Salamanders are no longer allowed to cross state lines in the U.S.—but the United States Fish and Wildlife Service says it’s for their own good. According to The New York Times, scientists are trying to prevent the spread of Bsal, a lethal fungus that has been infecting salamanders in Europe. The new rule, which goes into effect on January 28, will make it illegal to transport salamanders into the United States from abroad or from state to state. Offenders could face fines and prison sentences of up to six months.

The new rule sheds light on the impressive diversity of salamander species in America, and it was passed by the Fish and Wildlife Service with impressive speed—in part because of the sense of urgency that surrounds the need to preserve the 190 species of salamander currently living in the United States.

“With the highest biodiversity of salamanders in the world here in the United States, we’re very concerned about the risk this fungus poses,” David Hoskins, assistant director of the agency’s Fish and Aquatic Conservation Program, told The New York Times.

Though salamanders are small, the impact they have on their environment is significant: “Any harm suffered by salamander populations could have widespread ecological consequences,” explains The New York Times. “Salamanders are important predators of invertebrates like snails, worms and insects, and they make up a huge portion of the biomass in many forests.”

[h/t: New York Times]