Exploring the Scarab Hunter Wasp: Quick Facts for Enthusiasts

The fascinating world of insects includes a diverse array of species, and among them is the Scarab Hunter Wasp. Known for their unique appearance and intriguing behavior, these solitary wasps have become a topic of curiosity for many.

Scarab Hunter Wasps primarily belong to the thread-waisted wasps (Sphecidae) and digger wasps (Crabronidae) families. They vary in size, ranging from less than 1/2 inch long to 1-1/2 inches long, with slender to stout bodies. These wasps exhibit various colors like black and yellow, or black and other shades, making them visually captivating creatures.

Apart from their striking looks, these wasps play a significant role in controlling scarab beetles, which can cause extensive damage to plants. So, by learning more about Scarab Hunter Wasps, you’ll not only satisfy your curiosity but also gain an appreciation for their ecological importance.

Identification and Characteristics

Physical Features

Scarab Hunter Wasps are fascinating insects belonging to the order Hymenoptera. They are large arthropods known for their striking appearance. Some notable features of these wasps include:

  • A prominent abdomen
  • Two pairs of wings
  • Short antennae

In particular, the Yellow Scarab Hunter Wasp is known for its vibrant coloration. This species displays a beautiful, bright yellow color with black markings on its body.

Types and Species

There are several species of Scarab Hunter Wasps, which belong to different subfamilies within the Scoliidae family. Some examples include:

  • Scoliid Wasps: These are generally large and hairy, often seen hovering around flowers or lawns.
  • Campsomerinae: A subfamily consisting of several species, such as the Dielis genera.
  • Dielis pilipes: Also known as the Yellow-legged Scarab Hunter Wasp, it is well-known for hunting scarab beetle larvae.

Here’s a quick comparison of two species within the Scoliidae family:

Species Subfamily Major Features
Dielis pilipes Campsomerinae Yellow legs, hunts scarab beetle larvae
P. crinita Scoliid Wasps Large, hairy, strong flying, often near flowers

By understanding the physical features and types of Scarab Hunter Wasps, you can easily identify these unique insects and appreciate their role within the ecosystem.

Life Cycle and Reproduction

From Egg to Adult

The life cycle of a Scarab Hunter Wasp is fascinating. These solitary wasps go through several stages, including the egg, larval, pupal, and adult stages. When a female wasp finds a suitable host, such as a scarab beetle larva, she lays her egg on or near it. This is necessary because the wasp larva will eventually feed on the beetle larva.

While the wasp egg is developing, the host remains alive, ensuring a fresh food source for the emerging wasp larva. Upon hatching, the wasp larva begins consuming the beetle larva, eventually killing it. Once the host is consumed, the wasp larva spins a cocoon and enters the pupal stage.

During the pupal stage, the wasp larva undergoes a metamorphosis, transforming into an adult Scarab Hunter Wasp. This process takes a variable amount of time, depending on the species and environmental conditions.

Reproductive Habits

Scarab Hunter Wasps exhibit some unique reproductive behaviors. Remember, they are solitary creatures, so finding a mate can be a challenge. Male and female wasps will typically seek each other out using visual and chemical cues. After mating, the female goes on a search for scarab beetle grubs to lay her eggs on.

In summary, the life cycle of a Scarab Hunter Wasp is characterized by several distinct stages, from the egg to the adult. They are solitary creatures with fascinating reproductive habits, which involve the female laying her eggs on the larvae of scarab beetles as a food source for her offspring while they develop.

Habitat and Range

General Habitats

Scarab Hunter Wasps are known to inhabit areas with a variety of soil types. You can often find them in places with sandy banks, which serve as ideal nesting sites. These wasps are attracted to environments offering ample sunlight and minimal vegetation, as it allows them to efficiently locate their prey – Scarab beetle larvae. In these habitats, you’ll notice their nests are created in loose soil and can be easily recognized by their cylindrical shape and small entrance hole.

Geographical Distribution

Scarab Hunter Wasps have a widespread range, spanning across multiple continents. They are predominantly found in:

  • USA: Particularly in California and Southern Okanagan Valley
  • Canada: In British Columbia, specifically the Similkameen valleys and Summerland region
  • Europe: Widespread presence in various countries
  • Asia: Found in multiple regions

It’s crucial to note that their distribution may vary depending on the specific species of Scarab Hunter Wasp, weather patterns, and availability of prey.

Diet and Feeding Habits

Primary Diet

Scarab Hunter Wasps primarily feed on the grubs of beetles, especially those from the Scarab family. These wasps also consume nectar from flowers as an energy source. Some examples of flowers they may visit include elderberry and other flowering plants.

Feeding Habits

As a Scarab Hunter Wasp, your main hunting strategy is to search for grubs by digging in the soil. Once you find a grub, you paralyze it with your sting and then lay an egg on it. The hatched larva will eventually feed on the immobilized prey.

While hunting for grubs, you also play an essential role in pollinating the flowers you visit for nectar. By visiting different flowers, you inadvertently transfer pollen between them, helping the reproduction of plants. Here’s a summary of the feeding habits:

  • Grubs as the main food source
  • Nectar from flowers for energy
  • Pollinating flowers during nectar feeding

Remember, as a Scarab Hunter Wasp, you have a unique and crucial role in maintaining the balance of your ecosystem and the reproduction of flowering plants.

Interactions with Other Species

Predator-Prey Relationships

Scarab Hunter Wasps are known to have a close relationship with various beetle species, especially the ones belonging to the Scarab family. These wasps are considered beneficial because they help manage populations of scarab beetles, which can be harmful to plants and crops. For instance, Scarab Hunter Wasps prey upon Japanese beetles, June beetles, lined June beetles, and ten-lined June beetles.

Their larvae primarily feed on the larvae of beetles. When the adult female wasps locate scarab beetle grubs, they paralyze the prey with their stingers and lay their eggs near or on the paralyzed beetle larvae. Once the wasp larva hatches, it consumes the beetle larva, effectively controlling the beetle population.

Interaction with Humans

Scarab Hunter Wasps are not considered aggressive towards humans; however, they might sting if they feel threatened. Their stings can be painful but are usually not life-threatening. It is essential to maintain a respectful distance from these wasps to avoid upsetting them.

Regarding interaction with other flying insects like bees, ants, and yellow jackets, Scarab Hunter Wasps are relatively non-territorial, meaning they will not often engage in conflict with these insects. Their primary focus is locating and hunting scarab beetle larvae.

To better understand the differences between Scarab Hunter Wasps and Yellowjackets, see the comparison table below:

Feature Scarab Hunter Wasp Yellowjacket
Primary Prey Scarab beetle larvae Various insects
Aggressiveness Not aggressive Can be very aggressive
Sting Painful, but not severe Painful, can be dangerous
Habitat Grasslands, gardens Underground nests
Interactions with Bees Non-territorial Can be territorial

In conclusion, Scarab Hunter Wasps can be a fascinating species to learn about, but it is good to remember that they play a vital role in controlling beetle populations and reducing negative impacts on plant and crop growth. Treat them with caution and a healthy level of respect to avoid any painful encounters.

Significance in Ecosystems and Agriculture

Role in Ecosystems

The Scarab Hunter Wasp plays a crucial role in maintaining the balance of ecosystems. They are natural predators of various beetle larvae, particularly those belonging to the scarab beetle family. By feeding on these larvae, they help to keep their populations in check, preventing them from causing significant damage to plant life.

Additionally, some species of Scarab Hunter Wasps are known to be pollinators, contributing to the reproduction of different plants. By visiting flowers in search of nectar, they inadvertently transfer pollen from one bloom to another, assisting in the pollination process.

Impact on Agriculture

As biological control agents, Scarab Hunter Wasps can be valuable allies for farmers. By preying on the larvae of agricultural pests like the Japanese beetle and May beetle, they aid in reducing the need for chemical pesticides. This natural biological control helps protect crops from damage and ensures a more sustainable approach to agricultural practices.

For example, Canadian records indicate that some Scarab Hunter Wasp species have been effective in controlling populations of destructive beetles in blueberry fields. This showcases the potential benefits of promoting these wasps as part of an integrated pest management strategy.

However, it is essential to consider that the overall impact of Scarab Hunter Wasps on agriculture may vary depending on factors such as species, location, and farming practices. Consequently, it is crucial to consult with experts and conduct further research before implementing them as part of a pest management plan.

Protection and Conservation Efforts

Scarab Hunter Wasps play a crucial role in controlling the population of pests, such as scarab beetles, in various ecosystems. To ensure their survival and maintain ecological balance, certain protection and conservation efforts need to be implemented. One way to do this is by preserving their natural habitats.

You can contribute to their conservation in your own backyard by creating a favorable environment for these wasps. Provide them with adequate nesting sites and plant native flowering plants to offer food sources for adult wasps. Additionally, avoid using chemical pesticides that may harm these beneficial insects.

At a larger scale, efforts such as the establishment of Habitat Conservation Plans can protect and enhance the habitats of various species, including the Scarab Hunter Wasp. Landowners may also receive support and incentives from the U.S. Fish and Wildlife Service to conserve and manage their lands and resources in a way that benefits at-risk species, like the Scarab Hunter Wasp.

Remember, even small efforts count when it comes to the protection and conservation of these fascinating insects. By taking part in those initiatives, you’re helping to maintain the balance of ecosystems in your area and ensuring the survival of these essential predators.

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.

Letter 1 – Scarab Hunter Wasps from Morocco

 

Subject:  Rabat Morocco, lovely wasps everywhere
Geographic location of the bug:  Rabat, Morocco
Date: 07/10/2018
Time: 03:31 PM EDT
Your letter to the bugman:  As July began, I saw more holes in the soil, and then these large and lovely creatures emerging from them. Now they are everywhere, buzzing about the bougonvillia, feasting on the marjoram, and dancing over the roses. They are about 1″ long, and though the pictures don’t show it well, they have yellow markings that are similar to the scolid wasp pictures supplied by others on the Mediterranean. It also has interesting segmented orange antennae.
How you want your letter signed:  Moroccan wasp fan

Scarab Hunter Wasp

Dear Moroccan wasp fan,
Your images of this gorgeous Scarab Hunter Wasp or Flower Wasp in the family Scoliidae are truly beautiful as well.  We are having trouble identifying your exact species, but your individual’s similarity to this FlickR image of
Scolia bidens from Mallorca causes us to speculate that you have captured images of a different Scolia species that also has distinctive orange antennae.

Flower Wasp

Thank you! They are really quite neat, especially because I had been wondering why there were so many holes. In Morocco, we have no screens so we share our home with any number of insects (there is a constant game with the ants, I hide the honey and they find it), but these ones are my favorite so far. I do feel a bit sad for the big bumbling beetles though, I assume the number of wasps is sadly inverse to the number of those ‘junebugs’ we saw.
Andrea

Hi again Andrea,
Insect populations do ebb and flow, so when prey is plentiful, the population of predators increases, and when prey is scarce, you will see fewer predators.  This is what keeps nature in balance.

Letter 2 – Scarab Hunter Wasp from Greece

 

Subject:  Wasp like insect
Geographic location of the bug:  Skopelos, Greece
Date: 09/12/2018
Time: 07:22 AM EDT
Your letter to the bugman:  On holiday this insect settled on me and was quite happy so folded its wings . Have asked some locals but they don’t know what it is .
How you want your letter signed:  Vivien

Scarab Hunter Wasp

Dear Vivien,
This is a magnificent Scarab Hunter Wasp and thanks to images on pBase and on FlickR, we are confident it is
Scolia hirta.

Scarab Hunter Wasp

Letter 3 – Scarab Hunter Wasp from Kenya

 

Subject:  Not sure if it’s a wasp
Geographic location of the bug:  Mombasa, Kenya
Date: 12/30/2019
Time: 10:33 PM EDT
Your letter to the bugman:  I’ve been wanting to post here for a while. I’m Kenyan and our bugs are not available on the internet as much as in Western or Asian countries. Since I live in a coastal area, I see so many insects that I would love to have identified. My home area has a lot pf insects that usually find their way into the house. I found my sister, Sian, had killed this one and upon closer inspection wanted to know if it’s a spider wasp, a great black wasp or even a wasp at all (though it has the tell tale slim “waist”). The species I found online of the spider wasp all have antennae that are brightly colored but this one only had orange tips. I thought it was a great black wasp, because of the sudden increase in grasshopper populations, but most sites say they are large and have no colored antennae. The body is hairy (including the abdomen) and shiny and it has “gradient” wings which change between a dark blue to black depending on the angle. Hoping to post more bugs in future…
How you want your letter signed:  Danson, future regular poster…

Scarab Hunter Wasp

Dear Danson,
This is definitely a wasp, but it is not a Spider Wasp.  In our opinion, it is a Flower Wasp or Scarab Hunter in the family Scoliidae, a group that preys upon the underground grubs of large Scarab Beetles, and Africa has numerous species of large Scarab Beetles, so there is a food supply for the Scarab Hunter Wasps.  We have not had any luck providing you with a species match.  According to BugGuide, a North American site, Scarab Hunter Wasps are “Robust, hairy, medium-sized to large.”  We look forward to your future submissions.

Thank you very much for the fast response… I’ll definitely post more…and you’re right, I think it’s a species of flower wasp…

Letter 4 – Female Scarab Hunter Wasp: Campsomeris tolteca

 

Subject: Bee on Steroids?
Location: Los Angeles, CA
June 27, 2014 3:10 pm
I saw this bee-hemouth on a flower outside my home here in the Los Angeles area.
It was around 1.5 inches long.
Looks like a bee, but isn’t a bee. Any ideas?
Signature: Just Me

Female Scarab Hunter Wasp
Female Scarab Hunter Wasp

Dear Just Me,
Several years ago we encountered this magnificent species of Scarab Hunter Wasp in Elyria Canyon Park in Northeast Los Angeles and we identified it as a female
Campsomeris tolteca.  The species exhibits pronounced sexual dimorphism.  Both males and females visit flowers, but only the female hunts for Scarab Beetle Grubs to feed her brood.  BugGuide states:  “According to Nick Fensler: The females Campsomeris as well as other members of the subfamily Campsomerinae are predators on white grubs (Scarabaeidae), using these larvae as food for their young. Unlike sphecids, eumenines, and pompilids these wasps do not appear to have any type of prey transportation and dig to the ground-dwelling beetle larvae, sting it to paralyze it, and then lay an egg. They may dig around the grub to form a small cell. Since they use this nesting strategy they are often seen flying low to the ground (searching) in a figure eight pattern (but the flight pattern gets more erratic when they “smell” something). The adults use nectar as a food source and are common on flowers.”.  You may also compare your images to these images on BugGuide.

Female Scarab Hunter Wasp
Female Scarab Hunter Wasp

Wow very cool! I think it looks more like the plumipes. Thanks so much!

According to BugGuide, Campsomeris plumipes is not found west of Colorado.

Letter 5 – Female Scarab Hunter Wasp in Mount Washington

 

Scarab Hunter Wasp
Scarab Hunter Wasp

Subject:  Female Scarab Hunter Wasp
Location:  Mount Washington, Los Angeles, California
August 18, 2016 9:30 AM
Just as we were leaving the office today to gawk at the guerilla art Donald Trump sculpture at Wacko (see LA Times or LAist ), we had to make a slight delay to take some images of this gorgeous female Scarab Hunter Wasp,
Campsomeris tolteca, nectaring on the flowering peppermint.  We first identified this species four years ago in Elyria Canyon Park.  Alas, the statue was in for the night, so we will have to return to Wacko during business hours.   Our identification of the female Scarab Hunter Wasp can be verified on BugGuide.

Scarab Hunter Wasp
Scarab Hunter Wasp
Scarab Hunter Wasp
Scarab Hunter Wasp

Letter 6 – Mating Scarab Hunter Wasps

 

Subject:  Hot wasp lovin’
Geographic location of the bug:  Rio Grande Nature Center, Albuquerque NM
Date: 05/18/2018
Time: 04:23 PM EDT
Your letter to the bugman:  Hello!  We were in the nature center and came upon dozens of these wasps.   The smaller ones, which we assumed are males, were flying maybe an inch or so above the ground and clearly searching for something.  The larger one, which we assumed was a female, suddenly emerged from underground and the smaller ones went crazy.
She kept trying to get away but couldn’t fly because her wings weren’t dry.  I believe I caught the actual act of mating in one of the photos.  Are these scarab hunters?   It’s the closest we could come in identifying them, but there wasn’t an exact match in the field guide.
How you want your letter signed:  Mike

A pair of Scarab Hunter Wasps

Dear Mike,
Your images are awesome, and your written commentary is a marvelous observation.  We agree that these are Scarab Hunter Wasps in the family Scoliidae, but we are not certain of the species.  Our best guess is perhaps
Crioscolia alcione (see female here on BugGuide and male here on BugGuide) or possibly Trielis octomaculata which is also pictured on BugGuide.  Members of this family exhibit sexual dimorphism, and males are smaller and often with markings different from those of the females.  Based on your observations, the males sensed the pheromones of the female that was about to emerge, and they waited for her to dig to the surface. 

Mating Activity among Scarab Hunter Wasps

Thank you!  That certainly looks like them.  There were dozens and dozens of the males searching everywhere.  They were quite friendly and just zipped around us with mild interest.

Male Wasps are physically incapable of stinging. 

Mating Scarab Hunter Wasps
Oh yeah, right?  The stinger is a modified ovipositor.
The sheer number of searching males was the most impressive thing.  There were easily 4-5 per square foot.

Letter 7 – Scarab Hunter

 

Subject: What type of bee is this?
Location: Payson, AZ
September 23, 2013 9:56 pm
I found a beautiful orange and black bee on our property, in Arizona, that has black and blue iridescent wings. I took a photo of it that I am attaching.
Would Love to find out what this beautiful creature is! :O)
Thanks for your help!
Signature: Vicki

Scarab Hunter
Scarab Hunter

Hi Vicki,
This Scoliid Wasp is positively gorgeous.  According to BugGuide:  Wasps in the family Scoliidae are commonly called:  “Flower Wasps, Mammoth Wasps, Scarab Hawks,  [or] Scarab Hunters” and the “female digs down to the host grub, stings it, and lays an egg on the paralyzed grub” and those eggs develop into “Larvae [that] are parasitoids of ground-dwelling scarab grubs.”  Thanks to BugGuide, we have identified you Scarab Hunter as 
Triscolia ardens.

Letter 8 – Scarab Hunter is Double Banded Scoliid

 

Subject: Megascolia maculata, mammoth wasp in Ontario?
August 15, 2014 5:18 pm
Hello,
Is there a subspecies of Megascolia maculata, not cicada killer, known to live in Eastern Ontario? Will send photos later if need be.
Signature: Noah

There are European Hornets.

Hi there,
I am trying to identify the species in the photo I’ve attached. It looks closest to photos of European/Eurasian mammoth wasps that I’ve seen.
Noah Cole

Double Banded Scoliid
Double Banded Scoliid

Dear Noah,
This Scarab Hunter Wasp is a Double Banded Scoliid,
Scolia bicincta.  According to BugGuide:  “No doubt a parasitoid of beetle larvae, as are other members of this genus.”

Letter 9 – Scarab Hunter Wasp

 

What is this?
At first I thought I had some photos of the Cicada Killer wasp……… but now I’m not sure. In fact, I think I have something else…. coloration is not exactly right. However, here is a photo of my Bee/Wasp ?? nectaring on Milkweed. Question: What it? Haven’t seen this coloration before in our garden. We do seem to have lots of various types of bees and wasps lately. Location: Palm Beach Gardens, FL (southeast coast)
Pete

Hi Pete,
This looks to us like a Scarab Hunter Wasp, Campsomeris pilipes. The adults take nectar and the larvae feed on scarab beetle larvae. The female wasp provisions the underground nest with the beetle larvae.

Letter 10 – Scarab Hunter Wasp

 

Washed ashore ?
Wed, Mar 11, 2009 at 12:22 PM
I was walking down Vince beach, FL in the begining of March. I see many different inscets lying in the sand, but this particular one I have never seen before. Iwas woundering what kind of insect it is and what is the use of its large mandibles.
Chris Franklin
vince,fl

Scarab Hunter Wasp
Scarab Hunter Wasp

Hi Chris,
This is a Scarab Hunter Wasp in the genus Campsomeris. BugGuide has this remark: “According to Nick Fensler: The females Campsomeris as well as other members of the subfamily Campsomerinae are predators on white grubs (Scarabaeidae), using these larvae as food for their young. Unlike sphecids, eumenines, and pompilids these wasps do not appear to have any type of prey transportation and dig to the ground-dwelling beetle larvae, sting it to paralyze it, and then lay an egg. They may dig around the grub to form a small cell. Since they use this nesting strategy they are often seen flying low to the ground (searching) in a figure eight pattern (but the flight pattern gets more erratic when they “smell” something). The adults use nectar as a food source and are common on flowers.” We are confident your specimen is Campsomeris quadrimaculata, a robust wasp with a distinctly marked abdomen, which is well documented on BugGuide including many sightings from Florida.

Letter 11 – Scarab Hunter Wasp

 

Very large flying insect in compost pile
May 16, 2010
I first saw this bug when I was emptying yard trimmings onto the compost pile. Unfortunately I saw it too late that day and it got covered by the trimmings. It is very large 1 3/4 -2 inches with very bright orange bands on its abdomen? One thing I do remember was when I first saw it’s abdomen had bands of black hair/fur around the orange bands. With this siting It was crawling around on the ground about 10 feet from my compost pile. It now seems to be relatively smooth and if anything not as large as the previous time I saw it. Sorry for the photos all I had was my iphone… I have the good camera at the ready if I see it again.
Darin Davis
Austin, Central Texas, USA

Scarab Hunter Wasp

Moth or Fly?
May 16, 2010
I recently posted a request for ID with some rather poor photos. Got another chance at photography with better results. Previous post… first saw this bug when I was emptying yard trimmings onto the compost pile. Unfortunately I saw it too late that day and it got covered by the trimmings. It is very large 1 3/4 -2 inches with very bright orange bands on its abdomen? One thing I do remember was when I first saw it’s abdomen had bands of black hair/fur around the orange bands. With this siting It was crawling around on the ground about 10 feet from my compost pile. It now seems to be relatively smooth and if anything not as large as the previous time I saw it. Sorry for the photos all I had was my iphone… I have the good camera at the ready if I see it ag ain.
Darin Davis
Austin, Central Texas, USA

Scarab Hunter Wasp

Hi Darin,
We really want to thank you for going through the trouble to provide better images. Your first set would have made identification quite difficult if not impossible, though we knew by your written description that you probably had a Scarab Hunter Wasp in the genus Campsomeris, but we would not have ruled out a Digger Wasp in the genus Scolia. Your new photos will allow us to correctly identify it as the former, a Scarab Hunter Wasp in the genus Campsomeris, which takes nectar, according to BugGuide, and “Females provision nests with beetle larvae, esp. scarabs.
” If your compost pile is like ours, there are probably numerous Scarab Beetle Grubs in it so that is is a rich hunting ground for the female Scarab Hunter Wasp. BugGuide also indicates: “Eric Eaton has pointed out in comments under various photos of Scoliids that there is considerable taxonomic confusion in this family, so that has to be a caveat in any photo identified as to genus here. According to Nick Fensler: The females Campsomeris as well as other members of the subfamily Campsomerinae are predators on white grubs (Scarabaeidae), using these larvae as food for their young. Unlike sphecids, eumenines, and pompilids these wasps do not appear to have any type of prey transportation and dig to the ground-dwelling beetle larvae, sting it to paralyze it, and then lay an egg. They may dig around the grub to form a small cell. Since they use this nesting strategy they are often seen flying low to the ground (searching) in a figure eight pattern (but the flight pattern gets more erratic when they “smell” something). The adults use nectar as a food source and are common on flowers.” Unless there are future taxonomic changes, we would identify your wasp as Campsomeris ephippium based on BugGuide’s images, and all reports on BugGuide’s data page were from Texas.

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