They can intergrade in some areas. These subspecies intergrade and are only weakly defined. The two forms gradually intergrade into each other. All these taxa do, however, intergrade with one another. "P. a. aegeria" gradually intergrade into each other. The two forms intergrade in central Costa Rica. There are two colour morphs which intergrade. Many subgroups intergrade to other soil orders. These subspecies intergrade where ranges overlap. Thus Ontario's western subspecies does not intergrade with the midland painted turtle of southeastern Ontario. However, birds from the general region of Uruguay apparently intergrade. The two subspecies intergrade where their ranges meet. Erect plants are generally mixed (and intergrade completely) with prostrate plants. They grow together in some areas and there their characteristics may intergrade. The subspecies intergrade widely in Turkey and the southern Balkans.