The Bug Geek

Insects. Doing Science. Other awesome, geeky stuff.

A great (SHINY!) start to the bug season!

My wife and I were walking the dogs down our country road.  Out of the corner of my eye, I noticed a dark-coloured blob slowing making its way across the pavement to the gravel shoulder.  A blueish-black blob, actually. A SHINY blueish-black blob.  A sluggish wasp, perhaps?  No, better.  BEETLES!

“AAAAH!  I want them!!!”, I yelled, handing off the yellow dog and crouching down to get a closer look.

Oil beetles!  A pair…heavy-bodied, short-winged and gleaming; the larger female carried the male on her back. “Why don’t I have my camera?”, I bemoaned.

I scootched them into the baseball cap I was wearing and pinched the fabric closed into a sort of bag. 

“Should we head back home?”, my wife asked.  “Yes please”.  She wrangled all three dogs as I held my prize with both hands.

When I got in the house and peeked in my cap, they had uncoupled.  Rats.  So much for an arthroporn shoot.  I popped them in the fridge to chill out while I got my camera and scoped out a well-lit and not-too-windy nook in the yard. 

I removed my little subjects from where they sat next to the pickle jar and brought them outside.  The male soon sufficiently warmed to remember what he’d been up to before I’d so rudely interrupted them, and immediately got back to business.  The female did not appear too impressed, but relented to the piggy-backing. 


 I  carefully placed them on a large wind-fallen branch and watched them for a bit as they roamed.  Soon they stopped, and the male began to flirt, delicately touching the female’s head with his mouthparts and stroking her antennae with his own.  One of the most remarkable things about the male oil beetle is his highly modified antennae; they have a distinct “C” of enlarged and oddly-shaped segments near the mid-point. 

Modified male antennae

 Occasionally he would draw her antennae into the crook of the “C”, seeming to grasp them within.  On BugGuide, I saw someone refer to this action as “antennal foreplay”.  I only observed this particular behaviour a handful of times, and didn’t manage to get great pictures, but here’s one that shows it well enough so you can get the idea:

"Antennal foreplay"

Foreplay or no, his efforts apparently weren’t cutting it for the female.  She soon shrugged him off and trundled off on her own.  He took the hint and did the same. Since they’re flightless beetles, I used the opportunity to get a few portraits:



 At one point, I must have handled the female a little too roughly, as I noticed yellow beads of oil on her leg joints and on/around her head (see image below).  Oil beetles are named for this defense mechanism.  Droplets of hemolymph, containing cantharidin, are extruded; cantharidin can be a serious irritant, causing blisters in some (oil beetles are also called “blister beetles”).  I’ve handled beetles of this genus (Meloe) a couple of times now, with no ill effects. 

Female, with oil (and a snack)


The photoshoot concluded with me getting this image of the male, which I just love.  Here’s lookin’ at you, kid:

Heres lookin at you...

 What an awesome start to the bug season!!!

18 responses to “A great (SHINY!) start to the bug season!

  1. Ted C. MacRae April 16, 2011 at 6:45 PM

    Beyond cool!

    I didn’t know the notches in the antennae were used that way – learn something new every day!

    Those last two male portraits? Want!

    • TGIQ April 16, 2011 at 7:35 PM

      I didn’t either, Ted. I guessed they were sexy somehow, but had never heard of or seen this done before. Very few references to the behaviour out there, and fewer pics. I just wish mine had been more in focus 😦
      Which of the two do you think is best? I’m putting a portfolio together for a BugShots student waiver application 🙂 (Any other suggestions would be great too)

  2. Margarethe April 16, 2011 at 7:00 PM

    Neat! And your hands give some scale to it – either my memory is exaggerating (it does that) or our Meloes in AZ are bigger (lots of things are) or your hands are way bigger than mine…

    • TGIQ April 16, 2011 at 7:38 PM

      There are many species, so there are likely larger ones. Actually, the only other female Meloe in my collection is a lot bigger. I’m not sure if it’s just a larger specimen or a different species (haven’t ID’d these two yet).

  3. Katie April 16, 2011 at 9:40 PM

    Wow! This is such a great post for your captures. I love the male antennae C-shaped hooks.

  4. MObugs41 April 17, 2011 at 12:22 AM

    What a wonderful post, I posted about these beetles last spring and have over 30 comments, mostly from people horrified that they have these unique beetles in their yards and want to know how to get rid of them. I love your pictures, and I am with Ted, the last shot of the male is priceless! I love the image of the antennae foreplay! I am one who has a reaction to their excretion. I’ve had their cousins the striped blister beetle and the charcoal gray blister beetle land on me and they will blister me every time, and it HURTS! It takes several days for the blisters to go away too.

    • TGIQ April 19, 2011 at 7:00 PM

      I found the post and read the comments you got…holy smokes! I for one would have LOVED to see a mass swarm of those beetles! I might have kept the dogs inside or on leash while it was happening, but I certainly wouldn’t be complaining! I didn’t know they congregated in the fall…I’ll have to watch for them!
      And that’s two votes for the last picture, so I’m considering it a done deal 🙂

  5. dragonflywoman April 17, 2011 at 1:49 AM

    Oooh! Love the photos and the antenna thing is so cool! i just did a post on insect antennal types and now I’m wondering what the name for that type of antenna is. Do you happen to know? I’m sure it’s got some fancy name…

  6. Seabrooke April 17, 2011 at 10:43 AM

    Neat find! I encounter these from time to time, but always as singles. That’s really cool that you got to see the antennal hooks in action. I, too, love that last photo of the male.

    When I posted about these guys on my own blog, I generally had good reaction from readers, except for one doom-and-gloom commenter who noted, “These beetles and their relatives are HIGHLY toxic to horses! It only takes one little piece of one to kill a horse. One little wing or perhaps one leg will cause an excruciating death to the horse. BEWARE!”

    • MObugs41 April 17, 2011 at 5:04 PM

      Seabrooke, you need to read the blog post I did, seriously the majority of the people who responded were horrified…..they want these beetles gone, period. This is especially true of one individual who has actually posted more than once.

      Horses beware….LOL….there is a chart on the internet that tells how many beetles it would take to kill a horse. It is several hundred for a 200-300 pound horse if I remember correctly. I know it is a significant number anyway. Certainly not “one”..or part of one.

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  9. allthingsbiological April 18, 2011 at 10:39 PM

    Very nice blog entry and set of pictures. What a spectacular way to start the season!!!

  10. Pingback: Bleeding Blister Beetles « 6legs2many

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