Just tried a total restart on the Moto G and still the same issue. Did a little more digging - appears to be an issue many are reporting:
https://www.reddit.com/r/pokemongo/comments/4rvq0j/pokedex_problems_on_android/
https://www.reddit.com/r/pokemongo/comments/4s6j50/pokedex_is_broken/
Looks like we'll need to wait for the fix.
Seems a restart was only a temporary fix for me anyway, it was screwed again this morning, good to know its not just us.