I logically think it is the ground.

Lots of sand and lost treasure
Not to mention the aliens

Atlantis nuff said

Sand and rocks mostly some vegetation and coral.

i think there might be diamonds or gold

Aliens of couse

Fish and sharks

Bin Laden

my answer would be osama bin laden megatron darth vader and hitler and not to forgot mermaids

lol

but on a more serious note idk lol maybe undiscovered types of plants like new types of see weed or something probally undiscovered planktons and algie maybe new fish but idk would it be suitable living conditions maybe theve adapted to it idk maybe well find out one day maybe not

me doing your mum c;