I was lucky enough to get one shot of this behavior. It only lasted about 2 seconds. I was on the north side of the Columbia River across from Portland trying to get shots of this dragonfly species when this male flew up and landed right in front of me. Just as I got focused he performed sperm transfer and flew off. Most species do this while on the wing, so I was very pleased to capture it. The structural morphology of this secondary or accessory genitalia is unique to each species. It functions to transfer and store the sperm packets and then to transfer the packets to the female during copulation.
Nikon F5, 70-180 Micro-nikkor, 2 SB-28 flashes on a custom bracket and gunstock, Elitechrome 100
A close view of the accessory genitalia (hamules) of another species
Leucorrhinia glacialis. The large structure shaped like an open beak is is one half of a pair.
Leica MZ16 Stereomicroscope w/extended depth of field imaging system and processed with ImagePro Software