Help me identify (non-experts welcome)

i think this is a hard question to answer specifically because each identifier will have a different workflow and may even use different workflows at different times. for example, if we knew there was an oak expert who exclusively identifies starting with observations at family Fagaceae level, then I would recommend Fagaceae as one possible answer to your question. but i get the sense that at least in my area, most plant identifiers are generalists. so getting things to class, order, or family may or may not help in their workflows. off the top of my head, in my area, there may be some people who occasionally do a little bit of specialization for Smilax, Oxalis, Carex, and Poaceae identifications, though i’m not sure if their identification ranges extend to your area. for things other than plants, there are a lots of specialists. so getting things to spiders, ray-finned fish, water bugs, bugs, grasshoppers/crickets, birds, dragonflies/damselflies, will likely funnel to an expert.

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Hi everyone,
Allograpta is a genus of hover flies with 2 species common in the US. At first glance they look pretty similar but I think after learning how to distinguish them they’re relatively easy from most observations. And there are a lot of observations of them as they’re very common.
The species are Allograpta obliqua and A. exotica. A. obliqua is common pretty much everywhere in North America, while A. exotica is common mostly in the southern half of the US (I think both are common in Central and South America, but there are lots of other Allograpta species there).

The most reliable feature to separate the 2 species is a section of the thorax called the katepimeron. In A. obliqua it is white, while in A. exotica it is black. It’s located about halfway between the base of the wings and the base of the middle and hind legs. It is marked with arrows in this image: https://bugguide.net/node/view/757809 (note that the face stripe mentioned there is not reliable for separating them)
Here are photos of each species as well to compare:
https://bugguide.net/node/view/1107106
https://bugguide.net/node/view/642078

Unfortunately most observations don’t show the katepimeron, but they almost always show the abdomen pattern. There are some features there that can generally be used to separate the species (copied from here):

  1. 2 narrow yellow bands/triangles near the base of tergite 2 (basically the very base of the abdomen) narrowing out towards the centre (present in obliqua, absent in exotica so that the base of T2 is all black).

  2. Narrow yellow band along the entire base of tergite 4 (obliqua has it, exotica does not).

  3. The “leaf-shaped” spots on the side of tergite 4 are usually closer to parallel to the centre pair of stripes, whereas in exotica they are usually closer to 45* or more away from them (exotica also has these spots connected to the centre pair of stripes like this more often, but both can have that).

  4. obliqua seems to often have more orangey-yellow stripes, whereas exotica often has more creamy or whiter yellow stripes.

That probably sounds complicated, but once you get an idea of what it looks like it’s not that bad. Just try to make sure most of those features are in alignment. The first image is a pretty clear A. obliqua, while the second one is a pretty clear A. exotica:
image


They are variable and there are some that are intermediate, but I think most are identifiable. You can get an idea of the variation possible within each species by looking through their image galleries:
Allograpta obliqua
Allograpta exotica

If you’re interested in helping identify these, here is a filter for all Needs ID observations of the genus in Canada and the US: https://www.inaturalist.org/observations/identify?taxon_id=118969&place_id=1%2C6712
If you want clarification on anything, please don’t hesitate to ask here or tag me in an observation. Feel free to skip over any that you’re not sure about.
Thank you!

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Thank you to everyone who’s helped so far! We are down 30+ pages from what was there last week.

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It would be helpful if this thread joined forces with the computer vision correction thread. I’d like to help them but I don’t know any of those species.

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If you check the flags linked on that topic, some of them have tips to ID, like:
https://www.inaturalist.org/flags/425901
https://www.inaturalist.org/flags/427929
https://www.inaturalist.org/flags/425598
https://www.inaturalist.org/flags/427440
https://www.inaturalist.org/flags/423140

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@arboretum_amy - Thanks very much for this guide - very helpful for a non-expert like myself. Most of the IDs I’ve been doing are fairly clear. I’ve seen a couple which seem ambiguous - sparse hairs and bud shape more like R coulteri. How would you classify this one?
https://www.inaturalist.org/observations/81458178

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Over time I’ve concluded the ones that look like R. coulteri in bud shape but have some sparse hairs are probably hybrid. In particular there’s a cultivar ‘White Cloud’ very common among non-wild plants which is known to be a cross of the two species. When I started out identifying I was using the rule of thumb that if it had any hairs I would call it R. trichocalyx, but now I tend to leave captive plants at genus if they have ambiguous traits.

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Thanks! I was leaning towards a hybrid as well.

Thanks for the heads up. You inspired me to have a go at the ones stuck at Asteraceae.

And now maybe I will be able to ID my own observation of this genus.

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a nother yellow daisy. Good luck.

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So true, and frustrating! I teach classes in grass identification, which is challenging but is do-able with the specimen in hand. I find I can’t teach others how to ID grasses on iNaturalist (at least, so far). The photos are frustrating. Certain grasses can be ID’d by gestalt (general appearance) but for many, the gestalt gives you an idea and then you check on a certain detail to rule out other possibilities. (e.g., That’s one of the weedy annual barleys, so I’ll check the auricles to ID or rule out the most common species.) In most cases, the iNaturalist photos don’t include the needed details, even by accident. Or more accurately, they don’t include those details in good enough focus to assess.

Early in my iNaturalist days, I thought I’d straighten out the identification of many grasses. I’ve actually helped with some species (mostly Phleum pratense and the species mistaken for it – I have a list of over 50 such iNat errors) but mostly I look longingly at the observations, wishing one of them showed the needed detail. Sigh.

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Well, I have been able to do a few. And in any case, I can frequently move then to tribe or subfamily; Cichorioidiae, especially, cannot really be mistaken for any other subfamily.

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…and now I understand why the Asteraceae get stuck there. It is because someone like me gets too frustrated with the sheer lack of confidence people have. I must have moved dozens of observations into American Asters. I mean sure, there are lots of confusing species, and I don’t know most of them either, but come on – I at least know that they are asters.

And how many observations did I see of foliage without flowers that could only be Sow-Thistles? Again, nothing wrong with leaving it at genus. Or for that matter, even if you don’t know the genus, if you see one that is really, really prickly, you are pretty safe in calling it Thistles and Allies, or even be a little bolder and say Thistles and Burdocks. Or, if you live in North America, how can you not know Black-Eyed Susan? Sure, there are other species of Rudbeckia, but those would only bump it back to genus, which isn’t that far.

What really floored me, though, were the number of Oxeye Daisy that were left at Asteraceae. I mean, it’s not like that is a rare or obscure species; it’s pretty much the quintessential daisy.

People lack confidence, and they hedge too much. It is as if they are so afraid of giving a wrong answer, they give an essentially useless answer instead. You can always correct it later if your notifications show that others have gone a different way with it.

I’ll keep at these a bit longer, but I’m getting discouraged by the above.

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I think there’s a tendency for many people, myself included, to largely avoid IDing to anything other than kingdom/phylum/class/order/family/genus/species, and for many asteraceae it is easiest to get to one of the tiers between family and genus. In fact, for me, one of the few exceptions when I’m clearing unknowns is I usually identify anything that looks remotely like a dandelion to Tribe Cichorieae. Possibly I could be more aggressive there, but there’s a fear of ‘you don’t know what you don’t know’. I like the idea of this thread in making a list of things I shouldn’t be afraid to ID to specifically.

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Prickly daisies - you mean Berkheya and Cullumia?

Oxeye daisies we only see in gardens here = Casual.

Quintessential daisy? This one is huge and unmistakable ;~)
https://www.inaturalist.org/taxa/404420-Osteospermum-moniliferum

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And for genus within tribe astereae, symphotrichium? eurybia? aster? erigeron? However many other options there are? I suppose sometime I could take a few hours to learn to sort those genuses, or if someone told me there are some that are easy I could do those, but its certainly not just a confidence issue that I’m not doing it.

ID what you are confident of, and what you enjoy. Every little helps.
Follow your notifications, and your skill will develop.
I mostly go to plant genus, and leave those who can to sort out the species.

The North American taxa formerly in Aster were split off as Symphotrichium; so for that, I go by what hemisphere it is in. Erigeron doesn’t look much like Aster/Symphotrichium to me – the leaves are very different.

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