skunk shrimp life expectancy

i recently had a skunk shrimp die overnight. it molted the night before and as far as i can tell the tank is running properly. water quality is very good and all my corals seem very happy. the only thing that has happened is a water change the day before the shrimp molted. this was only a 2 gallon water change in a 50 gallon system. however the salinity did rise from 1.022 to just less than 1.023. i have had this shrimp at least a year, but less than 2 years.

 

I had an opportunistic fish eat both of my fire shrimp right after a molt. Is it possible a fish ate it? They have no shell protection right after molting.... :-/

 

no, i found it completely intact.