Please get rid of having some creatures only available in parks. This would mean going to a real life park and as i play mainly at night this is (1) UNSAFE and (2) UNREALISTIC and VERY INCONVENIENT. Please think of players and keep the game strictly in the virtual world. Many thanks.
Update: I found a park that I could get to, but no Diplocaulus, even with a decent capsule.
HOWEVER, there a number of spawns across the street from the park. On a golf course. At a country club. Country clubs do NOT like it when you wander onto the 18th green. Not even for my favorite little dino. But the game thinks the cart tracks are roads, and kept spawning them.
Basically the parks are broken anyway. Better to just get rid of the restriction altogether. For the reasons started by other folks here as well as mine.