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Fantastic Fly Friday, the Anastrepha Fruit Fly

Posted on March 6, 2026 by "BUGGING" YOU FROM San Juan Island One comment

Today I have a beautiful Fruit Fly (Genus Anastrepha) to show you. I found this specimen when visiting Tulum, Quintana Roo, MX in late January. The place we stay in Tulum has a swimming pool virtually no one ever uses. I love this place so much because I almost always have the pool entirely to myself. Everyone else is at the beach!

However, this particular pool is not maintained so well. More often than not, the filtration system isn’t turned on. I spend the first 15 minutes or so walking around in the pool to skim off all the bugs with a cup I bring from our room.

Unfortunately, my efforts to communicate, in broken Spanish, a request for a pool skimmer to the maintenance workers was a total failure. Probably they secretly referred to me as loco el bicho señora, or something like that. My Spanish is terrible. If you know me well though, finding bugs in the pool is literally one of the reasons I love staying at this place. I have my own vacay niche! Surveying for entomological diversity found in the pool.

There were more than a few bugs for me to “save,” that had landed on the water surface. Some, like this fly, had unfortunately already expired. I skimmed them all out, photographed them, then uploaded my observations onto iNaturalist. I even resuscitated a few that I thought were dead. Toilet paper or tissue paper “beds” work pretty well for drying them out in a pinch.

I collected these photographs because I really appreciated the cool picture window patterns on the wings. This is one characteristic of fruit flies. This is also a female specimen as you can see from the longish posterior appendage, her oviscape. Last week, I tried to create a space away from social media to decompress, so I sketched her (to the best of my ability) and used my colored pencils to bring her to life. Probably I did not get all her bristles in the right places. On flies, bristles are diagnostically quite important. I’m not quite there with my artistic rendering, but it was a relaxing activity.

In spite of their unique and beautiful wing patterns, fruit flies are often considered agricultural pests. Probably they wouldn’t be a pest except that we have these giant industrialized agricultural operations to feed more people than the planet should ever support, and probably, we artificially enable populations of various pests to explode because we are creating extra habitat for them. Fortunately, some targeted biocontrol and Sterile Insect Technique (SIT) has been effective enough to move producers away from utilizing harmful and unsustainable methods of chemical control, although I imagine some operations continue to apply pesticides.

This particular fruit fly is in the Genus Anastrepha. I haven’t really attempted going beyond genus level to identify this one to species. Anastrepha ludens, however, is a name that pops up often in literature from studies in Mexico and California. Anastrepha is a genus in the Family Tephritidae and I believe there are over 200 species of Anastrepha fruit flies in the Americas.

If you are interested in reading more about this genus, I would start off sending you to the 1963 study by Foote and Blanc, referenced below. I am currently waiting on a text I ordered from Abe Books on fruit flies, and will be doing additional reading once it arrives.

One interesting taxonomic tip I can leave you with: Tephritidae are true fruit flies. Those small flies that get into the bananas on your counter or into your rotting compost that many folks refer to as fruit flies aren’t fruit flies at all. They are vinegar or pomace flies, a completely different family called Drosophilidae.

Find out more when you follow me on Fantastic Fly Fridays!

References and Further Reading

Arias OR, Fariña NL, Lopes GN, Uramoto K, Zucchi RA. 2014. Fruit flies of the genus Anastrepha (Diptera: Tephritidae) from some localities of Paraguay: new records, checklist, and illustrated key. J Insect Sci. 1;14:224. doi: 10.1093/jisesa/ieu086. PMID: 25525098; PMCID: PMC5634125.

Baker, A. C. (Arthur Challen). 1944. A Review of studies on the Mexican fruitfly and related Mexican species. Washington, D.C.: U.S. Dept. of Agriculture. https://babel.hathitrust.org/cgi/pt?id=uva.x030450595&seq=3

Bugguide.net. 2026. Anastrepha ludens. Bugguide.net. https://www.bugguide.net/node/view/71452

Greene C. T. 1934. . A revision of the genus Anastrepha based on a study of the wing and on the length of the ovipositor sheath. (Diptera: Tephritidae) . Proc. Entomol. Soc. Wash . 36 : 127 – 179 .

Foote, R. H. and F. L. Blanc. 1963. The Fruit Flies or Tephritidae of California. Bulletin of the California Insect Survey 7: 1-117, 118 figs., 104 maps, colored frontis

Norrbom A. L. 2004. . Anastrepha Schiner (Diptera: Tephritidae) . http://www.sel.barc.usda.gov/Diptera/tephriti/Anastrep/Anastrep.htm .

Stone A. 1942. . The fruit flies of the genus Anastrepha , pp. 112. United States Department of Agriculture, Miscellaneous Publication 439 .

Fantastic Fly Friday

Posted on February 27, 2026 by "BUGGING" YOU FROM San Juan Island Leave a comment

Here’s a unique specimen I have to show you. I found this fly on Wednesday after lunch when I went to look for a different species of fly around our above ground pool. I was actually looking for Woodpecker Flies when I found this one. Since I’ve committed to doing a presentation about them for the Scarab Society in September, I’m hoping to observe these weird Woodpecker flies again in the wild and take additional photos and videos to add to what I have collected already.

I didn’t expect to see anything IN the pool. Mostly, I was looking at vertical surfaces, like the sides of the pool and the sides of a nearby tree. When I glanced across the surface of the water, this little one stood out right away. I got a paper bowl to gently scoop it out, expecting it was deceased. It surprised me when it moved just a bit, then wiggled and flipped off the bowl onto the ground.

I bent down to inspect it, and when I touched it, it flipped around again like a fish out of water. Strange.

I had a plastic cup, so I managed to recapture the fly, wet and bedraggled as it was. I took it back into the house long enough for me to get my other camera. The lighting was better outside, so back out we went.

In case you are wondering, this is one of the Picture Wing Flies in the family Tephrididae. Also known as Fruit Flies. “Picture” references the patterned spots or stripes on the wings. There are other flies, like Drosophila sp., called fruit flies that aren’t actually fruit flies at all. THIS is a true fruit fly.

Many species of fruit flies are known for their pest status, however, there are over 4,300 described species in this family and the great majority of them are not pestiferous at all. They are merely a part of the local, natural ecosystem at large.

I used a key and geographic distribution records to determine the species for this one and believe it to be Chetostoma californicum. Trying to find host plant information led to me to do some deeper digging and to actually order a few more reference books on Tephridid flies. I have another fruit fly specimen I found when we were in Mexico, and plan to share that one with you next Friday. As I learn more about this particular one though, I will update my blog post accordingly.

The reference material I did find about Chetostoma californicum was largely from California and Arizona. Inferring from the documented host plant relationships recorded, it is likely one relationship possible in our immediate area is with native honeysuckle (Lonicera sp.). I also read adults of this species have been collected from Pines (Pinus sp.). We have a Pine tree just next to our above ground pool where the fly was collected.

Geographic distribution records for this fly include Western North America, primarily coastal, down to CA and into Arizona. You can view the GBIF map of reported sightings here – https://www.gbif.org/species/1623842 and also search for observations of the species posted on iNaturalist https://www.inaturalist.org/observations?subview=map&taxon_id=335747

Chetostoma californicum, identified by the oral edge of
bucca (cheek) with a row of about 10 coarse, black bristles with a few finer
black setae at the posterior end of the row. (LeBlanc, 1959)

The only additional personal record I have of this fly on San Juan Island is from February 16, 2024. I would conclude, based on my own observations, that this fly is not particularly an abundant species here. In checking for reports of the species on San Juan, my two posted observations are two of three total for the county.

Now if I can just find out what’s behind the fish flippy behavior…..stay tuned!

Chetostoma californicum (with pollen stuck to it after I accidentally dropped it into a Crocus flower)

Thanks for reading.

References

No author. 2026. Chetostoma californicum. Grokipedia. https://grokipedia.com/page/chetostoma_californicum

Cole, F. 1969. The Flies of Western North America. University of California Press. Berkeley and Los Angeles.

Foote, R.H. and Blanc. F.L. 1963. The Fruit Flies or Tephritidae of California. Bulletin of the California Insect Survey. University of California Press. Berkeley and Los Angeles. https://essig.berkeley.edu/documents/cis/cis07.pdf

LeBlanc, 1959. A new species of Chaetostoma from California (Diptera: Tephritidae). Pan-Pacific Entomologist. 35:201-204. https://biostor.org/reference/225819

Wasbauer MS. 1972. An annotated host catalog of the fruit flies of America north of
Mexico (Diptera: Tephritidae). Occas. Pap. Calif. Dep. Agric. Bur. Entomol. 19:1–172.

Identifying the Nicocles canadensis Robber Fly

Posted on June 17, 2025 by "BUGGING" YOU FROM San Juan Island Leave a comment

It has taken a bit of time to finally sort out genus and species for this very cool Robber fly with beautiful caramel-brown mottled wings I spied the evening of June 6, 2025. It perched on a dried apple mint stem from last season, no doubt scouting the terrain to see what might be on the menu for dinner. Robber flies (Family Asilidae) are predatory. They catch other small invertebrates to eat, paralyzing them with special salivary digestive enzymes and then sucking up the liquified contents through the proboscis (Cannings, 2013).

Getting to an identification beyond Genus for this one has been incredibly frustrating, and complicating the process is the limitation of the key I was using (Wilcox, 1946), which primarily describes male specimens.

Robert Cannings has studied the Asilidae for many years in British Columbia and states this genus “sorely requires systematic attention.” I finally just gave up and reached out to Rob for help. He wrote me and said, “I’m pretty sure this is Nicocles canadensis. It’s a female, and some females are difficult, even when under a scope, because the Wilcox key, which is the best we have for now, deals with them poorly and concentrates on males. Nicocles canadensis is the species in the genus most often seen on BC’s south coast and, I assume, in your area.”

This is the only Nicocles fly I’ve ever found on our property on San Juan. According to Rob’s 2014 publication (linked in the references below) in Canada, ” Nicocles canadensis is restricted to Garry oak savanna and adjacent dry woodland on southern Vancouver Island (Saanich is the type locality),” so I anticipate this may be similar for our neighboring area.

Check out the attached references if you are interested in learning more about Robber Flies in our region.

Thanks for reading!

References

Cannings, R.A. 2014. The Robber Flies (Diptera: Asilidae) of Western Canadian Grasslands. 10.3752/9780968932179.ch7. https://www.researchgate.net/publication/268524943_The_Robber_Flies_Diptera_Asilidae_of_Western_Canadian_Grasslands

Cannings, R.A. 2013. Robber Flies (INSECTA: DIPTERA: ASILIDAE) Of The Montane Cordillera Ecozone.

Cannings, R.A. 1994. Robber Flies (Diptera: Asilidae) new to Canada, British Columbia, Yukon,
and the Northwest Territories with notes on distribution and habitat. J. Entomol. Soc.
British Columbia: 91: 19-26. https://www.biodiversitylibrary.org/part/213777

Cole, F. R. 1969. The Flies of Western North America. University of California Press. Berkeley and Los Angeles.

Fisher, E.M., and Wilcox, J. 1997. Catalogue of the robber flies (Diptera: Asilidae) of the
Nearctic Region. Unpublished preliminary draft.https://staff.royalbcmuseum.bc.ca/wp-content/uploads/2013/08/Catalog-Nearctic-Fisher-Wilcox-1997-manuscript-copy.pdf

Geller-Grimm, F. 2008. Robber Flies (Asilidae). Internet site at http://www.geller-grimm.de/asilidae.htm

Melander, A.L. (1924) Studies in Asilidae (Diptera). Psyche [1923] 30: 207-19. https://onlinelibrary.wiley.com/doi/pdf/10.1155/1923/83461

Wilcox, J. 1946. New Nicocles with a key to the species (Diptera, Asilidae). Bulletin of the Brooklyn Entomological Society 40 (1945): 161-165; New York – Lancaster. https://www.biodiversitylibrary.org/page/50573094#page/180/mode/1up

Fantastic Fly Friday

Posted on April 11, 2025 by "BUGGING" YOU FROM San Juan Island Leave a comment

I thought I’d write up a short post about all the wonderful flies (and a few others) pollinating our plum trees in this cool spring weather. Why feature the flies? Well, for starters, the plum tree blossoms are white and flies love the color white. Another reason to feature the flies is because they are under-recognized and under appreciated, but very important pollinators. Some fly larvae even serve as pest predators, eating aphids. Others, like the tachinid fly below, use caterpillars that defoliate trees as hosts for their larvae to develop. Flies are also awesome because they do not sting! Some even “dance!” My favorite fly hasn’t shown up yet. It’s a Conopid Fly. More about that one later though…

Tachinid Fly (Epalpus signifier)

This past week in the media, there have been so many posts about the decline in honey bees. While there are some (unwanted) honey bees showing up on days when the temperatures climb above 50 degrees, honey bees aren’t active if it is cooler. Flies, on the other hand, are quite busy at work pollinating and do just fine when it might only be 40 outside. Flies are awesome! They need our support and appreciation.

I’d like to add (and I do know something about this because of my entomology background), that honey bees are just not necessary on San Juan Island. In fact, they might even be a very bad thing. They showed up at our plum tree as the temperature warmed up the other day, and as they arrived in increasing numbers, they kicked off ALL of the native pollinators that I had been observing. 😦

For honey bees to fly out of the hive and forage, they need temperatures above 50 degrees. In my experience keeping bees (as part of my graduate school work), they typically do not survive well on the island unless they are fed supplemental sugar water. Think about the ecological footprint of growing sugar to feed the bees!

Feeding honey bees attracts (and supports) the buildup of yellow jacket populations which are attracted to honey bee hive resources (including eating the honey bee brood developing in the hive), and honey bees also bring pests and pathogens that impact native bees (especially bumble bees). One more thing! If you are growing tomatoes, bumble bees are your pollinators, not honey bees.

I hope you will read and consider this recent study published about how honey bees were negatively impacting native pollinators on Giannutri Island in Italy. They were causing a decline in the populations of wild bees. In fact, the study cited an “alarming 80% decline in wild bee abundance over 4 years” (Pasquali et al. 2025). You can access this study to read it yourself here: https://www.cell.com/current-biology/pdfExtended/S0960-9822(25)00262-3

Enjoy the gallery of the native pollinators that I was fortunate to photograph and be able to share. Be a fly fan! Be a native bee fan! Learn about our unseen, but important night time pollinators (moths), and PLEASE LEAVE THE HONEY PIGS for the mainland industrial farm operations.

Golden Dung Fly (*Scathophaga stercoraria*)

(*Melanostoma mellinum* )Variable Duskyface Fly

Sericomyia chalcopyga Western Pond Fly

Bibionid Fly (Bibio sp.) and Hybotidae Dance Fly (Bicellaria sp.)

(Melanostoma mellinum) Variable Duskyface Fly

References

Anderson, H. L. D. (2024). Nocturnal moth communities and potential pollinators of berry agroecosystems in British Columbia (T). University of British Columbia. Retrieved from https://open.library.ubc.ca/collections/ubctheses/24/items/1.0447737

KEARNS, C. A. 2001. North American dipteran pollinators: assessing their value and conservation status. Conservation Ecology 5(1): 5. [online] URL: http://www.consecol.org/vol5/iss1/art5/

Pasquali, Lorenzo & Bruschini, Claudia & Benetello, Fulvia & Bonifacino, Marco & Giannini, Francesca & Monterastelli, Elisa & Penco, Marco & Salvati, Vania & Simbula, Giulia & Skowron Volponi, Marta & Smargiassi, Stefania & van Tongeren, Elia & Vicari, Giorgio & Cini, Alessandro & Dapporto, Leonardo. (2025). Island-Wide Removal of Honey Bees Reveals Exploitative Trophic Competition with Strongly Declining Wild Bee Populations. 10.2139/ssrn.5081459. https://www.sciencedirect.com/science/article/pii/S0960982225002623#:~:text=Article-,Island%2Dwide%20removal%20of%20honeybees%20reveals%20exploitative%20trophic%20competition,strongly%20declining%20wild%20bee%20populations

Ssymank, A., Kearns, Bonn & Carol. Flies – Pollinators on two wings. The Diptera Site. https://diptera.myspecies.info/diptera/content/flies-–pollinators-two-wings

Diptera

April 5, 2025 – Herman finds a fly

Posted on April 5, 2025 by "BUGGING" YOU FROM San Juan Island Leave a comment

That’s right! Herman the Persian found something interesting in the yard when we were outside sunning ourselves a bit this afternoon. He found one of the Bibionid March flies (a female). If you read my post yesterday https://buggingyoufromsanjuanisland.com/2025/04/04/nuptial-gifts/, you might note that Bibionid flies were being hunted by Empis flies who rolled them into little balls as nuptial gifts used to woo the lady Empids to mate.

Female Bibionid fly digging chamber to lay her eggs.

Evidently, a few of these Bibionid flies escaped that destiny and actually mated with their own kind. THIS one, that Herman found, was hard at work digging her own death chamber where she would expire soon after laying her eggs. Incidentally, the adults are very short-lived, and in fact, live only about 5-7 days with the primary objective of mating, and for the adult female to lay her fertilized eggs. In spite of their brief existence, adults are also thought to be important early pollinators of orchard trees. Yes, you heard me right! Flies don’t get nearly as much credit for pollinating as they deserve to receive.

I watched her digging with her fossorial forelegs. It seemed to be an impossible task, but she made slow and steady progress. She was still hard at work before we went back into the house about half an hour later. I marked the spot with a rock so I could go back and check, but I suspect even with the rock nearby as a marker, it will be next to impossible to detect any disturbance in the soil tomorrow. We’re supposed to get rain this evening.

In approximately 30-35 days, the eggs she lays will hatch underground. The larvae will live in the top layer of soil and feed gregariously on leaf and needle litter, decaying organic matter, and sometimes on below-ground parts of plants.

If you’re curious, you can read more about Bibionid flies in the attached links. I did see some additional Empis fly males dancing about today with their Bibionid “balloons” or nuptial gift balls for prospective mates.

Thanks for reading. 🙂

References

Bugguide.net. 2025. Family Bibionidae – March flies. https://bugguide.net/node/view/3834

Morris, H. No date. The larval and pupal stages of the Bibionidae. Entomological Department, Institute of Plant Pathology, Rothamsted Experimental Station, Harpenden. https://core.ac.uk/download/pdf/212009582.pdf

A Sedgesitter

Posted on March 13, 2025 by "BUGGING" YOU FROM San Juan Island Leave a comment

This was Wednesday’s bug of the day. I’m a day behind writing up my post. Although I have tried to get out for a quick bug search every day, it’s been overcast and/or drizzly here this past week. I was excited to see this little fly hunkered down on a twig of our fruitless cherry tree, the tree that I whacked off as an unwanted upstart for several years before I discovered how interesting it is.

Western Forest Sedgesitter, (*Platycheirus trichopus*), I believe

That tree is a mini ecosystem: floral nectaries that feed the aphids, aphids, slave making ants that have fights to the death (winning) with the carpenter ants that try to invade our home every spring, and the birds that rip the leaves apart trying to get the aphids. Now I can add Syrphid flies to the list!

That’s what this is. A syrphid fly. Syrphid flies eat aphids. It would make perfect sense for this adult to lay eggs on the tree, though I’m not sure what would happen because the ants that farm those aphids are certainly willing to die defending them. I could definitely see the ants overtaking the syrphid fly larvae. Nevertheless, the fly flew off. Somewhere.

I believe this particular fly is the Syrphid fly species Platycheirus trichopus, the Western Forest Sedgesitter. While difficult to ID to species, I did reference the helpful ID guide by fly expert, Even Dankowicz. https://docs.google.com/presentation/d/19F1qRGpmNDgaGE13M2SMUBlI846JicTOYjIescjVTHw/preview?slide=id.g8918834f0e_0_92

This species, as mentioned earlier is pretty small at only about 6.8-9.4 mm. Geographic distribution ranges from the Rocky Mountains west from Alaska to Mexico (bugguide.net). Adults of this genus are known to feed on the pollen of wind pollinated plants like Willow (Salix sp.) and various grasses (Poaceae), and sedges (Cyperaceae). It is believed they are better adapted to activity in cooler temperatures and that fits with yesterday’s rather gloomy spring day.

Thanks for reading!

References:

Dankowicz, Even (2023). “Common Pipizini, Paragini, and Bacchini Species of the Southwestern U.S. (CA NV AZ UT NM CO)”. The Fly Guide: Field/Photo ID for Flies. pp. 9–10.

Bugguide.net. 2025. Syrphidae. https://bugguide.net/node/view/196

Bubbles

Posted on July 12, 2024 by "BUGGING" YOU FROM San Juan Island Leave a comment

Well, this little fly got my attention yesterday. We had a contest. The fly bet it could outlast my grip on my phone as I took video of the bubble blowing. We called a tie somewhere around the 4 minute mark when my hand was shaking and I was about to drop my phone. The fly, quite satisfied with its performance, waltzed about on the mint leaf and posed for a few still photos, after I got the blood flowing into my hand again.

This is a Black Blow Fly (Phormia regina) in the family Calliphoridae. These flies are found ranging throughout North America, Eurasia, and Hawaii. They are a species of importance in the science of Forensics. Blow flies are attracted to dung and carrion, and when found on a corpse, they can be used to estimate time of death. The larvae or maggots of sterile blow flies are also used in the cleaning of wounds, removing decaying flesh and secreting antimicrobial peptides as they feed (Díaz-Roa et. al. 2018). Occasionally, they can contribute to secondary myiasis “fly-strike” of wounds in livestock, wildlife, and pets.

Phormia regina Fly – San Juan Island, WA 07.11.2024

Why is the fly blowing bubbles? It’s not black bubblegum. I’m not sure why the bubbles were black in color. Perhaps something to do with what the fly had been eating. The fly is blowing bubbles to cool down and it’s actually called BUBBLING. Take a look at Ray Cannon’s Nature Notes and you’ll learn it’s part of an evaporative process where the fly moves a droplet of fluid in and out and of their buccopharyngeal cavity over and again before eventually swallowing it (Gomes et al., 2018, Cannon, R. 2020).

Flies aren’t the only group that practices bubbling. Various species of Hymenoptera also use this method to cool themselves and also to evaporate the excess water from the food (nectar) they’ve consumed (Portman et. al. 2021).

Thanks for stopping by!

References and Further Reading

Cannon, Ray. 2020. Flies Blowing Bubbles. Ray Cannon’s Nature Notes. https://rcannon992.com/2020/09/07/flies-blowing-bubbles/

Díaz-Roa A, Patarroyo MA, Bello FJ, Da Silva PI Jr. 2018. Sarconesin: Sarconesiopsis magellanica Blowfly Larval Excretions and Secretions With Antibacterial Properties. Front Microbiol. Sep 28;9:2249. doi: 10.3389/fmicb.2018.02249. PMID: 30323791; PMCID: PMC6172317. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6172317/

Gomes, G., Köberle, R., Von Zuben, C. J., & Andrade, D. V. 2018. Droplet bubbling evaporatively cools a blowfly. Scientific reports, 8 (1), 1-7.

Murray, T. 2023. Species Phormia regina – Black Blow Fly. Bugguide. https://bugguide.net/node/view/53678

Portman, Z., Ascher, J. & Cariveau, D. 2021. Nectar concentrating behavior by bees (Hymenoptera: Anthophila). Apidologie 52, 1169–1194. https://link.springer.com/article/10.1007/s13592-021-00895-1

Know Your Pest Predators – Make Friends with Eudioctria sackeni

Posted on July 11, 2024 by "BUGGING" YOU FROM San Juan Island One comment

This is one of my favorite garden residents (Eudioctria sackeni), or the Sacken Longhorn Robber. I remember the first time I saw one of these, I thought, “Wow, it’s an Ombre Fly!” If you didn’t know, “ombre” means the blending of one particular color hue to another, often from light tints to dark. The coloration in this particular fly is distinctly “ombre,” though it varies in individuals within the species.

Eudioctria flies are in the family group, Asilidae or Robber flies. They are voracious predators of small insects that can be pests of gardens and orchards. Here, you see this one enjoying a small dipteran (fly) of some variety, perched on the leaf of one of my mint plants. The mint is a popular scouting platform. On any given day in the summer, I’ll see 4 or 5 of these flies in a six foot strip of mint which has become quite abundant in the yard over the past few years. The mint seems to be quite attractive to pollinators, and it also provides shelter for other bugs and critters. Our little tree frogs love to sit in the mint too.

Reference and further reading

Species Eudioctria sackeni – Sacken Longhorn Robber. BugGuide. https://bugguide.net/node/view/60617

What’s Biting Me? Episode ONE, San Juan Sniper

Posted on July 6, 2024 by "BUGGING" YOU FROM San Juan Island One comment

I’m going to start a new bug series called “What’s Biting Me?”

I’m starting this series because I have such bad reactions to bug bites in general, and I’m exasperated when people blame mosquitoes and spiders for everything. Also, if you’re one of those who is tired of it getting crowded here in the San Juans, feel free to share this with anyone who is thinking about moving here – or with anyone you WISH would move off the island. Maybe they’ll decide to live somewhere else. 😉

Epidode ONE, the San Juan Sniper

This is one of the Rocky Mountain Bite Flies (Symphoromyia sp.). It’s a Snipe fly in the family Family Rhagionidae, and it bit my husband today. Those are NOT my hairy legs. They’re my husband’s.

After getting some pictures, I went inside to look up what information I could find about the Genus and narrow down what species are in WA state. In doing so, I came across this interesting, and disturbing medical case report of a woman who had a severe allergic reaction to the bites of these flies. Now this was in the 70’s, in Forks, WA, but if this fly had bitten ME instead of my husband, it’s very likely I’d be the next case write up.

Attaching the paper in the link here if you care to read it. The woman could have D-I-E-D from anaphylactic shock.

You’ve been warned.

No worries, just stay indoors and you’ll avoid being bitten by the San Juan Sniper.

Symphoromyia Genus

Size: 4.7-9mm

Food: Females of some species of this genus are blood feeders. Symphoromyia females are common biting pests in the west. Males do not take blood meals. Both adults and larvae will prey on small insects.

Habitat: Adults are commonly found in woods near moist places, often found on foliage or grass, positioned with head resting head downward. Larvae occur in moist meadow soil, moss, decaying wood (incl. galleries of wood-boring insects), under bark, occasionally in water (bug guide.net).

References and Further Reading

Aldrich, J. M. 1905. A Catalogue of North American Diptera. Smithsonian Miscellaneous Collections 46:680.

Bowser, Matt. 2017. Refuge Notebook: The bad biter par excellence. Peninsula Clarion. https://www.peninsulaclarion.com/life/refuge-notebook-the-bad-biter-par-excellence/#:~:text=Very%20little%20research%20has%20been,not%20known%20to%20transmit%20disease.

Bugguide.net. Family Rhagionidae (Snipe Flies). https://bugguide.net/node/view/116

Kerr, Peter H. 2004. REVISION OF THE GENERA OF THE RHAGIONIDAE OF THE WORLD (DIPTERA: BRACHYCERA). Doctor of Philosophy Dissertation. University of Maryland, College Park. https://drum.lib.umd.edu/items/7f964daf-76bd-467e-ac36-18a523ac5e5a

Turner WJ. A case of severe human allergic reaction to bites of Symphoromyia (Diptera: Rhagionidae). J Med Entomol. 1979 Feb 8;15(2):138-9. doi: 10.1093/jmedent/15.2.138. PMID: 448692 https://www.tesble.com/10.1093/jmedent/15.2.138

Mitten feet

Posted on June 23, 2024 by "BUGGING" YOU FROM San Juan Island Leave a comment

This is one of my “Know your pest predators” posts, featuring one of our PNW flies. Flies are all too often maligned and under-appreciated. We think of flies as spreading disease and being a nuisance, yet many of them perform incredibly important jobs as pollinators and pest predators. Yesterday I was sleuthing flies in the yard and found these metallic green beauties. Here is a Dolichopus (“doe-LICK-uh-pus”) male and female. The “dolicho-“ part means “long”, and the “-pus/-pod” part means “leg” or “foot.”

Some species of Dolichopus males (like this one) have little “flags ” or “mitten” front feet they wave or flap around to woo the ladies. Reading about this very large group of flies has been interesting and you can learn more about their courtship behaviors in Van DuZee et al. (1921).

These flies are predators of small, soft-bodied invertebrates as adults and during their larval stage. You can thank them for helping keep populations of aphids under control in your garden.

You’ll find these flies in northern latitudes in North America. “Dolichopus species are among the largest and most common members of the family Dolichopodidae in North America. The majority of Dolichopus species prefer humid habitats and some are restricted to saltmarshes,” (Pollet et al. 2004).

References:

MARC A.A. POLLET, SCOTT E. BROOKS, JEFFREY M. CUMMING. 2004. “CATALOG OF THE DOLICHOPODIDAE (DIPTERA) OF AMERICA NORTH OF MEXICO,” Bulletin of the American Museum of Natural History, 283, 1-114,

Van Duzee, M. C., Cole, Fr R., and Aldrich, John Merton. 1921. “The dipterous genus Dolichopus Latreille in North America.” Bulletin of the United States National Museum. i–vi, 1-304, 16 pls. https://doi.org/10.5479/si.03629236.116.i

Key to male nearctic Dolichopus species here – https://digitallibrary.amnh.org/items/5c3c75c8-27ae-47e6-acac-59ec0c30d1cb/full