Environmental activist Homero Gomez, who fought to protect the monarch butterfly, has been found dead in Mexico two weeks after he disappeared, a local authority says.
Gomez's body was found in the western Mexican state of Michoacan. It was not immediately clear how he had died.
His disappearance had sparked an outcry in an increasingly violent country where activists are routinely threatened, harmed or even killed as a result of their work.
Human Rights State Commission of Michoacan had reported his disappearance on 13 January and commission official Mayte Cardona told Reuters he was "probably hurting the interests of people illegally logging in the area".
Michoacan's attorney general confirmed his death. One source at the state attorney's office, who declined to be named, told Reuters the cause of death had not been determined but that an initial review had found no signs of torture.
Urging the protection of their habitat, the reserve El Rosario Ocampo Michoacan, Gomez became best known among Mexicans for posting mesmerizing videos and photos of the orange and black butterflies on social media.
Millions of these butterflies make a 3220km journey each year from Canada to winter in central Mexico's warmer weather. However, the insects are facing new challenges linked to extreme weather and changing habitat.
Michoacan state is home to the country's largest monarch butterfly reserve, a World Heritage Site, as well as many rival drug gangs who battle to control smuggling routes through often-arid terrain to the Pacific and the interior of the country.