Would it be too presumptuous to assume that Volcanion has some sort of link to Heatran based on some very superficial shared traits?

Both are bulky quadrupeds who control fire through a secondary element (magma through molten rock/metals and steam through superheated water), and much like Heatran lives in Volcanoes Volcanion lives in inaccessible mountains.

Can we assume the gas/plasma fire guy is up next?