This is a black walnut tree. My brother noticed them while we were in the backyard. I have other trees that are not black walnut and do not see these bugs on them.

They are red with a black head. Their bodies have ridges on them. It's hard to tell because they are so small. Closer to a large grain of salt, or small piece of rice.

Mystery bug

Update: This is from Northeastern Oklahoma area. They have since disappeared. I'm not sure if the heat got to them or they turned into something else or what.

  • Its impossible to tell if these creatures have legs or not or whether they're larvae - do they and if so, how many? Is the tree healthy - there seems to be quite a lot of loose bark?
    – Bamboo
    May 20, 2018 at 2:24

3 Answers 3


This is a stab in the dark...Scarlet Malachite Beetle larvae. The size wasn't specified but red larvae with black head should be rare...ish? Scarlet Malachite


It would help if you told us where you are situated. However, they are likely to be cardinal beetles, possibly larvae feeding under the tree bark. Totally harmless cardinal beetles


Although I think stormy has a point about the odds of finding more red larva with black heads, I discovered another larva possibility: the walnut caterpillar (Datana integerrima), which seems to be a considerable walnut pest; so, I thought it might be likely.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.