Set water height to 0, get mountainous planet. Just so happens there's no template for it at the moment. (also, the mountain biome could use some work).
Yeah, i kinda wish they'd split mountain biome off from being dependent on water level, what if we want to make a flat desert planet? or a smooth ice ball?
Pretty sure that's just an old icon for tropical planets. EDIT: Huh, looks like it isn't. Some kind of combination between earth and tropical planets? Looks like in the concept art, the tropical planet icon was used for water planets and that was the tropical planet icon...
Forest, desert, tropical, jungle and mountain are all subbiomes of the 'Earth', 'Tropical', and 'Desert' planets, that appear based on height and distance to water.