importing cichlids in to nz ?

hey guys and girls was wanting to no if anyone could sheed some light on why we cant get the big american cichlids here in nz . such as umbees and dovii . i have talked to maf here in nz and the couldn't really help me in this mater we are aloud jags and festae here but not the two that id love to keep as family pets . any help would be a great help thanks