The Mesmerizing Eyes of Eristalinus taeniops

April 10, 2014

By Emily Hartop This week, we bring you a visual treat from BioSCAN's Principal Investigator, Curator of Entomology, and Photographer Extraordinaire, Dr. Brian Brown.

Photo by Dr. Brian Brown

Photo by Dr. Brian Brown By Emily Hartop This week, we bring you a visual treat from BioSCAN's Principal Investigator, Curator of Entomology, and Photographer Extraordinaire, Dr. Brian Brown. His beautiful photo (above) of Eristalinus taeniops was taken in the NHMLA's Nature Garden, home to BioSCAN Site #1. This species is commonly known as the Stripe-Eyed Flower Fly, from the family Syrphidae, commonly called Flower or Hover Flies from their habit of hovering hummingbird-style over flowers in search of nectar. Although syrphid flies are quite common in the BioSCAN traps, this particular species has not yet been captured by our project. Dr. Jim Hogue, also an entomologist and photographer as well as a BioSCAN site host, speculated that this fly is simply too strong a flier to be easily corralled into death by Malaise trap. The entomological equivalent of "The Ugly Ducking", the larvae of the stunning Stripe-Eyed Flower Flies are filth-dwelling Rat-Tailed Maggots. The "rat tail" is actually a telescopic breathing tube that allows larvae to mature in stagnant, and often polluted, water (and other moist substrates lacking in oxygen). The tube allows them to "snorkel" at the surface to breathe. Also on the list of this fly's unsavory larval habitats, rare cases of human intestinal myiasis — where larvae develop inside the human gut — have been documented for this group. The breathing tubes of the maggots, in this case, would be located in close proximity to their host's anus to allow them to breathe. Despite their distasteful beginnings, the Stripe-Eyed Flower Flies certainly turn out to be magnificent adults. Not only are they amazing honeybee mimics, but their striped eyes are absolutely hypnotizing. This pigmentation may serve an optical purpose, but more research must be done on this group before conclusions are to be made.

Photo Copyright by Dr. Jim Hogue (used with permission)

Photo Copyright by Dr. Jim Hogue (used with permission) If you haven't seen the Stripe-Eyed Flower Fly buzzing around your yard, keep looking! The first California record for the species was in 2006 from Orange County. Three years later only a single specimen was found when Dr. Brown and Dr. Hogue worked on local Flower Flies for the booklet "Flower Flies of Los Angeles County". That single specimen was from Dr. Hogue's Eagle Rock backyard, which is now a BioSCAN site! Above, you can see another beautiful photograph of this species, this one taken by Dr. Hogue. Originally, Eristalinus taeniops was from southern Europe, Africa and the Middle East. Introduced species can sometimes create issues for native flora and fauna, but it doesn't appear that Eristalinus taeniops is creating any problems. We're glad, because it sure is a stunning addition to our Flower Fly fauna!

(Posted by: Emily Hartop)


Beautiful pictures! Do all Syrphid flies begin life as "Rat-Tailed Maggots" - or is that just the Stripe-Eyed Flower Fly?

I live in Rancho Santa Margarita, & I saw one of these in mid-November in my front yard.

I saw one today it worried me it looked weird i could tell it wasnt a bumble bee. It is just a fancy fly? Or does it make honey?

Not all syrphids begin life as charming "Rat-Tailed Maggots" — it is a characteristic of the tribe Eristalini within the family.

I saw one today on my orchids it worried me it looked weird i could tell it wasnt a bumble bee. Is it is just a fancy fly? Or does it make honey?

They are amazing honey bee mimics not only in appearance but also behavior.

In Santa Barbara I saw one this morning , drinking water out of our pond next to our honey bee hive . Wish I could post the pic of it here.

Here's my weird tale of the only time I've ever seen the Stripe-eyed Flower Fly: Last summer evening, after dark, I was at the check-out counter in the brightly lit American Apparel on Hollywood Blvd. , when I noticed the striped-eyed fly sitting on the glass counter. Of course the psychedelic eyes caught my attention. I got very excited and pointed it out to the woman ringing up my purchases. She was uninterested in this wayward insect. I had no idea what it was, but I talked the woman into finding me a cup so I could rescue it from retail hell. An easy catch, as it was quite lethargic. That evening I placed it on an Artemisia in my garden, and never saw it again. Now, thanks to you all at Bioscan, I have identified the cool fly at American Apparel!

Rescued one from our swimming pool in Pretoria, South Africa - early winter.

Sidney, I should have interviewed you for this blog post — if only I had known! Awesome story!

Solvang, Ca. Since recently creating a micro bird sanctuary with moving fresh water, and various steps leading to small bathing pools and eventually marshy places, I've had regular visits from European Honey and Cellophane bees gathering water to cool their hives. I've been offering them simple syrup in experimental dispensers and they freaking love it. Today I spotted a Flower Fly in the marshy area doing something similar. Perhaps the marshy lure can help your capture chances. Also I may be in a position to capture one if you've the need. P.S. (I made a moat in front of my door. Then I stocked it with bees. My neighbor said "Are you trying to tell me something?") ;)

Sidney, I love your stories! One very funny coworker once said to me that the striped eyed fly looks like it is wearing a pair of those crazy 80's sunglasses (that kind that look like window shutters), so maybe the fly was in the store trying to buy some shiny lamé scrunchies? Although we do not know for sure what kind of fashion choices the striped eyed fly prefers, I can safely say it was more at home in your garden than the American Apparel. Thanks for being an insect ally!

I took a picture of one on a tree where a branch recently broke off, in Fresno, CA.

Hi Sidney! Noting that "the larvae of the Stripe-Eyed Flower Flies are filth-dwelling Rat-Tailed Maggots," I would be very wary of the changing rooms at American Apparel!

Saw one this morning on our butterfly bush!

Just saw one of these on a potted succulent in Santa Monica - thought it was some strange bee. Thanks for your informative post for identifying it for me!

Saw one this morning on our butterfly bush. Santa Monica California

I saw one today and i tooke a photo of it. it have a tail i was so impressed because i didn't saw an insect like this before. Lebanon

I live in N.E. Santa Ana on the border of Orange in Orange County and found one of these dead in our pool. I have a pretty good pic of it as well if you would like to see it just let me know.

Photographed one at Fullerton Arboretum, California last weekend. Just posted on my Instagram. @naturebypaul

I saw quite a few hovering at the flowers of our mango tree, July 2017 - Barberton, South Africa. Thought it was a kind of bee. Thank you for the article.

Spotted one on a flower next to the Venice canals this morning! Glad this blog/article exists, now I know what it is.

These cover our backyard basically. They're everywhere, they've been around for a few months. - California (its September rn)

Just saw one in my backyard - thought it looked weird so I caught it in a jar and started searching. Now I know what it is.

Saw one in Cape Town, South Africa. Glad to finally know what it was. Thanks!

I photographed one in South Africa. I wish I could add the picture. It looks VERY similar to your pictures.

I just took some pictures of bees that I believe are this same species in Rosemead, Ca. Would love confirmation.

Years ago while working as a self employed Gardener, I had to remove a decaying barrel cactus from a home in Phoenix AZ. There was a group of fairly large "snorkel" tailed maggots in the cactus at that time. They were nearly an inch long. Surprisingly, they moved quite quickly in the liquid insides of the cactus which was nearly flat. I wonder if they are the same type of fly.

Just saw one in my yard in Norco, CA and googled strip eyed honeybee because that's just what it looks like. Great info!

Took some photo's of one in Berlin, East London, South Africa.

Many of these things invading my shops portacool in the desert of la county.

I just caught one of these flies and I dont know who I should give it to for research since this fly isn't common

I caught one

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