As those who follow me on Twitter may know, I recently moved in to a new apartment. My old apartment balcony was made of concrete and metal, but this new one has a wooden railing.
On the first day I got the keys for the new place and went exploring, I noticed little piles of saw dust underneath some of the rails outside.
.
.
Previous experience (having a wooden deck as a child growing up) told me that the dust was the result of carpenter bees “drilling” into the wooden rails. Not too much of a mystery there! The mystery comes, instead, from the insect that I then saw flying around the railings.
.
.
It was hard to get a picture of, and unfortunately this is about the best I have. Is this a carpenter bee? In this case, previous life experience would tell me no! All of the carpenter bees I have seen look like pretty much like other bees. For example, here is a picture from a pest control site showing what a carpenter bee looks like vs. a honey bee. There is a bit of a size and shape difference, but the coloring is very similar!
.
.
The insect I saw, however, was all black. A google image search reveals that some carpenter bees are black, but according to the Pennsylvania State University Entomology department, there is only one species of carpenter bee in Pennsylvania–Xylocopa virginica. This species is one of the kinds with the stereotypical yellow and black “bee” markings.
There is one more strange thing about the insect I saw. That head shape! Again, I wish I got a better picture, but in the image above you can see that the head is much narrower than the body, which doesn’t seem to be the case in carpenter bees.
So what say you, readers? Any ideas what this mystery insect might be? Do you think it is a carpenter bee after all? I should add that, while I saw it flying around the area with the wood shavings, it never went in any of the drilled holes. I searched for insect predators of the carpenter bee, but couldn’t find anything. I should also add that I have never seen this insect again after that first day! Could it just be a different shaped male of the same species? What do you think?
I am going to end with a picture I found on the U.S. Forest Service website during my search that I thought was too amazing not to share. It’s a picture of the smallest bee (Perdita minima) on top of the largest bee (a female carpenter bee)’s head.
Photo Credit: Dr. Stephen L. Buchmann
.
Amazing!
So what do you think, nature sleuths? I’m sure we can solve this mystery together! Please leave any guesses or information in the comments! I would love to know what it was!
Backyardsafari's Blog 
The insect in your photo is too blurry to make out, but it could be a beefly. It seems to have very skinny legs; bees have thicker ones.
When you use somebody else’s photo, such as the one you borrowed from the Forest Service, you should request permission and give credit to the photographer. I don’t see Steve Buchmann’s name anywhere here.
Read the conditions of use of that website: . . . “If an individual photographer is listed, we ask you to also credit them by name.”
Hi Pollinator!
Thanks for stopping by our website and for the beefly tip! I wish I had been able to get a clearer picture at the time.
I also appreciate the information from the Forest Service’s website! I certainly wasn’t trying to get credit for the photo and had thought people would visit the link included in the post. I didn’t read the conditions of the website carefully enough, and will edit it to include Steve’s name! It is a fantastic photo.
Hope you stop by the site again soon!