Skaro City Dalek

The Skaro City Daleks were the faction of Daleks who inhabited the Dalek City and were defeated by the Thals in the Thal-Dalek battle. (TV: The Daleks)

Origin
By one account, whilst the first Daleks created by Davros remained entombed beneath the Kaled Dome, the mutated survivors of the Kaled race following the neutronic war retreated to the Dalek City where they found the remnants of Davros's experiments, the vacant Mark II Travel Machines. As the now Dalek creatures came to inhabit these Travel Machines, they became the city-dwelling Daleks. (PROSE: The History of the Daleks)

Behind the scenes
The Skaro City Daleks were named in issue 19 of Doctor Who: Figurine Collection.