A microscopic creature that cleans food particles from the mouths of lobsters doesn't seem to have a place in the animal kingdom, Danish zoologists have discovered. "This is a big, big deal," says TIME's David Bjerklie. "Scientists will be scratching their heads about this for a long time. They'll wonder why something so radically different has developed and when it started. One thing is certain, a lot of scientists are going to start looking into crustacean lips for a long time." The discovery of the creature, called Symbion pandora, was made by Danish scientists Tom Fenchel and Claus Nielsen in the 1960s. But because Fenchel and Nielsen did not have sophisticated equipment that could adequately analyze their findings, they were unable to recognize that the creature did not belong to any other of the 35 existing categories of phyla. In 1991, two other Danish zoologists, Peter Funch and Reinhardt Moebjerg Kristensen, picked up where Fenchel and Nielsen left off and and they found that, indeed, symbion was a newly discovered creature. Their findings were reported in Thursday's issue of Nature.