Zwei, there have been about ten no body prosecutions that I can recall. (This is a fairly significant percentage, much smaller population)
I'm sorry, I don't know how to link, but in my state, the partner of Bob Chappell was successfully prosecuted for his murder, on largely circumstantial evidence. His body has never been found, and she is still proclaiming her innocence.
The outback murder of British tourist Peter Falconio was prosecuted without his body ever being found.
Spine chillingly, the body of new born baby, Tegan Lane, ahs never been found, and her mother, Keli Lane, has just had an appeal turned down. This lady, who was a water polo player who hoped to make the Olympics, had no less than three "secret pregnancies", (whilst living with her partner, and being in bathers every day), and the second Baby, Tegan, was taken from the hospital, (of birth) and never seen again. What was seen again was her mother, Keli, on the video of a friends wedding, filmed three hours after they left the hospital! It was when she had the third baby, and adopted this out, (as she had done with the first), that authorities started to question what had happened to Tegan, and there was a nation wide search. Very sad.
In the Wallace case, there is mention of forensics that were not available to police at the time of the crime. Who knows what tests will be available in five, or even ten years?