When I was poking around looking at Symbolist painters recently, I came across Marianne Stokes' meditative portrait of Melisande (from the Maeterlinck play Pelleas and Melisande, which Debussy adapted into an opera). Stokes was not herself a Symbolist, and
the Wikipedia article says she started out painting in a rustic naturalist vein but eventually came under the influence of the pre-Raphaelites and started painting Biblical and medieval subjects in a more stylized or ornamental manner. Not surprisingly I'm most interested in her pre-Raphaelite-influenced stuff, but even in this small selection you can see the naturalist influence in "Capri Witch" and "Faun Feeding a Squirrel".
A Capri Witch (1884-1885)
Faun Feeding a Squirrel
Melisande (1895)
Death and the Maiden (1900)
An Angel
Devaki, Mother of Krishna