It's a bird! It's a plane! No, it's...

Tonight Brad and I were wandering around our yard, admiring the plants and checking how things were growing.  A bumblebee flew past, into the catmint flowers, which we need to cut back.  This turned our attention to the plant, and then to the bumblebee.  Or was it a bumblebee?  No, it was a hummingbird!  A teeny, tiny hummingbird.  No--hummingbirds don't have antennae.  What was that thing?

We looked closer and discovered a moth, which behaved and sounded exactly like a hummingbird, extracting nectar from the flowers of the catmint plant.  It also looked like a lobster, oddly enough.  Luckily, we grabbed the camera and got a good shot so we could identify our visitor:

Click on picture to enlarge

We then went online to identify what we had seen.  We saw a Nessus sphinx, according to this website. 

What's the most interesting creature you've seen in your yard?