This blog has moved it can be viewed here!

Monday, December 24, 2012

New Fly Species Likes to Party It Up Poolside in Brentwood

I've been scratching my head for a story to tell in this week's blog. At 6:20 last night it hit me! I've never related our Curator of Entomology, Brian Brown's, story of how he discovered a brand new species of fly, right here in Los Angeles! That's right folks, undiscovered fly species are here right under your noses oh and don't forget that one that  flew into your eyeball, maybe that was new to science too, I guess next time you should try to save it!

All kidding aside, there are likely hundreds of new species scientists have never discovered before, right here in L.A.. Brian is famous here at the Museum for saying, "It's just as likely to find a new species to science in L.A., as it is in Costa Rica [where he does a lot of his research], 100%."

All you have to do is look at the numbers. Scientists have described almost a million different species of insects. However, they estimate that there may be anywhere between 9 and 29 million yet to be described! And this is just the insects we're talking about people. A New York Times article that came out last year noted that, "A single spoonful of soil may contain 10,000 different species of bacteria, many of which are new to science."

Back to Brian and his flies. Not everyone believed Brian when he told them he could find loads of interesting and new species here in L.A.. To prove that urban environments can be a frontier of discovery, he set up an experiment.

In a Brentwood backyard, he set up a Malaise trap  a tent-like device that captures flying insects in a large jar of alcohol, a.k.a. "jar of death." One week later he visited the backyard again, collected the jar full of insects, took it back to the lab, and separated out all the phorid flies (that's the family of flies that Brian is a world specialist on).

Poolside Malaise Trap 

"Jar of death"

Sitting at his microscope, Brian pulled out a small (~2mm in length) yellow phorid fly that looked interesting. To identify these flies, you have to dissect them and take them through a special fly key, that asks the you to look for crazy characteristics like laterally flattened hind femoras. So Brian popped the head off the fly and stuck it under the microscope. He took the small fly through the entire key and it didn't match anything this was a brand new species to science, it had never been described before, and it was the very FIRST fly he had looked at! 

Brian's new fly species

Brian pulled out a second fly from the sample and repeated the process. This specimen was similarly small, but brown instead. It also had a characteristic he recognized, the penultimate tarsal segment (a.k.a. second to last segment of an insect leg) was shorter than the last one. This is a characteristic common to a species only known from Europe. Brian took it through the key, and it was indeed the European species. Which, might I add, had never before been recorded in the U.S.!

European flies have a certain je ne sais quoi!

Wait, wait there's more! Seriously, as Brian kept looking he found a third interesting fly in the sample. This fly was a male from the genus Chonocephalus. This fly is from both coasts of Africa, the Seychelles and Canary islands to be exact. This was the very FIRST time it had been discovered outside of that native range! 

Chonocephalus, African phorid fly

So, by looking at only three, seemingly inconsequential flies, Brian had made three scientific discoveries, which have since then been published in well-known journals. Imagine what a month of sampling might uncover, or a year, or what about three year's worth of sampling!

This is exactly what the Museum has funded Brian and a group of other Museum scientists to do. Brian and his crew have dubbed the project BioSCAN (BIOdiveristy Science: City And Nature).

Here's what the BioSCAN website has to say about the project:

"This first-of-its-kind scientific investigation will discover and explore biodiversity in and around one of the world's largest cities: Los Angeles. In three years of sampling from the urban core right out through less-urban surrounding areas, we will focus on the insects, the most diverse group of animals on our planet.

We will discover and document the diversity of insect species living with us in Los Angeles as well as test intriguing hypotheses about how natural areas around the city affect its biodiversity, and specifically, how light in the urban environment is affecting its inhabitants."

Wow! I can't wait to hear what they find.

Wednesday, December 12, 2012

Weevil is as Weevil Does: Total Agave Meltdown

I don't know about you, but I'm not freaking out about the end of the world on December 21. Though, I can tell you "who" should be those agave plants, that's who! So much so, that if I was magically turned into an agave plant tomorrow, I'd totally start partying it up in preparation for total meltdown. Seriously though, agave meltdown is no joke. It's a very real disease that is highly lethal to agave plants and we've just discovered it in the Museum's garden!

It all came about last week. Richard Hayden and Daniel Feldman, the Museum's garden staff, noticed that some of our Agave americana plants weren't looking so hot. Some plants had a few leaves that were wrinkled and beginning to discolor, others were so bad they weren't able to stand up straight anymore. Experimentally, Daniel tugged on a leaf of one of the sick agaves, and surprisingly the entire plant came out of the ground in his hand! What they discovered beneath the surface was not pretty. The roots had become completely unattached and the heart of the plant was a goopy mess of rottenness. Something indeed was rotten in the heart of the Museum Garden!

What sort of "evil" could cause such destruction? Weevil evil, that's what! Upon closer inspection, Richard and Daniel found an aggregation of largish black weevils (about ½ inch long) hanging out in between the plants' leaves. To be specific, they were agave snout weevils, Scyphophorus acupunctatus, and they're proving to be a big problem in the agave world.

Here's what The Desert Botanical Garden in Phoenix has to say about agave snout weevils:

"The females chew their way into the plant base, often between leaf attachments, leaving bacteria (Erwinia sp.) as they go. They lay eggs in the bacteria-infected tunnel. When the eggs hatch, the larvae burrow and eat their way into the rotting heart of the agave. After the grub-like larvae have sufficiently fed and matured they will pupate and emerge as the next generation of adults. The entire life cycle can be completed in six to twelve weeks. Adults are approximately 1/2" in length with dull brown to black stout bodies and characteristic long snouts. The rotund legless grubs are cream color with dark heads.

Most often a snout weevil infestation is not apparent until the damage is severe. As larvae start to feed at the bacterial-infested plant bases and the roots, leaves begin to wrinkle. Shriveling will increase with time and as the plant continues to rot. A putrid odor can develop as bacterial infection creeps through the heart of the plant. In many cases a majority of the leaves collapse to the ground leaving only the central spike of leaves standing. The plant might be loose if wiggled and can easily fall apart. At this stage rescue is unlikely."

When the Museum garden staff realized that this was likely the fate of many of our agaves, they, needless to say, weren't very happy. In just a short week they've wholeheartedly joined the ranks of agave snout weevil haters everywhere. Of course, they have been madly searching for ways to deal with this pest. Most of the literature out there advises continued applications of the insecticide imadacloprid. This chemical is applied around the base of a plant and is taken up via the roots which then imparts toxicity to any insect that happens to eat the plant (including pollinators when they sip nectar). Needless to say, we want to stay away from chemical pesticides as much as possible. Unfortunately, we haven't found any good leads on organic controls, but we'll keep looking.

After hearing all this, being the good friend and coworker that I am, I offered to buy the garden staff a bottle of Mezcal! No, it wasn't to drown their unhappiness in, it was instead to take revenge! The "worm" in the bottom of a bottle of Mezcal is actually very often an agave snout weevil grub. That's right, they could relish in chomping off the head of our weevils' long lost great aunt's nephew or something. Cheers to that!

Daniel removing an infected Agave americana

Daniel dissected the above agave and this is what we found inside!

Close up of agave snout weevil, Scyphophorus acupunctatus.
Even knowing the back story, I still think it's cute.