Bat, Costa Rica. I shot this bat in the dark with a flash setup. The bats would fly out of the dark and into the murky red light we were using, giving just a split second to react, and making it difficult to trip the shutter at the exact instant. Perhaps some sort of automatic trigger would have been better, but the bats were coming from all directions. This was the best frame out of many, many tries. I don't know the species. I even consulted a bat expert, but they weren't sure either.