With rising temperatures, jellyfish blooms have been increasing in the world’s oceans. Now there’s a threat to America’s freshwater lakes. Imported from China in Fish DeliveriesThese freshwater jellyfish are called Craspedacusta sowerbii and are not as big as you might see in the ocean. Freshwater jellyfish come from China. Photo by Marat Gilyadzinov on Unsplash Freshwater jellyfish come from China.