Beetle on lawn
Location: Bowie, MD
March 31, 2012 12:20 pm
My daughter’s (besides being totally creeped out by them) would like to know what this was.
Signature: Dan Delaney
Oil Beetle with Fire Colored Beetles
Dear Dan,
The large beetle is a Blister Beetle called an Oil Beetle in the genus Meloe, most likely a female. The smaller beetles are a different species, and we suspect they are not even in the Blister Beetle family. Blister Beetles exude a compound known as cantharidin as a defense mechanism. Chatharidin can cause blistering in skin. The other beetles might be Soldier Beetles, and they do not have a chemical defense. They might be harvesting the cantharidin to use since they cannot produce the compound. We will keep trying to identify the other beetles.
Update: March 31, 2012
Thanks to a comment from Mike, we are happy to learn that these are most likely Fire Colored Beetles, though BugGuide does not provide any explanation for this behavior. We also found a photo of Pedilus terminalus on Meloe posted to BugGuide and the behavior is explained here on BugGuide.
I like ThisRelated posts:
I wonder if they could be fire colored beetles. I sent in a picture once of a blister beetle with smaller beetles all over it like this and the smaller beetles ended up being identified as fire colored beetles. I’m no expert here. I just thought I would share my experience with this phenomenon.
Here is the link to the bugguide page on what mine were. http://bugguide.net/node/view/168899
Wow, thanks Mike. It looks like you are probably right. We are linking to the genus page on BugGuide because there is a bit more information than on the species page.
Your welcome, bugman. I saw this post and it reminded me of my encounter with this behavior , so I went back and looked at my pic to see what the small beetles looked like. They were nearly identical to the ones in this post, so I thought I’d lend a helping hand.