Identifiers, what parts of organisms are helpful for identification?

Hello again, inat!

I am currently quite invested in plants and I have learned that the following can aid in identification (correct me I’m wrong please!):

  • The flower head (Petals, colour, stamen, pistils, shape, diameter, clumped together/spread apart)
  • Back of the flower head (Calyx/sepals, hairs)
  • Leaves (Shape, vein patterns, differences between leaves nearer the base and the top, pattern e.g. paired and opposite, hairs)
  • The “nature” of the plant e.g. does it creep along the ground? Does the plant tend to grow relatively straight?
  • The stem (Hairs, shape)

Of course there is probably many other ways to also aid in identification of plants, but this got me thinking when I was on a walk recently about other organisms. What identifying features should we be looking out for when taking a photo of anything really. I’ve noticed myself going around and finding organisms but I don’t exactly know what I should be taking a photo of. For example, when I took a photo of a razorclam I was told that I needed both sides of the shell. On top of this, I found an observation of one that someone had taken and there was quite a lot of parts to the shell that were relevant for identifying.

Any information on any organism is welcome!

For most big groups you can think of there’s likely already a topic on how to photograph them for ids.


At least 3 views, gives you a fair chance of including what you need. Until you specialise and know what you need for this one.


I think you’ll find much of what you’re looking for here:

particularly the forum post linked within it here:

I could swear I remember a Google Doc or something similar that was organized by taxa, but I’m unable to find it. If it does exist, hopefully someone else drops it in here!


For winter trees: Branching pattern (opposite, alternate etc.), bark on mature trunk and young twigs, needles/cones on conifers (including underside of needles, attachment to the stem), on deciduous trees any leftover leaves/fruits or modifications such as thorns, close-ups of winter buds, leaf scars and other markings on twigs. An overall view of the entire tree is nice but often not possible in a forest setting. Sometimes a cross-section through a twig to show the shape of the pith can be very informative but in the interest of leave-no-trace I don’t like to encourage damaging plants just to get an ID on them. A single picture of mature bark is often all that people post on iNat and with a few exceptions of very characteristic bark it’s hard to do anything with that for tree IDs.


Oh, it was in the guide I sent I just didn’t look hard enough. This guide is absolutely fantastic as it breaks down how to photograph various taxa and is well organized

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Fungus - oh man. The more details the better.

For cap & stem shrooms, you want at minimum the top of the cap, the underside (is it gills or pores?) and the stem. But there’s so much more that can help

-Connection point between the stem and the gills.
-Substrate. What is it growing on. Straight out of the soil? On leaf litter? Mulch? What kind of tree is it growing on, is it a conifer or deciduous? Do you know the species of tree? Do you know the species of associated trees around it.
-In situ pics help greatly
-Presence or absence of a partial or full veil or cobwebby remnants of a veil.
-Base of the mushroom. Is it thin or bulbous? Is there the presence of a sac-like remnant? (a volva)
-Spore color. A spore print helps, but you can sometimes see spores below the mushroom, either caught on the cap of another shroom, veil remnants, or even the ground.
-Is there bruising? what color does it bruise, how fast does it bruise, where does it bruise? Some mushrooms will bruise on the cap, underside, stem, or any combination of the three.
-Potential chemical reactions with ammonia/potassium hydroxide/iron salts (does it change color?)
-Pictures of both young & old specimens if you can get them.
-Taste: Nibble and spit a piece of the cap - is it spicy? bitter? NOTE: I wouldn’t suggest doing this with all mushrooms unless you know what you’re doing, but even a death cap won’t kill you as long as you don’t ingest it. Taste is mainly an important identifier for some bolete species, as well as mushrooms in the family russulaceae
-Microscopy of the pores can help too if you have one, some species are really hard to get down to the species level without this. (I don’t have a microscope though so I don’t really ever try this)
-cut it in half. This can help separate some morels from gyromitra species, as well as tell chantarelles from some of their look alikes.

(I’m not perfect at all or most of these, but I’m trying to get better.)


This is absolutely perfect!

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Which doesn’t necessarily mean lots and lots of pictures. Here you can see a set of just three pictures that captured most of the quoted features: Deciever. The bruising color can potentially be added to a picture of other features, too.


This is definitely all good stuff for plant IDs, and I’d like to add that measurements can be a big help! A lot of plants are identified at least in part by the length or width of specific elements, usually in centimeters or millimeters (but of course other units can be converted). For example, there are a couple Rhynchospora species that are most easily distinguished by the length of the white spot on their bracts, and a major part of the Smilax identification key I’m most familiar with involves measuring petiole and peduncle length. Grass IDs often involve a lot of really precise and tiny measurements in the spikelet, and observation of very tiny features there. The way the leaf attaches to the stem is also important there. Also, some plant species are distinguished more easily with fruit than with flowers, and a few even require both for a really confident ID. Tendrils can also be important if the plant has them - this is a big deal in Vitis, for example. The underside of leaves is a pretty common identification feature, too. Sometimes, having a good visual on both basal and cauline leaves also helps. With ferns, it’s often important to have a reproductive frond and a good view of the sori, and the rhizome can be helpful to have as well.

Every species has different ID requirements, so if you can get a good familiarity with plants in your area that helps a lot, especially if you can figure out what the most popular dichotomous key(s) are in your area and get ahold of them to look through.


I’d like to turn the OP’s question on its head a little: how best can we photograph and document our observations so that they can serve as ID tools for others seeking to identify a specimen?

For example, Mormon Tea is dioecious, and so a photograph of female flowers (cones, actually) on one plant will confuse someone trying to ID a plant with male flowers. One solution is to link the obs of the female-flowered plant to an obs of a plant with male flowers.

Another example: some plants bloom before they leaf out, or, like Ocotillo, leaf out very briefly after a rain and then shed the leaves quickly as the ground dries. One potential workaround would be to photograph the same plant in one condition and then again when it’s in another, and link the observations (“to see this plant in leaf, check obs######”).


Clear photos of wing venation (if visible) can be helpful for insects! The underside of the abdomen is also necessary for some moths (eg. Desmia sp.) so that’s worth getting when possible as well.

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don’t overburden yourself, but the short answer is: be curious. anything you notice, and I mean anything that makes your subject look different than related species may be useful. in time you’ll learn what is most important so you can be more efficient. we’d rather have extra photos than be missing something.

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