Some of the more interesting species (Phyta, Larians, Ledon Zoa) don't have seeds that you can put in your inventory and introduce somewhere else. Is it possible to introduce such a species to a location where it is not already present?
No, there is not. Of those three species, an area may only contain the ones provided initially.
Even if you frighten a Phyta to the "entrance" to an adjacent area, they will treat it as a wall. The same applies for Ledon Seeds.