[kuhewa]

But broadly, the distribution of thermal habitat isn't very complex, it varies across a latitudinal cline and at a broad regional scale with ocean currents but your don't have small island-sized patches of warm water for example. Most fine scale anomalies are short lived especially relative to the scales speciation happens over.

Depth is a thing and can separate disparate communuties on seamounts like alpine species on mountain tops. The difference is most Maine species have a pelagic larval stage and can disperse widely, so barriers to gene flow are more limited than on land.