A species is defined by one simple thing: if individuals can interbreed and produce fertile offspring. There are complications related to ring species and few others, but they're not applicable here.

All human beings from all over the world can interbreed and their children will be fertile themselves (with the same rate of accidental infertility they would find in their own populations). As such, it would be completely preposterous to claim that there is more than one species of human on the planet today.