Figured this might be fun, to compile a list of distinctive animal species or general types that have not yet been made into pokemon. Prehistoric animals are excluded for the simple reason that we usually only get a few of those per generation of games.
One quick look through one of my more extensive animal encyclopedias and the following list was born. It should make for a good reply to anyone who thinks pokemon is running short on animals to base them on.
Feel free to note if I've made any mistakes in the list, and of course add animals not on it that you think would make good, distinctive, pokemon.
So without further delay here are a bunch of visually highly distinct animals species or groups that have not yet been made into pokemon:
Echidna (Cyndaquil looks more like a tenrec or shrew)
Naked Mole Rat
Colugo (flying lemur)
Giraffe (Girafarig is more an okapi)
Oryx or gazelle or some other lightly built antelope
Woodpecker (new bird we saw the schematic for may be one)
Anaconda (I always saw Serperior as more of python)
There are admittedly lots of snakes that could be done, but as pokemon making them physically distinct might prove difficult.
Monitor Lizard/Komodo Dragon
Rain frog (something small and cute compared to Seismitoad)
Giant water bug/Water beetle
Solpugid (sun spider)
Harvestman (daddy long legs)
Obviously I don’t expect examples of most or even a lot of these specific animals to come out in Sun and Moon but I do have hope that a number of them will. Honestly I also hope pokemon will continue what it has done so well in the past by combining various animals into a particular pokemon.