Are still active? 41 year old Cosme Rivera fought as recently as March of this year despite having turned pro in 1993 at the age of 16. 69-79-2 Mexican Robert Valenzuela fights on, having a bout as recently as the end of 2017. He's currently 44 years of age and has been fighting since 1992, when he debuted at the age of 18. An easy one, but 44 year old Siarhei Khamitski just barely sneaks in, having turned pro late in 1999. Another easy one, 45 year old Lolenga Mock has been fighting since 1991, an absolutely surreal accomplishment. He's currently enjoying the greatest string of wins and success of his entire career!
A belated shout out to out of the premiere Mexican little men of this generation, Jhonny Gonzalez, whom turned pro three quarters of the way through 1999.
You'd be surprised but there are still active boxers whose debut was before Mike Tyson's and Evander Holyfield's. Like this one: http://boxrec.com/en/boxer/39140
