diptera

A Bee Eating Another Bee?

Laphria4

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.

Laphria3


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

Attack of the killer bee flies

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.

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.
Hanging out.

The Night Shift

A moth sips goldenrod nectar after nightfall

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!

photo details:
Canon MP-E 65mm 1-5x macro lens on a Canon EOS 7D
ISO 200, f/13, 1/200 sec, diffuse twin flash

An inflatable head

The amazing ptilinum of the common house fly

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.

puparium

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.

breaking free!

Once the fly has emerged the ptilinum deflates back into the head, leaving a characteristic upside-down U-shaped suture.


photo details:
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

Slurp

A long-tongued horse fly drinks from a flower in Arizona's Chiricahua mountains
A long-tongued horse fly takes a sip of nectar in Arizona's Chiricahua mountains.
100% crop of the same image.
100% crop of the same image.

photo details: Canon 65mm MP-E 1-5x  macro lens on a Canon EOS 20D
ISO 100, f/13, 1/250 sec, flash diffused through tracing paper

An intimate moment

rhagoletis11
Rhagoletis fruit flies mating, Arizona

photo details: Canon MP-E 65mm 1-5x macro lens on a Canon EOS 20D
ISO 200, f/11, 1/200 sec, backlit by handheld strobe.