Where is “Portrait of a Lady,” a 17th-century work by the Italian painter Giuseppe Ghislandi that was looted by the Nazis in World War II?

For a brief moment this week, the answer to that 80-year-old question seemed clear: in a living room in a coastal city in Argentina.

Journalists at the Dutch newspaper Algemeen Dagblad found the painting while scrolling through an online real-estate listing, which showed it hanging above a green couch in a living room. The listing has since been taken down.

The house belonged to one of the daughters of Friedrich Kadgien, a high-ranking Nazi official who stole the painting.

The painting, which belonged to Jacques Goudstikker, a well-known Dutch-Jewish art dealer, had long been on international and Dutch lists of missing works.

On Tuesday, local prosecutors entered the house in Mar del Plata while Patricia Kadgien, one of Mr. Kadgien’s daughters, was at home.