Tuesday, July 20, 2010

There are a gazillion insect stories in the naked city; this is one...

Long, long ago…. I got rid of the tomatoes, and planted my community garden plot with milkweeds and goldenrods. I had decided to feed not myself, but the BEETLES. I especially hoped to attract two cerambycids: locust borers (Megacyllene robiniae), which mate on goldenrod but lay their eggs on locusts, and milkweed beetles (Tetraopes tetrophthalmus), which feed on--you guessed it--milkweeds.

During the next year or two, I actually saw the occasional locust borer.  But the milkweed took over within a few years, and while it attracted a number of other milkweed feeders, I had pretty much lost all hope of attracting Tetraopes tetrophthalmus... until just last week, 15 YEARS LATER, when one individual arrived! 

First I noticed some unusual feeding damage;
many of the leaves were missing their tips. 
Then Mary T. spotted the culprit... 
and  documented its presence with her Iphone.
Can you see it? The long antennae gave it away.
I hurried back the next morning, hoping to catch it feeding.
But T. tetropthalmus (so called because the upper lobes of its eyes 
are completely separated from the lower lobes) 
was NOT pleased to be disturbed, 
and flew off to take refuge amongst the rose prickles.
I returned to my milkweeds to check out the feeding damage 
more closely. After all, not just any insect can feed on milkweed, 
with its gooey latex and toxic cardiac glycosides...

It turns out that "Tetro," like numerous other insects that eat 
latex-producing plants,  avoids the mess by slicing right 
through the leaf midrib! This diverts the flow of latex, 
allowing the crafty engineer to feed with near-impunity. 


  1. Whenever I hope to attract cerambycids I splash on some cologne and wear tight pants but planting milkweed is also effective.
    These beetles and your photographs of them are beautiful. Thank you for magnifying a world I would normally have never noticed.
    BTW, my favorite beetle is Popillia japonica, commonly known as the Japanese beetle with an amazing iridescent copper-colored elytra and green thorax and head. They are clumsy fliers and easy to catch, I used to admire them in jars as a child. X Paulo

  2. Dear Amy,
    Congratulations, I really like the design and color of your blog. I do not like bugs as you well know. Please come to my apartment at once with your net and arsenic as I have another waterbug running amok in my apartment.
    Your friend and neighbor,

  3. Hi Paulo,

    Once I tried to attract cerambycids in Peru by baiting traps with vanillin, the chemical that gives vanilla its aroma. My baggy field clothes ended up reeking of vanilla (better, I guess, than sweat). When I walked through the forest I found myself dive-bombed NOT by cerambycids, but by big euglossine orchid bees! The males collect aromatic compounds as part of their lek-forming habit.

    Beetles have a reputation of being clumsy fliers. Many of them are not clumsy at all, but scarabs (the family including the Japanese beetle) definitely are. At dusk in the tropical rain forest, huge dung beetles (also scarabs) sometimes collide with me; they plummet to the ground, take back to flight, and do the same thing all over again!

    Cheers, Amy B.

  4. Hi David,

    I'm afraid that we have to credit the template makers for the improved aesthetics of blog #2. Sorry, you know my time-tested water bug strategy-- trap under a pan and wait. Jack and Pipsqueak had the great thrill of chasing a house centipede the other day... but being boy cats it was all play! The females, as you undoubtedly know, go in for the kill.

    Your friend and (albeit useless) neighbor,
    Amy B.

  5. I am very sorry indeed to hear that you were repeatedly hit by huge dung beetles. Life is not always what we imagined it would be.

  6. You're telling me... One can only hope that life's dung beetles are no longer covered in dung.