Marcia Fuqua, pictured second row and third from the left, poses for the Goucher College's 1952 International Relations Club picture. Fuqua, who now goes by the name Martha Fouquet in homage to a French ancestor, was a fine arts major and originally from Baltimore. (Goucher College Archives)

Robert Musser was living at Marcia Fouquet’s Fairfax County home in the early 1980s when, he said, he noticed a tiny painting with an ornate gold frame. It had a small plaque bearing a name he still remembers 30 years later: Renoir.

He asked Fouquet where she’d gotten the painting. “She said it came from a museum in Baltimore,” recalled Musser, 61, a mechanical contractor who dated Fouquet at the time and now lives in North Carolina. “She said it was a real Renoir, that she owned a Renoir. . . . She never told me how she acquired it.”

Musser’s account, along with similar recollections from two other former acquaintances of Fouquet, adds to the uncertainty surrounding the “flea-market Renoir,” a painting whose murky provenance has fueled an FBI investigation and an art mystery.

The 51 / 2-by-9-inch landscape, “On the Shore of the Seine,” burst into the national news in September when Fouquet’s daughter, Martha Fuqua, tried selling the piece through an Alexandria auction house, which believed it could fetch as much as $100,000. Known then only as “Renoir Girl,” Fuqua told reporters that she had unwittingly bought the Renoir in a $7 box of trinkets at a West Virginia flea market.

Days before the September auction at the Potomack Company, the Baltimore Museum of Art found internal records showing that the Renoir had been stolen while on exhibit in 1951. The FBI seized the painting from Potomack and opened an investigation into the theft, which a spokeswoman declined to discuss for this article.

This handout image provided by The Potomack Company auctioneers shows a painting by French painter Pierre-Auguste Renoir. (AFP/GETTY IMAGES)

Now a federal judge in Alexandria has been appointed to decide who should keep it: the museum or Fuqua, 51, a Loudoun County driving instructor.

Fuqua did not return messages. Her attorney, T. Wayne Biggs, wrote in an e-mail to The Washington Post, “Neither my client nor I have any comment due to pending litigation.”

Fouquet, 84, also did not return phone messages, and her son, Matt Fuqua, demanded that a Post reporter stop “harassing” his family when an attempt was made to speak with her at her home in Great Falls.

Several weeks ago, someone who identified himself on the phone as Matt Fuqua raised questions about the Renoir’s origins. He told The Post in an interview that his mother had owned the Renoir “for a long time, probably 50 or 60” years. He later conferred with his sister and retracted his statement.

Musser, 61, said he moved into Fouquet’s home in the late 1970s or early 1980s. At the time, Musser said, he and his wife had separated and he needed a place to live. Musser eventually became more than just a tenant: He dated Fouquet for several years, he said. (People who remembered their relationship suggested that The Post contact Musser.) He also built Fouquet’s studio behind her home, where she held art classes for students and where she reproduced the works of famous masters, including Renoir.

She had learned much of her technique in Baltimore, where she earned a fine arts degree from Goucher College in 1952 and a master’s degree from what is now the Maryland Institute College of Art in 1957.

Until his interview with The Post, Musser said he’d been unaware of the controversy surrounding “On the Shore of the Seine.” He couldn’t describe the painting. What sticks in his mind, he said, is the artwork’s tiny size, its gold frame and its “Renoir” plaque.

Fouquet told him it was an authentic Renoir from a Baltimore museum, he said. If she said which museum, he can’t remember. Nor does he remember if she said how she’d acquired it.

“She told me it was real valuable,” Musser said. “I didn’t believe it was an original.”

Musser is not the only one who recalls seeing the Renoir.

A childhood friend of Martha Fuqua also remembers encountering the painting in Fouquet’s studio in the early 1990s. She contacted The Post in early April after reading a profile of Martha Fuqua, a former physical education teacher who filed for bankruptcy in 2009 after being laid off from her job at a District high school.

The childhood friend, who lives in the Washington area, spoke on the condition of anonymity for fear of offending Fuqua and her family.

One day, the woman said, Fuqua and Fouquet led her into the studio and showed her the painting, which was hanging upstairs.

“There was a lot of artwork on the walls, but none of it was framed, except this one,” she said. “The frame is unusual, and none of the artwork in the studio had a frame like it.”

She hasn’t forgotten its size or the “Renoir” plaque.

“I remember looking at it and saying to them, ‘Is this a real Renoir? And one of them said, ‘Yes,’ ” the woman said. “It looked like it could have been a Renoir, but I immediately dismissed it as preposterous. I didn’t ask where it came from because I just assumed they were lying.”

She added: “I remember thinking that it was too small to be a Renoir, especially if you’ve been to the National Gallery of Art and you’ve seen Renoir’s “A Girl With a Watering Can.” But the ornate frame and the plaque that said ‘Renoir’ is etched into my memory more than the content itself.”

Another family friend, Bobby J. Fontaine, recounted a similar story.

Fontaine, 54, is a Lorton artist who has several criminal convictions, including trespassing, stalking and simple assault, according to Fairfax County court records. A self-described environmental activist, he was also convicted in a Texas federal court in 2004 for sending threatening e-mails to energy executives.

He once was homeless, and Fouquet, who’d been his middle school art teacher, let him live with her, he said.

He stopped by Fouquet’s home one day in the early 1990s to borrow some canvases and paint, he said. While he was there, she took him up the studio’s stairway and flipped on the light. At the top of the stairs there was a small painting with a gold frame.

“All of her paintings on the walls didn’t have frames. But this one had a fancy frame and said, ‘Renoir.’ It had a hangover light on it,” Fontaine recalled.

He said Fouquet asked him what he thought of the piece. “She says, ‘Do you think it’s real or not?’ ” Fontaine said. “I told her, ‘I guess it’s real.’ ”

Fouquet didn’t reveal whether it was authentic, he said.

It has been more than 10 years since he has spoken with anyone in the family, he said. But in early April, after the profile of Fuqua was published, Fontaine e-mailed The Post, saying he was familiar with the painting’s history.

He also sent Fouquet and her children messages via Facebook.

“I’ve been reading about you, great story actually, although from your side of it, maybe not so much,” Fontaine wrote in early April. “[R]eally though, [it] may be [one of] the best mysteries to ever come out of Fairfax County . . . call me if you want.”

No one in the family, he said, has replied.