Ecosystems on isolated islands, full of endemics, are vulnerable to invasions of widespread species (https://en.wikipedia.org/wiki/Lyall's_wren) and there are probably many examples of such a phenomenon. I was curious if you know any examples of the opposite. A local species, endemic to an island or archipelago that has spread to the continent??
The harvest spider Dicranopalpus larvatus seems to be doing that.