First of all....Cosa Nostra isn't NY mafia alone...it's a slang used by the media for all American Mafia...

Sicilian Mafia is just the Mafia of Sicily...and the strongest is called by the name of the family...like Corleone's or Genco's (...family...)

The Mafia of Napoli is called the Camorra...and they are on their way now...it's one of the oldest Mafia's but still excists...and it's still rising.

BTW The Mafia from Calabria is called the 'Ndrangheta