I lost 1 of my adults today. I have had her/him for over 5 years, but I don't know how old he/she was when I got him/her. I now have the 4 adults. I am not sure what happened. He/she did not look ill, so I am hoping maybe it was quick. One of them did turn black while going through a shed early in the week, but had gone back to bright green, so I don't know if it was the same one or not. none of them were losing weight or showing any signs of being ill, so I am baffled.