Insects at Parkside

I’m never sure what we find when we go out on the grounds at Parkside Middle School.  Every week I am there as part of their after school program and yesterday was a glorious day to be outside.

Lately, our trips outside have involved binoculars, so yesterday I decided we’d go with hand lenses and bug boxes and look for insects.

There’s a small patch of tall grasses and weeds along the trail next to the school and that was our destination.  A lovely old tree is slowly decaying away here, lying on its side.  One of the kids kicked a large section of one side off and we all poked around in it looking for interesting things.  We found a praying mantis egg case, and lots of sow bugs, as well as a few spiders.  But THE find of the afternoon was this beautiful beetle:

eyed elater

It’s hard to tell from this photo (which I had to take with my phone since I did not bring my camera along), but this beetle was about 1.25″ long.  And with those wonderful eye spots on its thorax, it is a spectacular sight to behold.

So, what is it?  It is an Eyed Elater, Alaus oculatus, which is one of the click beetles.  Click beetles are so named because they have this “peg” underneath them that “projects backwards from the underside of the prothorax against a peghold or catch.”  (From Insects, Their Natural History and Diversity by Stephen Marshall.) When the beetle is pestered, it will flick this peg, making the insect flip into the air with a loud click!  It is startling and will likely cause a predator to jump, allowing the beetle a chance to escape.  This one did not take advantage of this strategy – it just lay there, hoping we’d leave it alone.

These handsome beetles are found in decaying wood, where their larvae feed on the larvae of other wood-boring beetle larvae and the larvae of other insects.  None of my insect books mention what the adults eat.

Eyed Elaters are widespread in the east, but are not abundant (according to the Kaufman Field Guide to Insects of North America).  So how lucky we were to find one!

On the way back to the school, my eyes were drawn to this bright white ball of cotton on the grass.   It looked like the end of a giant Q-tip, but I knew it was not man-made when I picked it up, for it was attached to the grass blades.

myster coccoon bundle of braconid wasp coccoons

At a loss for identifying this on my own, this morning I took photos and sent them in to BugGuide.Net, the gurus of insect ID.  In less than five minutes I had an answer:  a bundle of braconid wasp cocoons.

HM!  How ’bout that!  I’m not sure what I thought it was, beyond a cocoon of some sort, but I don’t think “wasp” was in the running.

Braconids are parasitic wasps – they lay their eggs on caterpillars, and the larvae often eat the caterpillars from the inside out.  Some pupate inside their host, while others, like the ones above, pupate away from the host.  This particular species attaches its colonial pupal cocoon to vegetation.

Braconids are good to have around – they parasitize things like the tomato hornworm, the bane of many a gardener around here.  Of course, we are less thrilled when we find them on caterpillars we like, but even so, they perform an important role in the world, so we want them around.

As for the bundle pictured above, at the moment it is in a jar in my office.  If/when the young wasps emerge, I’ll be sure to post photos so you can all enjoy the completion of the cycle.

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About Dahlem Center

The Dahlem Center is a non-profit nature center/environmental education center located on almost 300 acres just south of the city of Jackson, Michigan. The Center is one arm of the Dahlem Conservancy, which includes land conservancy and stewardship in its mission.
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