Cyber-Silurian

Cyber-Silurian was the name given by the Eleventh Doctor, among the alternatives Cyberlurian, Cybersilon, and Cyber-Reptilia, to a variant of Cybermen that were created through the cyber-conversion of Silurians on prehistoric Earth. They rode cyber-converted dinosaurs.

The cybercircuitry used on their dinosaurs was weak to the sonic screwdriver (COMIC: Supremacy of the Cybermen)