A new type of ant-decapitation in phorid flies!

Dohrn longi plateOkay, I literally have been waiting for years to write this story! Now it is published, and you can read about our amazing (at least to me) discovery.

Most phorid flies that decapitate their hosts do so by injecting an egg into the host ant; after hatching from the egg, a larvae feeds in the head, eventually causing the head to fall off, sometimes before the rest of the body stops moving.

In species of the Dohrniphora longirostrata group, however, the female flies are attracted to injured Odontomachus ants, which they decapitate themselves, and haul off the head to feed on its contents or to lay an egg. We have seen this in several countries, and on many occasions, so there is no doubt in my mind that this is a specific behavior to these flies. They are not attracted to injured ants of other types, only Odontomachus.

Here is some video of the action!

(video by Kate Lain)


No, not the operating system. I’m talking about physical windows in a building. If some doors, other windows, or even the whole side of the building are open, windows can be fantastic places to collect flies. Like most dipterists, I go right to the windows of any building I am in, to see what is there. Sometimes, people look at me as if I am crazy, but I forgive them because they just don’t realize how cool flies are yet (top to bottom, a ropalomerid, stratiomyid, and tababid).




Wendy Porras and I just got back from La Selva Biological Station in Costa Rica, where half of the dining room is wide open, while the other half has screened windows throughout. We found a lot of extremely photogenic flies, some of which I show here. We put them in a more pleasing background than screening, wrangled them to sit still, and got the shots we wanted. A little honey on the leaves helped, as some flies were apparently hungry after several hours of banging their heads against metal cables.

Barber-ian triumph

My old friend and colleague Kevin Barber is visiting us in Los Angeles to help out with our Diptera collection and to do a little collecting. Kevin works on a family called Anthomyzidae, which are slim, long-winged flies usually associated with plants upon which they innocuously feed. Two species that he is looking for are known from Morro Bay (California), so we took him up to the Central Coast to find them.


I am happy to report that he found them both!


One is a species called Stiphrosoma vittatum with prominent stripes on its body, whereas the other is an undescribed Anthomyza species. Both were found together in a streamside forest near Cambria, CA, where the indicator plant that Kevin was seeking, Equisetum telmateia, grows OLYMPUS DIGITAL CAMERAabundantly (thanks to local bird expert Jim Royer who suggested the site). One more day of collecting remains, and Kevin’s goal is to collect many more specimens, especially of the Anthomyza, of which so far he found only two specimens.




Finding such otherwise unknown or poorly known species of tiny (up to 3 mm long) flies is tougher than finding a needle in a haystack: at least you know where the haystack is! I am constantly amazed at the skill and knowledge of taxonomic experts like Kevin Barber.

The Most Beautiful Fly in the World

I know that this might be controversial; after all, people generally either don’t think flies have any redeeming qualities (never mind “beauty”), or more likely for readers of this blog, have their own ideas of what constitutes a gorgeous fly.
silver strat zerenea
I submit, however, that this amazing silver male stratiomyid (soldier fly) from Costa Rica is the most beautiful fly in the world. It moves around on the underforest leaves like an animated drop of quicksilver, flashing in the tropical sun. It is not garish, like some of the gaudy calyptrates I have seen (see below), but has a pure beauty in its clean, sleek metallic cover. Just in case you find this boring, it also has a scutellum decorated with spines, like the crown of royalty.

The name of this creature is Artemita aurata (Macquart), and it was described in 1846, so it is not anything new, but it deserves “rediscovery” by lovers of biodiversity everywhere.

Don’t agree with me? Let’s hear your nominations!

OLYMPUS DIGITAL CAMERAA gaudy calliphorid from Australia: a runner-up to the world’s most beautiful fly

Moving to micro four-thirds

holding camera

My new Olympus OMD EM1 camera with 60 mm macro lens. Look how small it is!

Insect photography can be demanding, time-consuming, and expensive. It can also be heavy, lugging around a big SLR camera, a couple of lenses, flash, batteries, and other equipment necessary to capture high-quality images. Often, when I am in the field, I carry a heavy backpack of camera equipment plus my collecting gear on the first day, but subsequently leave the camera at home because it is just too much stuff.


Honey bee – sharp!

On a recent trip, miserable because of the heat of the tropics and the weight of my camera gear, I vowed I was finished with full-sized SLRs. I decided I would follow my technician Wendy Porras in moving to Olympus micro four-thirds (mft) technology. After all, these mirrorless cameras are half the weight, size, and price of a SLR, but have amazingly good image quality. The attached photo of honey bee won’t win any prizes, but you can see how sharp the images can be (an exceedingly important consideration for those of us photographing small flies). My new camera also has in-body image stabilization, which gives me a higher percentage of successful, non-blurry images.

Best of all, the camera is small enough to fit in a much smaller bag, and won’t be left behind when I need it in the field.

From now on, it is mft for me.

Forty-five seconds of fly swarming

One of my favorite museum exhibits is the round ceiling tank at the Monterey Bay aquarium, where a huge school of silver-colored fish swim in an endless circle. It is hypnotic, fascinating, and strangely calming.

Watching flies in a mating swarm can be that way too. Usually, it is a group of male flies we see, all jockeying for the best position in the air. Presumably, this allows arriving females to recognize those that are superior and choose the male in the “best” position for the one with which they will mate.

Thinking of the Monterey Bay experience, I wanted to document a fly mating swarm, and finally got the chance this summer. A group of empid flies (also known as “dance flies”) were flying in a brilliant shaft of light against a dark conifer background, perfect for my purposes. Let me know what you think of the result!


Flyobsession back online

After transferring from WordPress.com to my own site, flyobsession is back! Look forward to more stories and photos of our two-winged friends.

Pictured here is a male Adelopteromyia, a common phorid fly from the ZADBI project in Costa Rica (photo by Inna Strazhnik). The females of this genus are brachypterous (have reduced wings) and are found in army ant colonies.


ps. This image looks much better full size- click on it to see.

Diptera Blitz wrap-up

EOL micropezidOf course, our event was a tremendous success. Some highlights:

– bat-netting by Carl Dick got us streblid records, bird-netting by Kimball Garrett got some hippoboscids.

– Carlos de la Rosa (the Director of the La Selva Biological Station) joined the team, working on chironomid midge pupal exuviae

– Michael Turelli, professor of genetics at UC Davis and (at least on this trip) amateur drosophilid collector gave a stunning talk about using the intracellular bacterium Wohlbachia to eliminate dengue

– the final event, a barbeque, featured a short film about the week by LACM videographer Edgar Chamorro.

Some photos follow, including a group photo of nearly all participants. These photos help portray not only the enjoyment, but also the dedication of the team to document as many Zurqui flies as possible. The results of their efforts will appear soon on this website.

Yes, nearly all these people came to Costa Rica to study flies! (click photo for larger view)

Diptera blitz kimball
LACM ornithologist Kimball Garrett releasing a bird after checking it for hippoboscids (bird louse flies)

Manuel Art Brian
Manuel Zumbado, Brian Brown, Art Borkent: three dipterological amigos