been found in the crypt gall wasp. Reports about one insect "brainwashing" the other or about E. set being able to use "mind control" to influence B. pallida are premature and may not be accurate.

Another possibility to explain the control is that the parasitoid may begin attacking the host at just the right time. The timing and/or a specific behaviour may trigger the host to start the creation of a hole, but at some point it may become too weak to finish the job. The precise control of the exit hole size is impressive, whatever factor or factors are responsible .

Further research is needed in order to discover how the host is controlled and to learn more about the sequence of events in the crypt.

Studying the Crypt-Keeper Wasp

Since the crypt-keeper wasp has been discovered very recently, there is probably a lot more that can be learned about it. The new report about its ability to parasitize additional hosts besides the crypt gall wasp is an example of how little we know about the insect.

E. set is interesting biologically and may be important in other ways besides simply increasing our knowledge of parasitic wasps. Its effects on other insects may tell us something about their activity or even help to keep them under control. This may be very helpful if the other insects have benefits or disadvantages in our lives. The crypt-keeper wasp may be more significant than we realize.

References

  • Discovery of the crypt-keeper wasp from Rice University
  • Description of a new species of Euderus from ZooKeys and Pensoft
  • A parasitoid manipulates the behaviour of a parasite from The Royal Society Publishing and the US National Library of Medicine
  • The story of Set and Osiris (PFD document) from the University of Texas
  • Information about plant galls from Trees for Life (a registered Scottish charity)
  • The crypt gall wasp and its manipulation from New Scientist
  • The crypt-keeper wasp can control seven additional species from New Scientist

Questions & Answers

    © 2019 Linda Crampton

    Comments

      0 of 8192 characters used
      Post Comment
      • AliciaC profile imageAUTHOR

        Linda Crampton 

        3 weeks ago from British Columbia, Canada

        Thank you very much for such a kind comment, Mel. I find nature fascinating and appreciate its beauty, but I agree that it can also be cruel. I think some people like to avoid thinking about the unpleasant side of nature.

      • Mel Carriere profile image

        Mel Carriere 

        3 weeks ago from San Diego California

        You are always coming up with these articles on a topic that hardly anybody knows about, but is acutely interesting. I read this with the utmost fascination, and horror. Nature is a cruel, cruel place. Splendid work!

      • AliciaC profile imageAUTHOR

        Linda Crampton 

        4 weeks ago from British Columbia, Canada

        Hi, Patricia. I appreciate your comment. I admire wasps, too, but I'm careful when I observe them. Thank you very much for the visit and for the angels!

      • pstraubie48 profile image

        Patricia Scott 

        4 weeks ago from North Central Florida

        This is totally fascinating and at the same time horrifying. What a complex relationship is formed. It is simply quite a lot to imagine that these small creatures can execute their plan as they do. And how beautiful that crypt keeper is. I am no fan of any wasp as I am very allergic. I can admire them from a distance Thank you for filling in some holes in my gray matter. Angels are headed your way this afternoon. ps

      • AliciaC profile imageAUTHOR

        Linda Crampton 

        5 weeks ago from British Columbia, Canada

        Hi, Denise. The relationship is certainly interesting! Blessings to you, too.

      • PAINTDRIPS profile image

        Denise McGill 

        5 weeks ago from Fresno CA

        Fascinating and a bit scary: a zombie wasp. Wow. I didn't know about this. Thanks for the science info.

        Blessings,

        Denise

      • AliciaC profile imageAUTHOR

        Linda Crampton 

        2 months ago from British Columbia, Canada

        Thank you very much, Shaloo.

      • swalia profile image

        Shaloo Walia 

        2 months ago from India

        I have learnt more about Flora and fauna through your hubs than I did in my biology classes. Keep up the good work!

      • AliciaC profile imageAUTHOR

        Linda Crampton 

        2 months ago from British Columbia, Canada

        Hi, Dora. I appreciate your visit and comment. I think that nature is always interesting to investigate.

      • MsDora profile image

        Dora Weithers 

        2 months ago from The Caribbean

        Everything has a purpose, they say, so I accept that these wasps have some significance. Thanks for always bring us information we would not otherwise seek out, on these phenomenal creatures.

      • AliciaC profile imageAUTHOR

        Linda Crampton 

        2 months ago from British Columbia, Canada

        Thanks for the visit, Nithya. Nature can certainly be very surprising.

      • Vellur profile image

        Nithya Venkat 

        2 months ago from Dubai

        Nature has many surprises in store waiting to be discovered. Thank you for sharing an interesting and informative article about the crypt-keeper wasp.

      • AliciaC profile imageAUTHOR

        Linda Crampton 

        2 months ago from British Columbia, Canada

        Hi, Heidi. The fact that we are still discovering new species is amazing and exciting. Nature is impressive!

      • heidithorne profile image

        Heidi Thorne 

        2 months ago from Chicago Area

        Isn't it amazing that we're still discovering new species of plants and animals all the time! So fascinating. Thanks for introducing us to another new entry in our biological world!

      • AliciaC profile imageAUTHOR

        Linda Crampton 

        2 months ago from British Columbia, Canada

        Hi, Nell. Yes, it seems that many aspects of nature are still unknown. I think that parasitic wasps are interesting animals.

      • Nell Rose profile image

        Nell Rose 

        2 months ago from England

        They say nature is fascinating, and sometimes it will get a bit creepy. I think I read at the top that it was only discovered in 2017? Just goes to show what is out there that we know nothing about. How fascinating, and yes rather horrific!

      • AliciaC profile imageAUTHOR

        Linda Crampton 

        2 months ago from British Columbia, Canada

        Hi, Flourish. It is a strange situation, It will be interesting to see what else scientists discover about the relationship between the wasps.

      • FlourishAnyway profile image

        FlourishAnyway 

        2 months ago from USA

        This could be straight out of sci fi. How strange but true. I've seen those galls and wondered what they were.

      • AliciaC profile imageAUTHOR

        Linda Crampton 

        2 months ago from British Columbia, Canada

        Hi, John. I agree—the wasps are well named and their relationship is certainly interesting! Thank you for the comment.

      • Jodah profile image

        John Hansen 

        2 months ago from Queensland Australia

        Wow, Linda, I knew a lot of wasps were parasitic but had never read about this particular wasp. How well named it and it’s unfortunate host are. I found this very interesting, especially how it could exercise control over the host to create the perfect size for itself to escape.

      • AliciaC profile imageAUTHOR

        Linda Crampton 

        2 months ago from British Columbia, Canada

        Thank you for the visit and the comment, RoadMonkey.

      • RoadMonkey profile image

        RoadMonkey 

        2 months ago

        Very interesting, thanks. I had not known about hyperparasites before.

      • Kailua-KonaGirl profile image

        KonaGirl 

        2 months ago from New York

        Cool Beans! Thanks so much.

      • AliciaC profile imageAUTHOR

        Linda Crampton 

        2 months ago from British Columbia, Canada

        Hi, KonaGirl. Thanks for the visit. Some wasps can definitely sting! These include the familiar wasps that most people notice. Many more wasp species exist than these familiar ones, though. As I say, most wasps are parasites and can't sting. I'll add a few more words to the article about this topic.

        I appreciate your suggestion for my next article!

      • Kailua-KonaGirl profile image

        KonaGirl 

        2 months ago from New York

        A really interesting article. A couple of things caught my eye, other than the facts about the E set, in the second paragraph of the article.

        1) I am highly allergic to ALL insect stings (yupper. . . even skeeters) which makes me avoid yellow jackets and wasps like the plague. You stated that wasps don't sting humans. Is this really true? I no longer need to worry about wasp stings? Around here we have huge black ground wasps that are really scary looking and freak me out because of my allergies.

        2) I am now really interested in the wasps that may be beneficial to killing other insects in a vegetable garden because of another fact you listed, "Some species can be very helpful in controlling pests." I am going to research this, however, it would be an idea for your next article. Hint, hint.

      • AliciaC profile imageAUTHOR

        Linda Crampton 

        2 months ago from British Columbia, Canada

        That's an interesting description of a insect, Bill! Thanks for the visit.

      • billybuc profile image

        Bill Holland 

        2 months ago from Olympia, WA

        I get along fine with wasps. I leave them alone and they do the same for me...but in the "bee" world, they are the scariest looking. :) They always remind me of a flying battleship for whatever reason. :)

      working

      This website uses cookies

      As a user in the EEA, your approval is needed on a few things. To provide a better website experience, owlcation.com uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

      For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at: https://owlcation.com/privacy-policy#gdpr

      Show Details
      Necessary
      HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
      LoginThis is necessary to sign in to the HubPages Service.
      Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
      AkismetThis is used to detect comment spam. (Privacy Policy)
      HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
      HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
      Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
      CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
      Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the googleapis.com or gstatic.com domains, for performance and efficiency reasons. (Privacy Policy)
      Features
      Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
      Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
      Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
      Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
      Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
      VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
      PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
      Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
      MavenThis supports the Maven widget and search functionality. (Privacy Policy)
      Marketing
      Google AdSenseThis is an ad network. (Privacy Policy)
      Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
      Index ExchangeThis is an ad network. (Privacy Policy)
      SovrnThis is an ad network. (Privacy Policy)
      Facebook AdsThis is an ad network. (Privacy Policy)
      Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
      AppNexusThis is an ad network. (Privacy Policy)
      OpenxThis is an ad network. (Privacy Policy)
      Rubicon ProjectThis is an ad network. (Privacy Policy)
      TripleLiftThis is an ad network. (Privacy Policy)
      Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
      Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
      Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
      Statistics
      Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
      ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
      Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)
      ClickscoThis is a data management platform studying reader behavior (Privacy Policy)