Key to arthropods down to Isopods

When ID’ing on iNat I often run into observations of non-isopod groups ID’d as isopods, so I figured I’d make a key that can help people rule out other arthropod groups when making an isopod ID.

Why I did this in the span of a day during midterm week eludes me…


This is nothing short of being amazing!

PS: I think it’s called procrastination ;-)


Thank you for this, I hope it helps people better understand their differences.

You should add some photos to help us non-experts… after your final exams are done!


This key is really cool, but also very technical. I think you’re going to run into problems of people who aren’t very familiar with arthropods trying to read it, encountering half a dozen words they don’t know, and getting stuck. Heck, I know a lot more about arthropods than the average person, and I still see a bunch of words in here I don’t know. It might be good to define some words, and also use simpler wording when possible; for example, “appendages frequently biramous” could instead just be “appendages frequently forking into two”. I have to imagine anyone who knows all these words already can probably tell the difference between an isopod and an Annelid worm.
Lots of useful information for telling some members of some groups apart, though, I’ll have to hold onto this. I don’t mean to sound like it isn’t useful! It just seems to me that the Venn diagram of people who recognize most of these words, and people who need help telling isopods from other creatures, probably has only a very small section in the middle.


Thanks for the help! I’ve altered some couplets and drew figures for 2 of them to start making it a bit more beginner-friendly


Those are some excellent improvements! That should make things much more accessible to a wide variety of knowledge levels.

1 Like

What an excellent key! I really appreciate people who put the work into making accessible keys like this, they’re great resources for all naturalists.

1 Like

This topic was automatically closed 60 days after the last reply. New replies are no longer allowed.