  It is well known that the Kerr-NUT-AdS-dS black hole admits two linearly
independent Killing vectors and possesses a hidden symmetry generated by a
rank-2 Killing tensor. The near-horizon geometry of an extremal Kerr-NUT-AdS-dS
black hole admits four linearly independent Killing vectors, and we show how
the hidden symmetry of the black hole itself is carried over by means of a
modified Killing-Yano potential which is given explicitly. We demonstrate that
the corresponding Killing tensor of the near-horizon geometry is reducible as
it can be expressed in terms of the Casimir operators formed by the four
Killing vectors.
