The Mining Gazette is reporting that the U.S. Fish and Wildlife Service just added the silver carp (Hypophthalmichthys molitrix) and largescale silver carp (Hypophthalmichthys harmandi) to the country's list of injurious species (via the Lacey Act). That means no more state-to-state transport and no more imports of these species into the USA from other countries. The silver carp's "poisson non grata" status becomes official on August 9th. It is the first carp to make the injurious species list (a similar query was made for black carp (Mylopharyngodon piceus) back in 2003 but still doesn't seem to have gone anywhere).
Interested readers may want to travel back in the ISW time machine to fall 2006, when the request for comments regarding the status of the silver carp in the USA was published. If you want to go right to the USFWS ruling, the pdf is here.