On the off chance you needed another reason not to use live eels in sex play, consider the story of a man in China's Guangdong province who was hospitalized after an eel -- apparently being used in sex play to imitate a porn the man had been watching -- slithered up his anus and proceeded to wreak havoc on his innards as it tried to chew its way out of his body to freedom. Which, if you're the eel, is a perfectly reasonable reaction here.
Proving once again that there are still places on our own planet that have yet to yield all their secrets, scientists have discovered a unique eel off the coast of the Republic of Palau in the Pacific Ocean. This eel has been dubbed a "living fossil" due to its unusually primitive features. These features led researchers to create a new taxonomic family to classify the eel in relation to other eel species. The eel, described in the researchers' paper in the Proceedings of the Royal Society B, is an 18cm-long female, collected during a dive in an 35-m deep underwater cave. The species was named Protoanguilla palau, according to the new family, genus, and species names bestowed by the researchers. According to the researchers from Chiba's Natural History Museum in Japan, the Southern Marine Laboratory in Palau, and the Smithsonian Institute in Washington DC, the eel likely embarked on an independent evolutionary history millions of years ago.