The two-inch snail darter became a symbol for regulatory overreach in the 1970s. New research suggests the fish was not an endangered species — or even a species.

Sophon Heng reportedly knew the fish had been illegally traded, which violates U.S. laws designed to protect endangered species, court documents say.

Federal wildlife officials on Tuesday moved to add the monarch butterfly to its endangered species roster, citing decades of steep population decline of the striking black-and-orange insect.