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Posts Tagged: flower fly

Rats!

This rat-tailed maggot will become a drone fly, Eristalis tenax. (Photo by Kathy Keatley Garvey)
Rats!

How many times have you encountered a "honey bee" on the Internet, in a book, magazine, newspaper or other publication, and found a syrphid fly misidentified as a honey bee?

It's truly amazing how often syrphid flies are mistaken for honey bees.

Take the Eristalis tenax, a European hover fly quite established in the United States.

And quite "established" as a honey bee.

It's a syprhid, in the family Syrphidae; in the subfamily, Eristalinee; in the tribe Eristalini; in the subtribe Eristalina; and in the genus, Eristalis.

It's typically called a drone fly (it's about the size of a male honey bee or drone) but some folks also call it a hover fly, a flower fly or a syprhid.

No matter what you call it, it's a fly, not a bee.

Now to the "rats" part.

Their larva is known as a rat-tailed maggot. Its long tail-like structure resembles that of a rat or a mouse.  Sometimes it looks like a corn dog with a tail. Or a butterscotch-colored lollipop with a tail.

Rat-tailed maggots live in such habitats as sewers, manure pile pools, drainage ditches and other badly polluted areas. Which is probably why you don't see them. (And if you did, you'd know it wasn't a corn dog with a tail.)

But in the adult stage, they're pollinators. They go where the honey bees go.

You'll find the adult drone flies nectaring on such flowers as lavender, catmint, daisies, sunflowers and yarrow, and hear people exclaiming "Look at the bees!"

I'm waiting for someone to say "They used to be rat-tailed maggots." 

A drone fly, Eristalis tenax, on a Shasta daisy at the Luther Burbank Home and Gardens.. (Photo by Kathy Keatley Garvey)
A drone fly, Eristalis tenax, on a Shasta daisy at the Luther Burbank Home and Gardens.. (Photo by Kathy Keatley Garvey)

A drone fly, Eristalis tenax, on a Shasta daisy at the Luther Burbank Home and Gardens. (Photo by Kathy Keatley Garvey)

A drone fly,Eristalis tenax, on yarrow at the Luther Burbank Home and Gardens. (Photo by Kathy Keatley Garvey)
A drone fly,Eristalis tenax, on yarrow at the Luther Burbank Home and Gardens. (Photo by Kathy Keatley Garvey)

A drone fly, Eristalis tenax, on yarrow at the Luther Burbank Home and Gardens. (Photo by Kathy Keatley Garvey)

Close-up of a drone fly, Eristalis tenax. (Photo by Kathy Keatley Garvey)
Close-up of a drone fly, Eristalis tenax. (Photo by Kathy Keatley Garvey)

Close-up of a drone fly, Eristalis tenax. (Photo by Kathy Keatley Garvey)

Posted on Monday, June 9, 2014 at 5:26 PM

Hovering in the Wind

The 40 mile-per-hour howling wind didn't seem to bother the syrphid fly, aka hover fly and flower fly.    

It clung to a blossom on the tower of jewels, Echium wildpretii, and proceeded to nectar. Its wings sparkled in the morning sun.

This is a pollinator and one that's often mistaken for a honey bee.

A honey bee it isn't. It's a fly.

If you want to read more about them, be sure to check out entomologist Robert Bugg's UC ANR publication, Flower Flies (Syrphidae) and Other Biological Control Agents for Aphids. Click on the link for access to a free 25-page PDF.

Syrphid fly nectaring on tower of jewels, Echium wildpretii. (Photo by Kathy Keatley Garvey)
Syrphid fly nectaring on tower of jewels, Echium wildpretii. (Photo by Kathy Keatley Garvey)

Syrphid fly nectaring on tower of jewels, Echium wildpretii. (Photo by Kathy Keatley Garvey)

Syrphid sparkles in the early morning sun. (Photo by Kathy Keatley Garvey)
Syrphid sparkles in the early morning sun. (Photo by Kathy Keatley Garvey)

Syrphid sparkles in the early morning sun. (Photo by Kathy Keatley Garvey)

Posted on Thursday, May 2, 2013 at 9:30 PM

The Girl and the Bubble

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.

Mystery solved!

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)
Syrphid fly (female Sphaerophoria), as identified by senior insect biosystematist Martin Hauser of the CDFA. (Photo by Kathy Keatley Gavrey)

Syrphid fly (female Sphaerophoria), as identified by senior insect biosystematist Martin Hauser of the CDFA. (Photo by Kathy Keatley Gavrey)

Close-up of
Close-up of "The Girl and the Bubble." See text above for what the bubble is. (Photo by Kathy Keatley Garvey)

Close-up of "The Girl and the Bubble." See text above for what the bubble is. (Photo by Kathy Keatley Garvey)

Posted on Monday, August 20, 2012 at 9:56 PM

Not a Good Day for a Flower Fly

It was not a good day for a flower fly.

A flower fly, aka syrphid fly, dropped down in a patch of pink roses at the Häagen-Dazs Honey Bee Haven at UC Davis today to sip nectar.

It was a pink-rose kind of day. 

Not for the flower fly, though. A crab spider, lying in wait, pounced.

The battle ended quickly, but the syrphid-fly feast was not to be. Not today. The predator dropped its prey.

You can see lots of predator-prey action  at the Häagen-Dazs Honey Bee Haven, a half-acre bee friendly garden located next to the Harry H. Laidlaw Jr. Honey Bee Research Facility on Bee Biology Road, west of the central campus.

It's open from dawn to dusk. Admission is free for all--including predators and their prey.

Crab spider nails a flower fly in the Haagen-Dazs Honey Bee Haven. (Photo by Kathy Keatley Garvey)
Crab spider nails a flower fly in the Haagen-Dazs Honey Bee Haven. (Photo by Kathy Keatley Garvey)

Crab spider nails a flower fly in the Haagen-Dazs Honey Bee Haven. (Photo by Kathy Keatley Garvey)

Crab spider loses its prey and heads down a stem. (Photo by Kathy Keatley Garvey)
Crab spider loses its prey and heads down a stem. (Photo by Kathy Keatley Garvey)

Crab spider loses its prey and heads down a stem. (Photo by Kathy Keatley Garvey)

Posted on Friday, May 27, 2011 at 8:44 PM

Why Organic Farmers Love Hover Flies

“If you were an aphid on a head of lettuce, a hoverfly larva would be a nightmare. They are voracious eaters of aphids. One larva per plant will control the aphids.”

That's what organic researcher Eric Brennan of the Agricultural Research Service (ARS), U.S. Department of Agriculture, told reporter Jim Robbins in a recently published New York Times article.

Headlined "Farmers Find Organic Arsenal to Wage Wars on Pests," the news story drew attention to why natural enemies are "key to the organic approach."

Brennan is based in Salinas Valley, known as "The Salad Bowl of America." It's reportedly where 80 percent of Americans get their greens.

And it's where the lettuce aphid gets its lettuce. 

To help resolve the problem, organic farmers are planting alyssum in their lettuce beds. Hover flies "live in the alyssum and need a source of aphids to feed their young, so they lay their eggs in the lettuce," Robbins wrote. "When they hatch, the larvae start preying on the aphids."

Could be that the "salad days" are over for the aphids--thanks to Brennan, alyssum and hover flies.

Hover Fly
Hover Fly

HOVER FLY working a flower in the Haagen-Dazs Honey Bee Haven at the University of California, Davis. The larvae of hover flies are voracious aphid eaters. (Photo by Kathy Keatley Garvey)

Close-Up
Close-Up

CLOSE-UP of hover fly, also known as a syrphid fly or flower fly. (Photo by Kathy Keatley Garvey)

Posted on Thursday, December 16, 2010 at 8:12 PM

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