Why are some taxa so under observed?

I was looking through taxa under Bee Flies (Bombyliidae) and I found several genera that had 0 observations. Looking through other taxa under Insecta I found more large groups that had no observations. I would not be surprised if it was a particularly rare single species that had no observations, but several large groups of insects having no observations is surprising to me. I also would not be surprised if the taxa with no observations was something difficult to photograph, like a deep sea mite or something strange. But, insects are typically available to photograph for someone out there. So, maybe it’s a silly question, or an unanswerable one, but why are there so many insect taxa with no observations?


Hi, welcome to the Forum!

To answer your question, basically, some species are more difficult to photograph, or to identify.

To troubleshoot what may be causing the confusion, I think you’ve got your filter set to a specific location, which means that some taxa (species / groups of organisms) simply have not been observed in that place … yet!

Would you mind uploading a screenshot so I can see what you’re looking at? Or links to the relevant taxa?


Ditto to trh_blue’s answer. Many insect genera are difficult to identify with a photo. There are a lot of flies and beetles that are hard to even get to family level ID from a photo.


Very few people study bee flies. Some genera like Villa haven’t been updated in over a century: “This genus has not been reviewed in NA since Coquillett (1892)” (BugGuide).


Another problem is getting access to identification information. I’ve got several internet sites for moth identification in North America that I can use, but if I decided to concentrate on Mayflies or Tricoptera I wouldn’t know where to get identification information. Many insect groups need microscopic examining to identify them, and I don’t have a microscope. And I’m not wild about killing specimens just to identify them. Imagine millions of users sampling organisms. We’d have more identifications, but fewer wild organisms.
So there are probably multiple reasons why a specific taxa is not represented in the iNat database.


A significant part of it also may come down to the distribution of the iNat user community. While the taxonomy is global, more than 70% of the user community is based in either Canada or the US. A few other areas such as New Zealand and South Africa have good representation.

But with other areas of the world being underrepresented, this impacts the degree to which taxa in those locations get submitted and/or identified.


Thank you for the great answers, that makes a lot of sense! Maybe one day identification information will become more accessible and in general, more useful!

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That’s what is happening anyway, thousands of entomologists do it, data is more valuable than the life of one specimen, some rare species really need protection but don’t get it cause nobody sampled them from areas where they live. But you need to study before catching anything, many things are identifiable with good pics of alive object.


I agree with @cmcheatle, with many species living in Southern regions (for Northern Hemisphere) we lack people here and some countries are fully inaccessible because of wars going on there for decades, and those countries are very bio-diverse. We need many info about flies in general, not many people look after them plus some people post only to websites like BugGuide, I’m glad each month we are getting more experts to id these groups and it leads to success in numbers of seen species.

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I think it’s fine for a specialist to kill an animal if needed for ID, but we shouldn’t be encouraging laypeople to kill things just in case it might help with ID. Someone who doesn’t know what they’re doing will likely kill many animals unnecessarily. In some cases this won’t overly affect the population, particularly with inverts, but there are better methods.


I have a possible explanation. Without impressive, close up shots, some families cannot go to genus. Sciaridae is one example, as the taxonomy needs a rewrite. Some other taxa are inaccessible to most people, such as cave-dwelling inverts, or underwater creatures. Take for example the class Monoplacophora. It is extremely common at the abyssal and hadal zones of the ocean, however it is inaccessible. Hope this helps.


Again, thank you for the helpful answers to my question. My two cents on the collection of specimens: I think that amateur naturalists (like myself) should basically never collect specimens. While some species are very plentiful, I think that it’s useful for beginning naturalists to practice hands-off naturalism regardless of the severity of killing a single specimen. By practicing this hands-off style of observation, one might learn a tad less about the specimen but more about the way it interacts with the world. Specialists, well, they know what they are doing and that’s a different story.


Could not resist adding my two cents, too. @brandon261 opinion on not collecting the specimens for the sake of fun, even if it includes some learning, is very commendable. Professionals do collect and kill, but it is for the knowledge, which often includes basis for conservation of biodiversity. And them, there are much lower numbers of professionals, when compared to all naturalists, so the damage is much less.

About the identification information. I see at least three problems: i) inaccessibility to non-specialists (sometimes difficult even for specialists, but we have our networks which make things easier); ii) absence of such (there is only some data scattered in plethora of small scientific papers); iii) ID keys are written in very short statements, important details are skipped, they are difficult to use for laymen, no illustrations. Reasons? 1)There is lots of talk how great citizen science is, how helpful for biodiversity research, but nothing is done to help the citizen scientists. Example: in a recent project of one of EU biodiversity –related program projects there was a big chapter on citizen science, where there was campaigns planned how to involve people in recording biodiversity (fliers, leaflets, brochures, information campaigns, etc.), but not a single word about identification resources: keys, new guidebooks, internet sites etc. 2) Researchers? They just cannot do this anymore, because they have to publish in the high-ranked journals, meaning phylogenetic or ecological research. Just check, how many universities worldwide will keep a biologist, who is a great expert of one group of organisms, is good in field and produces field guides and keys. In my field of work, during the last decade I saw a virtual death of field lichenology in at least one region of Europe.


What happened at iNaturalist ( no new development in guides https://www.inaturalist.org/guides ) also happened at other citizen science sites. I dunno why but it is obvious field guides is another playing field. These decisions are already made before Computer Vision became popular.


I mostly focus on plant observations and identifications, but I notice this too.

I think in the world of plants, there is a bias towards “interesting” looking species, i.e. things with conspicuous flowers, leaves, seedpods, or other plant parts that make them stand out visually.

So, for example, small plants with wind-pollinated flowers, like Acalypha sp., smaller nettle-family plants, and many grasses, go under-reported. A classic example is this grass:


It’s so common, within its range you can find it in most people’s lawns or gardens, AND it’s common in the wild. But iNat’s observations of it are sparse. A lot of this is that people don’t know how to ID it…but more broadly, it’s a grass, and people don’t even pay much attention to grasses, especially small ones with a not-very-showy inflorescence or seedhead.

I think things that incentivize people to report more species and build their life list, can help address this. For example, I am active on eBird and eBird has a feature called “county ticks” which counts how many birds you have observed in individual counties, so the tick goes up whenever you see a new species in a new county for you.

This pushes users to do things like reporting pigeons and house sparrows (which serious birders often ignore) in under-birded counties. And thus helps track their populations.

I try to do this on iNaturalist, but I think one user can have a limited effect. I would love to see a feature kinda like “county ticks” which encourages users to report species in new regions.

But it’s also hard. Learning grass ID is hard. And it was years before I got good enough at plant ID to start exhaustively learning the small, inconspicuous weedy plants. They are often tricky because the flowers are indistinct, and if they’re not blooming it’s even harder. So even if you want to do it, it’s a ton of work.


I agree that ID is under-emphasized!

I am trying to respond to this. For example when I started bplant.org, I initially was thinking of focusing more on user-reported observations, but iNaturalist already does this so well and I didn’t want to compete or re-invent the wheel, so instead, I’ve been focusing more on ID.

I’ve been publishing a ton of plant ID guides, sometimes sharing them on iNat discussions when relevant, and they’ve been hugely successful!

I focus on commonly-confused species.

I would love to see more on-site instruction though, from iNaturalist, pointing people to ID help. For example, a while back I didn’t know about BONAP. Their county-level range maps are one of the most useful resources I have found, as they’re much more accurate than the USDA’s maps (which would be pretty useful on their own if BONAP didn’t exist.) A lot of users know neither of BONAP nor the USDA maps. Pointing users to BONAP would be useful.

For birds, pointing users to eBird and explaining basics of how to filter by county and then look at the bar charts showing frequency at different times of year, can be super helpful.

For insects, pointing people to bugguide.net is helpful. I am terrible with insects but I sometimes find between iNat’s AI and bugguide.net I feel confident enough identifying something.

At the same time I understand there is a limited amount people can do in the official iNat documentation. iNat has a super active community and people can and do share ID guides and tips in comments and in the forums. I think if a user is committed, they’ll stumble across this info pretty soon.


Simple explanation to that: a) field biologists are decreasing at a rate of biodiversity decrease; b) to write a good guidebook/create a good internet site takes much more time than to write a paper in a well-cited journal, for which researchers are evaluated and paid. Who will write the fieldguides under such conditions?


Can you make a feature request for the county ticks? It seems like an awesome idea, or something like which counties you still need to Inat in or something like that. Sorry for getting off topic.


I have thought about it. I would love the idea of county ticks implemented on iNaturalist.

To be honest though I would strongly prefer that instead of doing county ticks, instead the site use something like the US EPA’s level 4 ecoregions, which do not correspond to county boundaries. Here is an example with a map of PA I generated, using these regions:


The regions tend to be relatively homogeneous, i.e. you tend to find the same species on the sandstone ridges, as in the limestone/dolomite valleys, etc.

Canada has something even finer-level than these ecoregions, they have ecozones (which I think correspond about to these regions) and ecodistricts (which are even finer.)

I know it would be a tremendous amount of work to work with these datasets but it is doable.

Someone has actually already imported a large portion of the level 4 ecoregions into iNaturalist, where they are usable as “places” and they can be used in certain types of searches. I don’t know about Canada’s ones.

I hope that everyone here wants to be a specialist of some level in taxa they observe, most random users don’t visit forum anyway. If you want to study biodiversity aroun you it’s needed to read many books and many keys, it’s not that hard to remember which groups need more specific shots that you can’t get from a fast moving alive specimen. And I wouldn’t kill any if there was a way to do it on live (and I do it where possible).
e.g. this one https://www.inaturalist.org/observations/49302822, in need of checking by professional, but there’s a whole tribe of similar-looking insects, and by similar I mean very similar on the level it’s hard to distinguish one genus from another on full-body pics (and on 1k+ obs we have only 20 species now that shows how hard id is), and they’re not even small, they’re big, but nobody with collection data added this species before, and mine will be waiting for ages to find a review, but it is a valuable data impossible to get with alive specimen. And again, I hope we all research before going out, it helps a lot not only in such cases, but to generally find species.