No, not a bee eating a bee. Even better! This is a bee-mimicking robber fly, Laphria, feeding on a honey bee. The fly casually alighted next to me in the garden this afternoon, as though it wanted to be photographed with a trophy kill.
Laphria is an exemplary bumble bee mimic. The flies not only look like bumble bees, they move and sound like them as well.
photo details: Canon EF 100mm f/2.8 macro lens on a Canon EOS 7D ISO 400/800, f/14, 1/125 sec diffuse off-camera strobe, handheld overhead
Our front porch has been host to some shiny black Virginia carpenter bees. Earlier this year a couple females chewed burrows in the woodwork in which to store pollen and lay eggs. I had been keeping my eye on the nests to see if I might be able to catch an emerging young bee.
This afternoon, however, I found something even more interesting. Behold!
A carpenter bee nest entrance (lower left) shows signs of activity, but what emerged from pupation were not bees but parasitic Xenox tigrinus flies that had, as maggots, consumed the developing larvae.
A Xenox tigrinus bee fly must have been successful in breaching a carpenter bee’s defenses. Death by parasite is the unfortunate fate of many insects, and bee flies inflict their share of damage on solitary bees whose nests are inadequately protected. Below are a few more photos of the Xenox flies.
The patterned wings of Xenox tigrinus are unmistakable.
The flies let me approach closely while their cuticles hardened.
During the day our showy goldenrod (Solidago speciosa) is visited by the usual sun-loving suspects: bumble bees, sweat bees, hover flies, butterflies, and so on. I was curious about what happens after dark, though, so I just popped out to have a look. It’s nearly as active at night, too, but with a different set of species!
I don't normally think of mosquitoes as pollinators, but our goldenrod was covered with mosquitoes sipping nectar. This one is a male.
Up close, a mosquito's eyes are gorgeous green.
A blister beetle mugs for the camera.
Oh, to have a straw for a mouth!
Canon MP-E 65mm 1-5x macro lens on a Canon EOS 7D
ISO 200, f/13, 1/200 sec, diffuse twin flash
I recently had the opportunity to photograph one of the odder spectacles among insects: a common house fly emerging from its puparium using a giant inflatable head. What’s deal with this strange behavior?
Many millions of years ago, some flies figured out an ingenious way to protect their delicate developing pupae. Instead of shedding their last larval skin and discarding it, as do most insects, these flies (the Cyclorrhapha) retain it as a sort of armor- the puparium– and metamorphose inside. It’s a great example of evolution re-purposing an existing structure for a novel function.
Emerging as an adult inside an unbroken suit of armor has its own difficulties, however. What makes it hard for predators to get in also makes it hard for flies to get out. So they pump their heads full of hemolymph, inflating a balloon-like structure called the ptilinum, and burst their way to freedom using hydrostatic pressure.
Once the fly has emerged the ptilinum deflates back into the head, leaving a characteristic upside-down U-shaped suture.
Canon MP-E 65mm 1-5x macro lens on a Canon EOS 7D camera
f/13, 1/250 sec, ISO 100
(top) background flash; (mid, bottom) diffused foreground flash
Nosodendron californicum – Wounded Tree Beetle
From the Department of Really Obscure Insects, here’s a beetle that few non-specialists will recognize. Nosodendron inhabits the rotting tissue of long-festering tree wounds. These beetles are not rare so much as specialized to an environment where few entomologists think to look. If you can spot the telltale stains of an old wound on the trunks of large trees, you should be able to find Nosodendron. They feed on the microbes- the yeast and bacteria- that grow in the sap leaking from the phloem.
There are, in fact, whole communities of insects associated with tree wounds. Several fly families are found nowhere else. I photographed this odiniid fly drinking from the yeasty slime:
photo details (both photos): Canon MP-E 65mm 1-5x macro lens on a Canon EOS D60
ISO 100, f/13, 1/200 sec, flash diffused through tracing paper