freshwater jellyfish

Freshwater jellyfish can be found all over the world in lakes and ponds. They are small in size and may go unnoticed. An adult freshwater jellyfish reaches up to 1.9 cm/0.75 in in diameter, which is basically the size of a penny.
They live in colonies attached to rocks, tree stumps, and underwater vegetation.
Just like their salt water counterparts, these jellyfish have stinging cells too. However, they have not been proven to be able to pierce human skin.