Identifier Profile: Fly Identifiers

It’s been a while since the last Identifier Profile (sorry about that!), so I thought I’d feature the top five identifiers of syrphid flies (commonly known as hover flies or flower flies, among other names) in North America this month and put together a sort of “oral history” of how they’ve built both resources and a community of identifiers for this taxa and region. I think it’s a great model that could work for other places and taxa around the world.

These identifiers are:

@trinaroberts - Trina Roberts

@edanko - Even Dankowicz 

@zdanko - Zachary Dankowicz 

@catherine_g - Catherine C. Galley 

@upupa-epops - Caleb Scholtens

Collectively, as of February 21st, 2023, they’ve added nearly 300,000 IDs to syrphid observations in North America. 

I’ve tried to make things roughly chronological here, but with an eye on giving it a narrative flow. Some quotes have been lightly edited for clarity. The “Fly Guide” referred to multiple times can be found here.


Even: In high school, I started photographing insects and identifying them with BugGuide. Almost every day I'd find new creatures I'd never seen before.

I first joined iNaturalist for feedback on plants, mollusks, and other groups not covered by BugGuide. I realized that iNaturalist relies on everyone to help, and quickly got started identifying isopods, millipedes, and other groups where a lot of observations were unidentified. In mid-2017, I started going through all the unidentified true flies of “Tropical Asia” (India to Vietnam and New Guinea) in the hopes of finding photos of Cacatuopyga flies (large, striking wasp-mimics only known from a handful of museum specimens). This eventually developed into my current fly specialty.

Caleb: I found out about iNaturalist from a blog post by @mikeburrell in spring 2017, I would've been in my second-last year of high school then. I was already hooked on eBird for keeping track of the birds I'd observed and had been craving something similar for other wildlife, so as soon as I figured out iNat I started uploading old photos of bugs, plants, herps etc. I had always been curious about bugs but had no idea how to learn about them, so posting photos and quickly having people put names to them was magical. 

Wanting to give back (and bored and procrastinating from schoolwork...) I started dabbling with identifying. I had the most experience with birds, but I found that helping with them wasn't very productive because there were so many other people identifying them already. After trying a couple other groups I settled on hover flies because they were relatively easy to identify, and at the time they weren't getting much attention from anyone else.

Even: Flower flies (Syrphidae) are a group of charismatic pollinators that can be fun to identify. Starting in mid-2018, I found it useful to organize checklists and tables of diagnostic characters for different species. Martin Hauser (@phycus), Bill Dean (@billdean), and several others set the stage with their notes on BugGuide. I shared my “notes” with the iNat community, but only a handful of highly-motivated people used them. My “note documents” were too dense to be quickly consulted, even for me!

Caleb: My focus with hover flies has been particularly on Calligraphers (Toxomerus), which are appealing to me because they're abundant and their abdomen patterns are really beautiful, plus they have a cool common name. Those things do apply to a lot of other syrphids though!

Once I had (temporarily) identified all the Toxomerus in Canada and the US, I started observing and identifying other hover flies, particularly Allograpta and other Syrphini, mainly using BugGuide comments as a resource. The new field guide for syrphids of northeastern North America came out a bit later and was helpful as well.

At some point I realized that writing out how to identify them in a journal post would have the double benefit of consolidating what I've learned so I can reference it when I forget something, and teaching other people if they're interested in helping (or just curious about their own observations).

Even: Caleb Scholtens (@upupa-epops) had some experience with Globetails (Sphaerophoria), Aphideaters (Eupeodes), and some other hard syrphid groups with a lot of similar species. I messaged him and he was enthusiastic about working together on guides to these types of flower flies.

I hoped that putting together a “field guide” of sorts could help people and encourage budding identifiers. Caleb and I started by making a “field guide” to common species of the tribe Syrphini in the southwestern USA. The guide was a big hit, and is now linked along with many other recent guides at https://sites.google.com/view/flyguide/species-guides/syrphidae.

Trina: I am a biologist (mammalogist and biogeographer) by training, and I work at the Natural History Museum of L.A. County, but that’s more because I’m a naturalist at heart than the other way around. As of 2019 I had started to use and enjoy iNat frequently as an observer, and I had done some very general IDing for the museum during the City Nature Challenge.

I was posting observations and other people were IDing them, but I wasn’t returning the favor, and I felt it was time I started contributing more to do my share.  So, over the winter I had decided some more IDing would be a good way to do two things at the same time: learn some California taxa, and do my part for the iNat system. My original goal was to ID ten times my number of observations and then decide whether I wanted to keep going.

Catherine: Even’s idea of creating The Fly Guide as an online document specifically designed to help identify live specimens in photographs has been especially helpful. I learned about it in September 2020 and started using it immediately to identify my observations. It is a wonderful resource but for the neophyte I was, there were so many characteristics and subtle nuances between species that at first I could not even notice some of the differences. Using the visual keys was a challenge but I was learning and as I became more familiar with the features I had to look for, I started taking more identifiable photos. I never imagined that I was just at the beginning of an amazing adventure.

Trina: When the pandemic hit and I found myself suddenly spending a lot more time than usual in my apartment, it seemed like a perfect time to pick up the IDing idea.  After some false starts I decided I needed to pick a group to focus on. It had to be something with some interesting diversity, preferably found in my little urban backyard, fun to look at, with enough field marks that a non-specialist could start contributing pretty fast, and with enough of a backlog that identifiers were needed.  And I quickly realized that it also needed to have some active identifiers who didn’t mind being tagged and asked questions, because being able to get some feedback is crucial to learning.  Syrphidae was perfect!  There were a lot of un-IDed and half-IDed observations that included common and distinctive species, and thanks to the existing regular IDers there were friendly and responsive people who would confirm, correct, discuss, and appreciate as needed.

[It became apparent early on] that there are not very many good, thorough, identification resources for photos. When Even launched the first Fly Guide mini-guides that really sped up my learning process for common species that I hadn’t figured out yet, and I still point other observers toward those frequently.

Even: After Caleb and I shared our first flower fly guides, Trina Roberts (@trinaroberts) began making a large number of IDs on west coast syrphid observations. Trina has taught us a lot in the discussions on observations, and she is now the top identifier for Syrphidae with >130,000 identifications.

Zachary: I’m a junior in high school in Bethesda, Maryland. In December of 2020 - winter break of my freshman year - I was incredibly bored and had nothing better to do than to play video games and read books. My brother Even, who was home because of the pandemic, offered to help me find something to do, and at 12:51 p.m. on December 23, 2020, I made my first real identification on iNaturalist, of a Palpada pusilla (Syrphidae) in Florida. 

I continued identifying the Palpada on iNaturalist and built up basic expertise of the Nearctic species. A few weeks later, Even suggested that I could work on creating an illustrated dichotomous key to the species of Palpada in the USA and Canada, and I agreed enthusiastically. We finished the key a few months later and Even posted it on the Fly Guide, where it is now available. Over the next year, Even and I worked together to create illustrated keys for all of the genera of the tribe Eristalini in the Nearctic region.

Caleb: I am really impressed with how much they've covered already and how regularly they make progress on covering new taxa. I helped with the Syrphini guide but most of the work Even did with hover flies was as I was getting busier with university and I couldn't contribute as much as I would've liked to.

Catherine: Aware that the number of observations grew exponentially, Even would mention The Fly Guide and suggest that I become an identifier. It was nice of him but I made sure to let him know that I could not do it because I had no credentials and identifying was scary. I enjoyed iNaturalist and I did not want to fill it with errors, despite Even and later Zachary reiterating that making mistakes is the way to learn.

Zachary: In July of 2021, we thought it might be nice to get some more people interested in syrphids through what Even calls “identifying parties” on Zoom. I decided to ask on the iNaturalist Forum to see if anyone would be interested. And boy, were they!

Catherine: I attended the first class, which took place at the end of August and soon it became a series of weekly sessions that have made a huge difference in helping me learn more and gain confidence. Zachary created excellent videos and the informal meetings have been conducive to ask questions and practice identifying in a fun way.

Trina: I was happy to be able to help review some of the Fly Guide keys, but I haven’t found the time (yet) to contribute any of my own. I have tried to do what I can to support the sense of community, because it is definitely part of what keeps me coming back and I hope I can help make this welcoming and fun for others. The collaboration among identifiers is a big reason why this works; we can fix each other’s mistakes and consult on the tricky cases, and we all learn more in the process.

Catherine: Little by little I started expanding the number of species I could identify and Trina has always been willing to help and explain her reasoning. I try to identify syrphid flies regularly and although I am still making mistakes I know more than I did,  I am still learning, and I am incredibly grateful to Even, Zachary, and Trina for sharing their passion and empowering people like me.

Zachary: After that success, we met, and continue to meet, almost weekly and have developed a regular gang, notably including Catherine Galley, whose studious efforts, stemming from the meetings, have landed her a top 10 spot for global syrphid identifiers.

Caleb: Thankfully several syrphid researchers are active on iNat now (possibly because of me emailing them with questions multiple times?), which is super helpful for making progress outside of North America where there are even fewer resources to go off of (@gilfelipe, @phycus, and @ximo_mengual have been quite helpful). It gets tougher there especially because there are so many undescribed species, and even described species often don't have documentation that's helpful for photo identification.

Even: There are many ways for people to learn more and give back to the community by making identifications. Making IDs just by looking for a basic photo match is a bad idea with flies, but the guides we’ve put together should help if used carefully. The best way to learn quickly is to try and ID a lot of observations, and hold back and ask a lot of questions whenever you aren’t sure! We’re always happy to see new people making IDs.

Catherine: In December 2021, Mike Quinn (@entomike), a coleopterist at the University of Texas at Austin, sent me an invitation to the open house organized by the Texas A&M University Insect Collection. I knew that collections existed but I could not think of what I could do there. I contacted a friend, Scott Longing (@scottlonging) who is professor of entomology at Texas Tech University and asked him if it would make sense for me to go there. Scott suggested that I visit the TTU Invertebrate collections and he put me in touch with Jennifer Giron (@jcgiron) the acting curator.

At the beginning of January 2022, Jennifer gave me a tour, showed me some of the syrphid flies, and let me observe one under the microscope. I was amazed that I could recognize that specimen. She invited me to volunteer, which I accepted. She trained me and one year later I am finishing digitizing and identifying most of the syrphid collection. Furthermore during this year Mike has been instrumental in teaching me how to use the collection in relation to my iNaturalist observations.

Trina: I had no intention of becoming a top identifier in anything, but it turned out to be a lot of fun and I didn’t want to stop when I’d reached my original goal. Each observation is a little puzzle to solve, and there’s always something new to learn.

Caleb: I finished my undergraduate this past spring and am working in environmental consulting now; with all of that I've had less time for identifying recently so it's great to see a lot more people identifying hover flies now! It's crazy how much more accessible knowledge and expertise about nature is now; for example I see young birders picking up skills and knowledge much faster than I could have because of all the resources and more experienced birders they have easy access to online. If you're inspired to create your own guides, don't feel pressure to make them super fancy or cover a ton of species or regions. If you feel like there should be a better ID resource for a group of 3 underrated species in your state, make it! And don't be afraid to ask people with more expertise for questions or review; they're usually happy to share knowledge about the species they're passionate about.

(Top photo: Oblique-banded Pond Fly (Sericomyia chrysotoxoides) by @hill_jasonm (CC-BY-NC). Photos of identifiers from top to bottom: Even Dankowicz, Caleb Scholtens, Catherine C. Galley, Zachary Dankowicz, and Trina Roberts.)


In order to keep this blog post manageable I did only cover the top five syrphid identifiers for North America, but they mentioned that the iNat community at large, as well as the help of experts, were vital to building the resources and community described above. I want to share one last thing from Trina, which I think is really important.

…In a group with this many observations, everyone’s contributions help us keep (sort of) on top of the pile of IDs. As well as giving credit where it’s due, it’s important that people know you don’t have to do tens of thousands of IDs to have it make a difference, and I sometimes worry that the focus on top identifiers and leaderboards can convey that impression! If you look at syrphids broken into subfamilies or genera, or locally within individual states, you’ll see lots of other names on the ID leaderboards, and their effort is critical. @matthewvosper catching up on the backlog for Eristalis and Syrphus (and making the Syrphus key); @coolcrittersyt and others who stay on top of observations for a particular state or region; @jane41 and @spencerchau sorting various taxa; @johnklymko, @phycus, @kevinmoran, @billdean and others being willing to discuss the tricky or less common ones; all the people sorting Diptera and Pterygota and Insects into families to begin with… there are really quite a lot of people involved in one way or another.


- you can check out past meeting invites on the Flies of the US and Canada project’s journal page.

- and/or join the fly identification group email list here.

Posted on February 21, 2023 10:24 PM by tiwane tiwane

Comments

Are there groups doing similar things for other taxa and regions on iNat?

Posted by tiwane about 1 year ago

Thank you for the feature, Tony!

Posted by zdanko about 1 year ago

Amazing! A few of us Isopoda idintifiers are trying to do some similar things and this group has been an inspiration for us; thank you!

Posted by americanisopodolo... about 1 year ago

Thanks for covering this group. The shared expertise is greatly appreciated.

Posted by neylon about 1 year ago

Awesome! (Note: the link to Caleb's profile goes to upupa_epops rather than upupa-epops with a hyphen)

Posted by gatorhawk about 1 year ago

@tiwane you could probably do a similar group tribute for ant identifiers (Arman, Mett, etc) and bee identifiers (John, Joel, Jess, Trevor, Brian, etc)

Huge thanks to the hoverfly gang for all their time and free resources

Posted by egordon88 about 1 year ago

Nice. We are hoping to renew interest in flies as pollinators via the DipoDip project for southern Africa. https://www.inaturalist.org/projects/flies-diptera-of-southern-africa/journal/74556-dipodip
Whereas we are anticipating European dipterists assistance with identifications - they after all initiated the project, no doubt it will be a global effort.
Great to see how communities develop!

Posted by tonyrebelo about 1 year ago

@gatorhawk sorry about that, it's fixed now.

Posted by tiwane about 1 year ago

Thanks for posting. I've always appreciated the help of these identifiers!

Posted by robinellison about 1 year ago

On first attempting to ID hoverflies on another continent I was unsure what to expect - would I be treading on someone's toes? Not a bit of it. It was remarkable to discover straight away this welcoming team, immediately ready to share knowledge and bounce ideas around. Great work, great team! Thanks to you all.

Posted by matthewvosper about 1 year ago

I like the way @tiwane is trolling us by using a thumbnail photo from an observation that remains largely unidentified despite a lot of head-scratching (not the lovely Sericomyia on this page, but the thumbnail I see on the homepage that links to this post).

It's been so fun working with all of you on this and I really am grateful for this community of friendly and nature-minded people.

Posted by trinaroberts about 1 year ago

@trinaroberts Sorry about that! I just used one of my own photos that would read OK at small size so I didn't have to deal with putting attribution anywhere.

I've also added Trina's photo the piece, thanks for sending it over, Trina!

Posted by tiwane about 1 year ago

I'm kidding! Also not sure what it says about my identification obsession that I recognized it.

Posted by trinaroberts about 1 year ago

Big thanks to all of you, and to all the other Identifiers of Syrphidae! I greatly appreciate the time and energy you put into identifying. Your prompt IDing of my Observations and especially your helpful comments have increased my knowledge of Syrphidae hugely, and motivate me to keep observing and learning!

Posted by grnmtn about 1 year ago

Thank you, thank you, to all the Diptera identifiers. Somehow flies became a favorite insect of mine and it is most likely due to the devoted group of iNat. identifiers mentioned here.

Posted by kneubaue about 1 year ago

Thank you to this kind and patient group for increasing my interest in flies! (and for putting up with all of my tags and questions for IDs haha)

Posted by mabuva2021 about 1 year ago

So appreciate all the work you put into those Toxomerus mysteries!

Posted by buggybuddy about 1 year ago

What a story! I love all the teamwork and collaboration that has gone on with this group. Yes, it's a great model for other groups. Let's hear about some others!

Posted by janetwright about 1 year ago

Wonderful feature on the hover fly identifiers! I have been fascinated by syrphids ever since I first began learning about them on iNat in 2020 and my knowledge of syrphids has grown greatly with the help of numerous identifications from the wonderful people mentioned in this article. Thanks so much to all of the identifiers of this special group of insects!

Posted by jmole about 1 year ago

Great article. Thanks to all of you for your help and guidance on IDing syrphids. The Vosper and Dankowicz guides are invaluable and I particularly appreciate (and enjoy) all the explanations provided by @trinaroberts when I'm trying to ID.

Posted by scoutingforplants about 1 year ago

Super profile! Thanks to all of you for helping me (and everyone else) learn more about this critical taxonomic group! Y'all rock!

Posted by srullman about 1 year ago

This is great and really inspiring! Sharing knowledge and being part of a welcoming team is for sure a big motivator in IDing. I love those ID-guides you guys made available... amazing!

Posted by ajott about 1 year ago

What an awesome community. I have learned SO much from these folks about flies. Another fun thing has happened -- when I'm out in the field with other folks, and we come across a fly, so many times, these ID'ers are brought up by name -- "Oh, I hope Trina looks at this..." or "I bet Even and Zack know this one right away..." "Catherine's gonna ID this one, no doubt." :)
Please know how grateful we are for all of your curation and teaching!

Posted by sambiology about 1 year ago

This is much appreciated. These folks have repeatedly helped me out, and I've definitely been remiss by not saying thank you to each identification, so let me do it here most publicly. Thank you!

Posted by matthew_wills about 1 year ago

These syrphid identifiers have all contributed to my knowledge and to my enjoyment and engagement with iNaturalist. Like @sambiology, I too have thought about these generous people by name, with a smile on my face, whenever I photograph a syrphid. This kind of thing is what makes iNaturalist such a great platform. Also thanks also to @tiwane for calling attention to these folks in such an engaging way.

Posted by sullivanribbit about 1 year ago

Well, syrphids are most of them very pretty, and, even though I basically still don't know one end of a fly from the other, I do photograph a lot of syrphids when the Korean Chysanthemums are flowering in October/November in the Conservatory Garden in Central Park, so I want to sincerely thank this team for all the ID help they have given me over the years!

Posted by susanhewitt about 1 year ago

It's so cool to learn a bit more about some of the people I've interacted with so much over the past few years and hear their perspective, thank you! I'm also happy to see so many people saying they have a greater appreciation for hover flies because of the identification efforts!

Posted by upupa-epops about 1 year ago

thanks to the existing regular IDers there were friendly and responsive people who would confirm, correct, discuss, and appreciate as needed

The syrphid identifiers community here immediately stuck out to me for this reason. I appreciate and enjoy every interaction I've had with Even, Trina, and the rest. Thanks for all the help and guidance!

Posted by sessilefielder about 1 year ago

Thanks so much to this crew for helping me learn more about these tiny critters! I am forever grateful for their efforts!

Posted by erikamitchell about 1 year ago

It is really great to see the people behind the names and read their stories. Inspiring work.

Posted by geographerdave about 1 year ago

Fantastic journal post here... thanks for all you do, everyone! I remember @upupa-epops's work early on and it was so cool reading the story of how the identification of syrphids evolved and formed into something so awesome.

Posted by joemdo about 1 year ago

@kuchipachi thanks to you, @lisnel @joemdo @arctic_mongoose for the on-the-ground help documenting those Florida ones!

Posted by upupa-epops about 1 year ago

I love the Fly Guide and have been so grateful for help I have gotten with my fly observations, but even more, being pointed to a particular link in it so I could work my way through on my own and then check back. After that I explored and went down multiple rabbit holes... I was thrilled to run into one of my photos in it. :-)

Posted by susan_kielb about 1 year ago

I love this post❣️

Posted by teellbee about 1 year ago

I'm truly grateful for the work these identifiers have done for me. I'm always on the look out for hoverflies now, and am gratified when they confirm that I've ID'ed one correctly.

Posted by cae1 about 1 year ago

👍

Posted by huttonia about 1 year ago

@upupa-epops it was awesome to be a part of it - definitely gave me a deeper appreciation for them :)

Posted by buggybuddy about 1 year ago

Great post!

Posted by derrell_d about 1 year ago

This work helps us all in appreciating the diversity in this group of living things and understanding their importance.

Posted by centex about 1 year ago

I loved this post and meeting Evan, Zacharay and Trina in particular because they have helped me many times to identify flies, especially syrphids and their larvae. I have learned so much from them and try to take better photos so that taxonomists like them might see the specimen characteristics they need to place them in the right genus and species, when possible. Adding to iNaturalist's scientific data base with sightings and phenological information is very important to me. And, while not about flies, I really am grateful to Evan and Zachary for helping me take proper photos to identify the Brood X Cicadas to species in 2021 in Louisville, KY. Before their comments, I only thought there was one species, but there were three, and I found them all here and documented them.

Posted by margaridamaria about 1 year ago

Thanks to each of you for all the fly ID help!

Posted by ammoph11 about 1 year ago

So nice to "meet" the wonderful people who ID my photos and to see how they became interested in an underserved group. Appreciate you!!

Posted by sarinole about 1 year ago

Great profile. I have benefited from the expertise of several of these individuals, both on iNaturalist and on BugGuide.

Posted by cotinis about 1 year ago

Thanks everyone for opening my eyes to the fascinating world of hover flies!

Posted by maragay about 1 year ago

Add a Comment

Sign In or Sign Up to add comments