Based on new finds of mandibular tooth plates of the chimaeroid Stoilodon aenigma Nessov &Averianov, 1996 (Holocephali, Chimaeroidei) from the Lower Cretaceous of central Russia, the diagnosis of the genus is modified and validity of the taxon is confirmed. New record of mandibular plate of the species from the Ryazanian regional stage (boreal Berriasian stage) of the Moscow Region has allowed us to expand stratigraphical distribution of the species within the whole early Cretaceous.
