I grew up watching Walt Disney’s true-life adventures, where exotic animals from exotic lands paraded across a suburban movie screen for hour after uninterrupted hour. Music woven through Disney’s footage set a mood, a pace, often at the expense of reality. Remember the dancing tarantulas in “The Living Desert?” A foot-stomping fiddle run overlaid what was probably a life or death struggle between two female spiders, converting them into merry, quixotic figurants, blithe beyond belief.
With this not quite in mind the other day, I found a honeybee apparently sipping nectar from a boneset flower that grows in the meadow in front of our house. The bee’s long, tubular tongue extended like a New Year’s party favor into one of the many quarter-inch white blossoms. Pollen dusted her legs. I stepped up to the flower and bent down so that my eyes were in line with the bee’s. The bee, however, remained curiously still, as though suspended from the flower. I looked a little closer.
She was propped up from below the flower by the piercing and sucking mouthparts of two ambush bugs, one fixed to her throat, the other to her abdomen.
Yes, ambush bugs. Though not among the commonly known insects, ambush bugs are found in fields and meadows all across Vermont and New Hampshire from late summer through the first frost. They frequently attack and devour insects many times their own size, with their favorite meals including wasps, bees, flies, and butterflies.
An ambush bug selects a cluster of flowers, settles in, and waits for a potential meal to happen along. My particular boneset hosted light-colored ambush bugs - white and yellow with a hint of green, perfectly camouflaged. Later in August, yellow-brown bugs gather on goldenrod blossoms. Camouflage is a critical part of the ambush bug’s feeding strategy, so finding these insects can be tricky. In general, the adults are between one quarter and one half inch long, have short antennae, and appear somewhat triangular from above because they widen from front to back. From the side, ambush bugs look like miniature praying mantises.
Slow-moving predators, ambush bugs have modified forelegs that serve as powerful grasping organs. Their tibia - the distal end of the foreleg - is a small curved blade like a miniature scythe which snaps back into a groove on the short, thickened femur. Both tibia are armed with teeth. The entire leg looks like Popeye’s arm - thin on either end, swollen in the middle.
When a bee lands near an ambush bug, the bug grabs it by any available body part: tongue, foot, antenna, or wing. Locked on, it probes the angry, thrashing bee, finds a soft spot, usually between the head and thorax or along the abdomen, and then inserts its hollow beak, pumping digestive enzymes that slowly make soup of the bee’s innards. When the ambush bug is through feeding, all that is left of its victim is a dried husk.
As I watched the ambush bugs drain the honeybee, three parasitic flies, smaller than blackflies, settled on the bee’s abdomen. They came for a free lunch. When the flies were done, they lumbered off, their transparent bellies swollen with pre-digested bee juice. Twenty minutes later, the ambush bugs, too, were sated. They disappeared back into the cluster of flowers.
The easiest way to find an ambush bug is to walk into a meadow at this time of year, look for flowering boneset, goldenrod, or milkweed, and examine the ground beneath the flowers for the dried husks of bees, wasps, or butterflies. Once you find these table scraps, carefully examine the underside of the flowers themselves for the well concealed ambush bugs. Don’t worry – though they could star in an insect horror movie, ambush bugs don’t pose a danger to human hands.
I had approached some flowers in my meadow as many of us approach nature itself, expecting a benign and beautiful true-life adventure: “Pollination in a Wet Meadow.” Instead of a thirsty pollinator sipping nectar and inadvertently pollinating a flower, I found a hapless cadaver. The adventure was true to life, and beautiful in its own way, but the script was by Poe, not Disney. Like the bee, I had been ambushed by my own expectations.