Posts Tagged: Martin Hauser
Hide the cactus! There's a Mexican cactus fly in our midst.
A large black fly hovers over a Mexican sunflower (Tithonia) in our bee garden and then drops down to sip some nectar. At first glance it looks like a carpenter bee but this one hovers like a syrphid fly, aka flower fly or hover fly.
"Hover fly," I say.
Entomologists Martin Hauser, Lynn Kimsey and Robbin Thorp quickly identified the critter.
Hauser, senior insect biosystematist with the Plant Pest Diagnostics Branch of the California Department of Food and Agriculture, says it's in the genus Copestylum (with over 350 species in the new world) and figured it to be the species, mexicanum, commonly known as the Mexican cactus fly.
Said Lynn Kimsey, director of the Bohart Museum of Entomology and professor of entomology at UC Davis: "Nice, this is actually a kind of syrphid flower fly, better known as a cactus fly. The larvae breed in rotting cactus tissue."
Native pollinator specialist Robbin Thorp, emeritus professor of entomology, also figured it to be a Mexican cactus fly, Copestylum mexicanum. "It's commonly known as a cactus fly (Syrphidae, Tribe Volucellini). "It used to be in the genus Volucella, But now it's in the genus Copestylum."
This fly is not small. It's about 3/4 of an inch long. It lays its eggs in rotting plant material "and they really like rotting cacti," Hauser commented. "As far as I know, they only go into dying cacti and do not attack healthy cacti…. But there is actually not much known about their biology."
The resident cacti expert at our house is worried, showing his best prickly pear expression. He quickly canvasses the yard. Whew! No rotting cacti. All thriving and in good health.
So far, so good...
Black hover fly, aka Mexican cactus fly, sipping nectar from a Mexican sunflower (Tithonia). (Photo by Kathy Keatley Garvey)
Side view of the black syrphid fly, a Mexican cactus flower. (Photo by Kathy Keatley Garvey)
Mexican cactus fly ready to take off. (Photo by Kathy Keatley Garvey)
A freeloader. A moocher. A sponger.
That's the freeloader fly.
A praying mantis is polishing off the remains of a honey bee. Suddenly a black dot with wings edges closer and closer and grabs a bit of the prey.
So tiny. So persistent. So relentless. That's the freeloader fly.
Don't look at the mangled honey bee. Don't look at the hungry praying mantis.
Look at the freeloader fly. Wait a few seconds and you'll see another.
The scene: a camouflaged praying mantis is tucked beneath some African blue basil leaves and the light is fading fast. (You could say I took this image "on the fly.")
Senior Insect Biosystematist Martin Hauser of the Plant Pest Diagnostic Branch, California Department of Food and Agriculture (CDFA) identified these "freeloader flies" as family Milichiidae and "likely the genus Desmometopa." See Wikipedia.
They are so tiny, Hauser says, that the mantids, spiders and Reduviidae (think assassin bugs) "don't bother chasing them away or even trying to eat them."
Hauser pointed out images of freeloader flies from BugGuide.net: http://bugguide.net/node/view/23319/bgimage
And look at all the freeloaders on this prey: http://bugguide.net/node/view/512989/bgimage
Back in March of 2012, agricultural entomologist Ted C. MacRae who writes a popular blog, Beetles in the Bush, posted an image of an assassin bug eating a stink bug. Check out all the flies engaging in what he calls kleptoparasitism--stealing food.
Everybody gets fed. Nobody leaves hungry.
Praying mantis eats a honey bee while a freeloader fly, family Milichilidae, does, too. Another freeloader edges closer. (Photo by Kathy Keatley Garvey)
The freeloader fly is quite persistent. (Photo by Kathy Keatley Garvey)
It's appropriate during National Pollinator Week to remember that.
We spotted this newly emerged green bottle fly (below) nectaring on lavender last week in our yard.
It seemed out of place among the honey bees, leafcutter bees and carpenter bees working the blossoms.
We didn't recognize it as a newly emerged green bottle fly, Lucilla sericata. But fly experts Martin Hauser of the California Department of Food and Agriculture and Terry Whitworth of Washington State University, did.
Family Calliphoridae. Genus Lucilla. Species sericata.
"This looks like a Calliphoridae which just emerged, so the wings are still folded," said senior insect biosystematist Hauser.
Said Whitworth, an adjunct professor of entomology at WSU who maintains the websites birdblowfly.com and blowflies.net: "This is a teneral fly, not fully sclerotized. You can see it just emerged and the wings have still not extended so identification can be tough. However, the shot clearly shows three postacrostichals which almost certainly makes it the common, cosmopolitan Lucilia sericata."
Forensic entomologist Robert Kimsey of UC Davis marveled at the newly emerged fly. "Something dead in your yard?" he quipped.
"No," we said. "But the cat caught a rat the other day. We disposed of it quite quickly." Not the cat, the rat.
'Course, flies aren't known for being pollinators. They're better known--and rightfully so--for disposing of carrion and as the key tool in forensic entomology. They're also used in medical science as maggot therapy. And for art: one of Kimsey's former graduate students, forensic entomologist Rebecca O'Flaharty, coined the term "Maggot Art" (trademarked) and that's one of the activities at the annual UC Davis Picnic Day. Graduate and undergraduate students in the Department of Entomology and Nematology show youths how to dip a maggot in water-based, non-toxic paint, place it on white paper, and let it crawl. Voila! Maggot Art! Suitable for framing...
Everything in life--and death--has a purpose.
Newly emerged green bottle fly nectaring on lavender. (Photo by Kathy Keatley Garvey)
You may have noticed this little floral visitor in your garden.
It might appear to be a bee, a common mistake to the untrained eye or those who think that all floral visitors are bees.
But it's a fly, and flies are pollinators, too!
This fly, from the genus Eristalis, family Syrphidae (hover flies), order Diptera, is probably Eristalis stipator, says fly expert Martin Hauser, senior insect biosystematist with the Plant Pest Diagnostics Branch, California Department of Food and Agriculture.
In its larval form, Eristalis, found in aquatic habitats, is known as a rat-tailed maggot, due to its appendage that resembles a snorkel.
Next time you see this little fly on a flower, you can tell your friends "In its larval stage, it's a rat-tailed maggot."
As they widen their eyes and raise their eyebrows, you can add: "But in its adult stage, it's a pollinator."
Close-up of a fly, genus Eristalis, on a flower. (Photo by Kathy Keatley Garvey)
Flies are pollinators, too! This little Eristalis is nectaring a zinnia. (Photo by Kathy Keatley Garvey)
Side view of an Eristalis. (Photo by Kathy Keatley Garvey)
Ah, the little intricacies of life...
We were walking along a stretch of the coastal town of Bodega Bay when we spotted something we'd never seen before: a bubble on a syrphid fly.
Syrphid flies, also known as hover flies or flower flies, are pollinators, just like honey bees. As floral visitors, syrphids are often mistaken for bees. They're not. They're flies.
But what was the bubble?
Several of our UC Davis entomologists weighed in.
"Weird, I wonder if that's an egg," said one entomologist. "Looks like the ovipositor is extended."
Said another: "If this were a honey bee, I would suggest that you shot your first defecation photo." (Spoken like the true honey bee expert he is!)
And another: "My guess is that droplet is fly (note: brace yourself--here comes the "p" word) poop, composed mostly of digested pollen grains that the flies commonly feed on. If you look closely at the abdomen of these flies, you often see the gut outlined with yellow or orange through the semi-translucent membrane areas of the abdomen due to the pollen they have ingested."
We asked fly expert and senior insect biosystematist Martin Hauser of the California Department of Food and Agriculture's Plant Pest Diagnostic Branch for an I.D. of this syrphid fly. "A female Sphaerophoria," he said.
And, oh, yes, the bubble is not an egg. It's the "p double oh p" word with pollen inside. Hauser pointed out that the eggs are oval and white, so the yellow bubble is not an egg. Check out this photo of syrphid eggs on the bugguide.net website, Hauser said. And here's a image on bugguidenet.com of the syrphid fly ovipositing.
Sounds like a good question for an Entomology 101 quiz...
Or the Linnaean Games...
Syrphid fly (female Sphaerophoria), as identified by senior insect biosystematist Martin Hauser of the CDFA. (Photo by Kathy Keatley Gavrey)
Close-up of "The Girl and the Bubble." See text above for what the bubble is. (Photo by Kathy Keatley Garvey)