maybe in the 1990 they were an unique mandamento and they split into two after although i doubt it
according to the latest news there is the

sciacca mandamento with sciacca, sambuca, santa margherita and montevago families
boss salvatore di gangi (sciacca) underboss leo sutera (sambuca)

ribera mandamento with ribera, cianciana, burgio, cattolica eraclea and lucca sicula families
boss andrea montalbano (cianciana)

alessandria della rocca mandamento with alessandria della rocca, bivona and santo stefano quisquina families
boss vincenzo ferranti (bivona)