entomology
awild | May 11, 2008
Rose Aphids - Macrosiphum rosae
Tucson, Arizona
It's fair to say that without the encouragement of my mother, who allowed all manner of newts, snakes, caterpillars, tadpoles and ants into the house, I would not have gone on to become a biologist.
Thanks Mom, and happy mother's day!
photo details: Canon MP-E 65mm 1-5x macro lens on a Canon 20D
f/13, 1/250 sec, ISO 100, twin flash diffused through tracing paper.
awild | May 9, 2008
Amphizoa insolens - trout stream beetle
California
Amphizoa are among the more enigmatic insects I've photographed. These dime-sized beetles are found only in the mountains of China and western North America, a disjunct distribution paralleled by a number of interesting taxa, including the giant redwoods. All six species are predaceous and aquatic, living in debris and under stones in fast-running creeks. Because adults have a morphology suggestive of the terrestrial ground beetles, some researchers have proposed that Amphizoa represents an evolutionary transition between terrestrial and…
awild | April 29, 2008
If you're having trouble filling that bare wall over your desk, the Bohart Museum of Entomology has just the thing: a new line of insect posters. The invasive ant poster above was designed by Fran Keller from auto-montage images by Eli Sarnat, Jasmine Joseph, and Anna Lam.
awild | April 25, 2008A few of the many species described by Roy Snelling:
Myrmecocystus tenuinodis Snelling 1976
Stenamma dyscheres Snelling 1973
Neivamyrmex wilsoni Snelling & Snelling 2007
awild | April 21, 2008
Areolate
In 1979, Rick Harris wrote a definitive paper illustrating the various terms used by taxonomists to describe the intricate patterns on the insect exoskeleton. His guide is tremendously helpful to those of us who struggle to decide if those ridges on the head of an ant are strigate or costate. Via Sifolinia, I now see that Harris's illustrations are available online:
A Glossary of Surface Sculpturing
Incidentally, Rick was the guy who taught me how to use a Scanning Electron Microscope, although at this point it'd be a minor miracle if I remembered any of it.
awild | April 14, 2008
I can't imagine a more unpleasant way to go. This poor oleander aphid (Aphis nerii) has its innards sucked out by a hoverfly larva.
photo details: Canon MP-E 65mm 1-5x macro lens on a Canon 20D
f/13, 1/250 sec, ISO 100
MT-24EX flash diffused through tracing paper
levels adjusted in Photoshop.
awild | April 13, 2008
The Argentine Ant (Linepithema humile), a small brown ant about 2-3mm long, is one of the world's most damaging insects. This pernicious ant is spreading to warmer regions around the world from its natal habitat along South America's Paraná River. Linepithema humile can drive native arthropods to extinction, instigating changes that ripple through ecosystems. In California, horned lizard populations plummet. In South Africa, plant reproduction is disrupted. Worldwide, the Argentine ant is a persistent house and crop pest. This is not a good ant.
My Ph.D. dissertation, completed a few…
awild | April 11, 2008
Temnoscheila Bark-Gnawing Beetle, Arizona
Trogossitidae
This colorful insect arrived to a blacklight in my backyard a couple of years back, right when I first moved to Tucson. Previously I'd encountered Temnoscheila only under the bark of dead trees, where they apparently prey on the larvae of other beetles. I've always wondered why a beetle that spends most of its time secluded in the dark would need such a brilliant metallic sheen, if the color serves a purpose or is just a spandrel. In any case, this beetle ended up donating its body to science. It is one of several representative…
awild | April 7, 2008
Deserts are difficult places to live for more reasons than just drought and heat. During dry seasons deserts are relatively inactive, and there's not much around for animals to eat. To survive times of dearth, several lineages of desert ants have taken to harvesting plant seeds in the brief periods of bounty that follow rains. If stored properly, grains keep for years and can provide the colony with ample resources during times when the deserts are dry.
This past week the stubby carpet of spring grasses in our normally barren back yard started going to seed. After months of dormancy,…
awild | April 4, 2008
Epicauta pardalis - spotted blister beetle
Tucson, Arizona
Here's a beetle so toxic it can kill a horse. The horse doesn't even need to ingest the beetle, it just needs to ingest something that the beetle bled on. Blister beetles produce the defensive compound cantharadin- the active ingredient of the aphrodesiac Spanish Fly- which they reflex-bleed out their joints when threatened:
photo details (top) Canon 100mm f2.8 macro lens on a Canon 20D
f/13, 1/250 sec, ISO 100, indirect strobe in white box.
(bottom) Canon MP-E 65mm 1-5x macro lens on a Canon 20D
f/13, 1/250 sec, ISO 100, flash…
awild | April 3, 2008Back in 2002 when I used the Nikon Coolpix 995 for everything, I would occasionally play around with the camera's very basic video mode. The 995 made small, grainy movies without sound, and most of the videos I took are, well, pretty bad. But the camera had impressive macro abilities, which meant it could shoot ants close-in. Here's a movie of a Dinoponera from the Mbaracayú Forest Reserve in Paraguay:
awild | April 2, 2008
Acromyrmex versicolor - the desert leafcutter
Here's the original:
photo details: Canon MP-E 65mm 1-5x macro lens on a Canon 20D
f/13, 1/250 sec, ISO 100
MT24-EX twin flash diffused through tracing paper
Photoshop modification (top photo): desaturated yellows
increased contrast, burned edges, and added noise
awild | March 31, 2008via Google Trends. Blue is ants, red is beetles:
Ants win, even in the face of the beetles' 20-fold species advantage.
That seasonal pattern is striking, no?
awild | March 19, 2008
In our front yard we've got a busy nest of Pogonomyrmex rugosus seed harvesting ants. Warming weather brought them out for the first time last week, and every now and again I go out to see what they're up to. Lots of digging, it seems.
Pogonomyrmex is greek for "Bearded Ant", named 150 years ago by Austrian myrmecologist Gustav Mayr for the thick brush of hairs on the underside of the head. Entomologists affectionately refer to these ubiquitous desert insects as "Pogos". What does the beard do?
It's a construction tool, and one that is especially helpful in dry, sandy climates. As anyone…
awild | March 13, 2008
DEET is the main ingredient in most insect repellents. Slather it on and it's like magic; the mozzies just fly on by. Nothing else is as effective.
In spite of its utility, DEET is pretty nasty stuff. Depending on where you are in the world, you might be healthier just letting the bugs bite. It melts plastic, and I don't even want to think about what it does as it seeps into skin.
So, I was relieved this afternoon to read a report in this week's Science detailing the biochemical secrets behind DEET. Apparently, the chemical blocks an odor co-receptor called OR83b on insect antennae. When…
awild | March 9, 2008
Strumigenys louisianae stalking a springtail
Tucson, Arizona
Non-native species should make a naturalist's skin crawl, but these ornate little trap-jaw ants are a guilty pleasure. Strumigenys louisianae is among the most widespread of the miniature trap-jaw ants, occurring naturally from the southeastern U.S. to northern Argentina. The desert climate in Tucson is too dry for Strumigenys, but they persist in lawns, gardens, and other places in town where irrigation raises the moisture levels. No one knows when or how they arrived, but it is likely the founding colonies stowed away in…
awild | March 7, 2008
Apteroloma caraboides (Agyrtidae) - Snowfield Beetle
California
Why would I waste a prime Friday Beetle Blogging slot on such a drab little beetle? Because Apteroloma caraboides does something really cool. Really cold, even. This species inhabits the edges of high-altitude snowfields. They are found in places like these, in the high Sierra Nevada:
Snowfields are an inhospitable environment for an insect, but one that offers animals with good cold tolerance a unique way to make a living. Apteroloma caraboides cruise the easy pickings of less hardy creatures that fall onto the snow…
awild | February 29, 2008
Out today is a preprint version (subscription only) of Corrie Moreau's Pheidole phylogeny. At first glance this seems a nice piece of work: the evolutionary history of one of the world's most diverse ant genera inferred from 140 species and 5 genes.
This is some extremely cool ant evolution research, and the first salvo from the nascent Pheidole working group. Once I get a chance to digest all 50+ pages I'll post the highlights.
source: Moreau, C. S. 2008. Unraveling the Evolutionary History of the Hyperdiverse Ant Genus Pheidole (Hymenoptera: Formicidae). Molecular Phylogenetics and…
awild | February 22, 2008
The smallest insect I've ever photographed made the cover of the scientific journal Genetics this week. Encarsia pergandiella, an aphelinid wasp not even a millimeter long, was the subject of a study by Perlmann, Kelly, and Hunter documenting the reproductive consequences of infection by bacterial parasite.
The wasp lab is downstairs from ours, so it wasn't much trouble to schlep my equipment over for an afternoon session. The goal was to create a set of images to submit to the journal as potential covers, and I was more than happy to have the opportunity to shoot these charismatic little…