JOSÉ MARÍA MORELOS, Mexico — Hernán Reyes calls himself “negro” — black — plain and simple.

After some thought, Elda Mayren decides she is “Afromexicana,” or African-Mexican.

Candido Escuen, a 58-year-old papaya farmer, is not quite sure what word to use, but he knows he is not mestizo, or mixed white and native Indian, which is how most Mexicans describe themselves.

“Prieto,” or dark, “is what a lot of people call me,” he said.

This isolated village is named for an independence hero, thought to have had black ancestors, who helped abolish slavery in Mexico. It lies in the rugged hills of southwestern Mexico, among a smattering of towns and hamlets that have long embraced a heritage from African slaves who were brought here to work in mines and on sugar plantations in the 16th century.

Just how many people are willing to share that pride may soon be put to the test as Mexico moves to do something it has not attempted in decades and never on its modern census: ask people if they consider themselves black.