> There is a tendency in certain areas of biology to attribute extremely minor regional variation to new species.

The article describes pretty much the opposite of this, though - the species found have no regional variation, and even overlap majorly.

If the scientists involved in the paper cited by TFA have really found a large level of genetic diversity, I don’t see the point of arguing against their definition of species. It’s not a two way street, but sufficient genetic separation is enough to establish separate species, even ones indistinguishable to human eyes.