R.I.P. Fat Guy

We were wondering why it had gotten so fat. Did it explode? Did it have a parasite? No way of knowing. Fat Guy was so named because he (she?) got inordinately fat. We figured either pregnancy or gluttony. This morning we discovered Fat Guy floating. When netted, we found nothing but head and back intact. The rest of it looked like it had just "exploded" away. Gone. Nada. Nothing but bones left. Very weird.