Common jellyfish found to be two species after 175 years
US-based researchers using DNA sequencing have discovered that the common jellyfish, assumed to be a single species since its first description 175 years ago, are in fact two distinct species. Researches further found the ocean-based sea nettle jellyfish has 40 tentacles compared to 24 of its bayside counterpart. The ocean sea nettle also has a larger bell having shorter tentacles.