His death was confirmed by a spokesman for the Federal Bureau of Prisons. Mr. Scarfo had been in prison since 1988. Michael E. Riley, a lawyer for Mr. Scarfo’s son Nicky Jr. — who is himself in prison on a racketeering conviction — declined to specify a cause.
A Brooklyn-born former boxer and bookmaker nicknamed Little Nicky — he stood 5 feet 5 inches tall and weighed 135 pounds — Mr. Scarfo was known for a volatile temper and a penchant for wanton violence and vengeance as he rose to become a feared organized-crime figure. Those traits proved to be his undoing. Fearing for their lives, former associates, including his own nephew, testified against him.
“Scarfo was a mob boss for the 1980s, a greedy, ruthless despot whose family coat of arms could have been a pair of crossed .357 magnums mounted on a blood-red shield embossed with the words ‘Kill or Be Killed,’” George Anastasia wrote in “Blood and Honor: Inside the Scarfo Mob — the Mafia’s Most Violent Family” (1991).
Convicted of first-degree murder in the death of another mobster, Mr. Scarfo was described in 1989 as the first Mafia boss to be sentenced to death. (The sentence was eventually overturned, and in a second trial he was acquitted of the murder charge.)
At his death, he was serving 55 years for racketeering and participating in a criminal enterprise that sold drugs, murdered nine people, tried to kill four others and engaged in loan-sharking, extortion and gambling.
The sentence amounted to life imprisonment, since he was not scheduled for release before 2033. Sixteen of his associates were also convicted in the racketeering case.
Nicky Scarfo Jr. was sentenced to 30 years in prison for racketeering in 2015. Now 52, he had survived an assassination attempt at 24 by a gunman wearing a Batman mask.
Nicky Sr.’s eldest son, Chris, changed his surname to escape the family’s shadow, and his youngest son, Mark, died two years ago. He had fallen into a coma in 1988 after a failed attempt to hang himself.
The sons were raised in Atlantic City, where the legalization of gambling in 1976 turned out to be a windfall for what became known as the Bruno-Scarfo crime family. The family was led by Angelo Bruno from the 1950s until he was murdered in 1980.
Mr. Bruno, known as the Gentle Don or the Docile Don, was succeeded briefly by Philip Testa, who was called Chicken Man, apparently because of his links to the poultry business. Mr. Testa was soon killed by a nail bomb.
Succeeding Mr. Testa, Mr. Scarfo muscled in on the casino boom through his company, Scarf Inc., pouring concrete for the foundations of several gambling palaces, including one that opened as Harrah’s Trump Plaza. In obtaining contracts, he capitalized on his close association with leaders of Local 54 of the Hotel and Restaurant Employees and Bartenders International Union.
The New Jersey Commission of Investigation concluded in 1989 that through those ties “the Scarfo family funneled bribes and engaged in other corrupt deals” with Mayor Michael J. Matthews, who pleaded guilty to extortion in 1984 and was sentenced to federal prison.
Nicodemo Domenico Scarfo was born in Brooklyn on March 8, 1929, to an Italian immigrant family from Naples and Calabria. His nephew, Philip Leonetti, later wrote that the family “had strong ties to the Mafia in Italy.”
His father was Philip Scarfo, a laborer who worked at an Atlantic City hotel and who, according to Mr. Leonetti, “was 100 percent legit.” His mother was the former Catherine Piccolo. The family moved from Brooklyn to New Jersey when he was 12.
In addition to his two sons, Mr. Scarfo is survived by his second wife, Domenica, Mr. Riley said.
Mr. Scarfo nurtured his reputation early. His high school yearbook said he was out to “lick the world.” After graduating, he became a notoriously volatile amateur boxer before apprenticing himself to three mob-connected uncles in Philadelphia.
After stabbing a longshoreman to death in a bar, Mr. Scarfo was convicted of manslaughter and served six months. Mr. Bruno exiled him to Atlantic City, where he was later charged, in a federal racketeering case, in connection with the murder of an uncooperative local judge. The judge had been killed execution-style in a restaurant as he dined with his wife.
Mr. Scarfo was also imprisoned for refusing to testify before a state crime commission and, in another instance, for illegal gun possession.
If, as Mr. Anastasia suggested, the Scarfo family’s credo was “kill or be killed,” Mr. Scarfo’s management style was grounded in greed (he imposed a tax on even petty criminals operating within his turf) and paranoia (even an unwitting sneer could provoke him to take violent revenge).
In 1985, Mr. Scarfo assigned a hit man, Nicholas Caramandi, to extort $1 million from Willard Rouse III, a developer who was seeking to build on the Delaware River waterfront. Mr. Rouse immediately informed the Federal Bureau of Investigation.
Indicted in the scheme, Mr. Caramandi turned state’s evidence. So did Mr. Leonetti, Mr. Scarfo’s nephew and now an author, who was the family’s second in command at the time and was known as Crazy Phil. He is now a federally protected witness.
Even in prison, Mr. Scarfo remained an unreconstructed criminal into his 80s, prosecutors say. As recently as 2011, he was named in a companion indictment to the extortion of a financial group based in Texas that led to his son Nicky Jr.’s conviction in 2015.
The elder Mr. Scarfo idolized Al Capone, a fellow transplanted Brooklynite, but hardly resembled him. Where Capone had wit and panache, Mr. Scarfo had neither. Capone supposedly said, “You can go a long way with a smile; you can go a lot farther with a smile and a gun.” Mr. Scarfo preferred just the gun.
“There was no sense of charisma; not even a hint of the old Mafia mystique,” Mr. Anastasia wrote. “Scarfo was a bully with a gun.”