  We construct the Darboux transformation with Dihedral reduction group for the
2-dimensional generalisation of the periodic Volterra lattice. The resulting
Backlund transformation can be viewed as a nonevolutionary integrable
differential difference equation. We also find its generalised symmetry and the
Lax representation for this symmetry. Using formal diagonalisation of the
Darboux matrix we obtain local conservation laws of the system.
