Disney/Marvel Studios

The US Department of Agriculture included Wakanda, the fictional home of the Marvel superhero Black Panther, alongside Panama and Peru in a list of official free-trade partners.

The agency removed the high-tech African nation after a researcher spotted the gaffe while using the USDA's Tariff Tracker and tweeted screenshots of the listing and Wakanda's supposed exports.

"The Foreign Agricultural Service staff who maintain the Tariff Tracker have been using test files to ensure that the system is running properly," the USDA told NBC in a statement. "The Wakanda information should have been removed after testing and has now been taken down."

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President Donald Trump may be preparing to slap tariffs on Wakanda, the fictional homeland of the Marvel superhero Black Panther.

That's one explanation for the US Department of Agriculture's removal of the high-tech African nation from a list of free-trade partners that includes Panama and Peru in addition to other actual countries. In reality, officials uploaded Wakanda and its supposed exports to test a tariff-tracking tool and neglected to remove it.

"Wakanda is listed as a US free trade partner on the USDA website??" tweeted Francis Tseng, a fellow at the Jain Family Institute, after he spotted the gaffe while using the agency's Tariff Tracker tool.

Tseng tweeted a screenshot of the list and another detailing Wakandan exports such as horses, goats, and sheep. The "Heart-Shaped Herb" that gives Black Panther his superhuman strength and agility didn't make the cut.

"I definitely did a double take," Tseng told NBC News. "I Googled Wakanda to make sure it was actually fiction, and I wasn't misremembering. I mean, I couldn't believe it."

Wakanda was added to the USDA Tariff Tracker after June 10, NBC reported, and removed Wednesday.

"Over the past few weeks, the Foreign Agricultural Service staff who maintain the Tariff Tracker have been using test files to ensure that the system is running properly," the USDA said in a statement to NBC. "The Wakanda information should have been removed after testing and has now been taken down."

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