If you’re in a forest, the game spawns Pokemon related to that biome. If you’re in a park, or an urban environment, or a desert, or a city, or a grassland, or by a river/lake, or on a mountain, etc etc, the same thing occurs. For some reason or another, if the game has no allocated biome, the default is Helioptile. This happens in very remote areas, in the open ocean (or smaller islands in the ocean), or areas where the servers just has no data.
Non ironic answer, it would have been Helioptile.
If you’re in a forest, the game spawns Pokemon related to that biome. If you’re in a park, or an urban environment, or a desert, or a city, or a grassland, or by a river/lake, or on a mountain, etc etc, the same thing occurs. For some reason or another, if the game has no allocated biome, the default is Helioptile. This happens in very remote areas, in the open ocean (or smaller islands in the ocean), or areas where the servers just has no data.
As for why it’s Helioptile? No-one knows.