The band's hits include Dude Looks Like A Lady and Cryin'
Aerosmith singer Steven Tyler has ended speculation that he is leaving the band by joining guitarist Joe Perry on stage in New York's Irving Plaza.
"I just want New York to know, I am not leaving Aerosmith," Tyler declared, before launching into the group's signature hit, Walk This Way.
The surprise reunion came during a gig by Perry's solo project.
Last week, the guitarist said he had not spoken to Tyler for months and the group were looking for a new frontman.
Speaking to the Las Vegas Sun newspaper, he said: "Steven quit as far as I can tell," apparently gleaning the information from a magazine interview in which Tyler said he wanted to pursue his own solo career.
Perry went into more detail on the pair's estrangement on the micro-blogging site Twitter over the weekend.
"Last time I phoned him he hung up on me," he wrote.
"In the meantime Aerosmith is positivly [sic] looking for a new singer to work with," he added.
"You just can't take 40 years of experience and throw it in the bin!"
The guitarist also revealed that, for several months, Tyler had travelled separately to the rest of the band, kept a private dressing room, and would only see them on stage.
A video of the pair's New York reunion gave little clue as to whether they had patched up their relationship.
Before they launched into Walk This Way, Tyler appeared to make a dig at his bandmate of 40 years.
"You are a man of many colours," he pronounced. "But I am the rainbow!"