Need ID expertise on Evening Primrose (Oenothera)

It seems clear that this is genus Oenothera, but which species? (subspecies?) And clearly not a pink variety, but possibly originally yellow blooms, having gained red hues.

My best guesses are O. versicolor or O. fruticosa but I can’t find literature online that helps me clearly distinguish among the 145+ species.

Bloom Color: Red-Orange (red & yellow streaked)
Petals shape: broad, curled
Stamens: ?
Pistil: yellow style & star (fork-tines) stigma
Height: ~12 in
Leaves: at base, long (6 in) slender (0.8 in), alternating veins
Sun Exposure: Full Sun
Soil: dry rocky
Bloom Time: Mid Spring (at least)
Location: In the wild near Canyon Lake in Texas (ZIP 78070)

Thanks!

That's very unique. I hope someone can positively ID it for you.

Very pretty,but I have no idea, the foliage looks like a relative of Missouri primrose,
or maybe this one
http://www.wildflower.org/plants/result.php?id_plant=OEHE3

The leaves of O. heterophylla seem to be broader. (A common name for O. fruticosa is “Narrowleaf evening primrose”.)

This message was edited May 7, 2014 12:23 PM