Ignatius Kum Wung, a native and citizen of Cameroon, has filed a petition for review of the order of the Board of Immigration Appeals (BIA) denying his application for asylum, withholding of removal, and relief under the Convention Against Torture. The Immigration Judge found Wung to lack credibility, and Wung failed to challenge that finding in his appeal to the BIA. Wung therefore failed to exhaust his administrative remedies, and we are without jurisdiction to review this issue that is essential to the success of Wung’s claims. See Townsend v. INS, 799 F.2d 179, 181-82 (5th Cir. 1986). The petition for review is DISMISSED.