Panamacebus is an extinct genus of monkey known from the Early Miocene (Hemingfordian in the NALMA classification) of central Panama.

[1] Panamacebus transitus is the only and type species of this genus.

Together with Paralouatta marianae from Cuba, it is the oldest known New World monkey of North America.

[2] Fossils of Panamacebus, a left upper first molar and lower premolar,[3] were uncovered from the Las Cascadas Formation, of which tuffs were analyzed providing an age of 20.93 ± 0.17 Ma,[4] of the Panama Canal Zone.

[5]