Mystery solved

WE’VE identified the “mystery blonde” who was with John Mellencamp, Matthew McConaughey and his wife, Camila Al- ves, on Monday. She’s Chris Taylor — a longtime close friend of Mellencamp’s and communications head for Ronald Perelman. We reported that the foursome was seen at jam-packed Sushi of Gari in Tribeca before heading to the Odeon. Taylor told us Mellencamp is in town debuting his new record, “Easy Target.” “We’ve always looked to artists to covey our hopes, dreams and frustrations . . . John has always been that voice and very relatable,” Taylor said. Another source told us that Mellencamp — most recently linked to Christie Brinkley — is definitely single.