maybe thats the case in central america, but theres a big diversity of phenotypes in the countries of south america that received more immigration. i live in northeastern brazil (the region that rececived the least amount of immigrants) and i see a very diverse amount of phenotypes everyday. from nordic looking to middle-eastern (probably converso descent) to niggers and your typical mestizos. purebred niggers are provably the rarest ones, since the state i live in didnt have a lot of plantations and didnt import a lot of slaves. most of the population is some flavor of portuguese-native mixture.
Brazil