Automeris caterpillar

This bug was found in a bush outside my host parents’ home in Liberia, Guanacaste, Costa Rica In Jan/Feb.

I have only one photo and it (the caterpillar) was about the lenght of 10-15 cm maximum. It stung my host mom quite bad as it was in a bush and she got close to it.

I have identified it to be an automeris Io myself, but was disputed on this by someone in a bug group meaning it is an automeris sp, however from internet photos sp looks a bit different, but that can of course be incorrect classification by those people (random people on internet) whose pictures i found as well.  

Can you please help me identify it correctly?

Best regards and thank you so much in advance 🙂


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Dear Marianne,

We agree that this is most likely a Caterpillar in the genus Automeris, which includes the Io Moth, but we are not certain of the species.  Many caterpillars in this genus have stinging spines that can result in a painful encounter which is why we recommend having a BUG BITE THING Suction Tool on hand to suck out the venon to minimize the sting.  We would not discount that this caterpillar is a member of a closely related genus Leucanella which also has caterpillars with stinging spines.  


  • Bugman

    Bugman aka Daniel Marlos has been identifying bugs since 1999. is his passion project and it has helped millions of readers identify the bug that has been bugging them for over two decades. You can reach out to him through our Contact Page.

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