The Case of the Solitary Salvia

There's a mystery on my corner of Katy and the Head Gardener has demanded that I call in my best investigators.  Since Guy Noir is unavailable, I turn to you, my trusted readers, to help me solve this perplexing puzzle.

I first noticed this plant a couple of months ago, when it was a small tidy rosette of foliage hugging the ground.  The overall height of the plant, including the bloom scapes, is about 21 inches.  The foliage, however, is only 6 to 7 inches tall and there are about 4 inches of bare stem between the basal rosettes and the foliage. 

You can see that bare stem under the textured blue-green foliage, which is almost heart shaped.  Earlier today, I decided that perhaps this was actually one of the native Heartleafed Skullcaps (Scutellaria ovata or S. ovata ssp bracteata) because it's so similar in appearance to those pictured online.  But if this is Heartleaf Skullcap, then what is the plant I've been calling Heartleaf Skullcap?  That plant has lighter green leaves, a more spreading and mounding habit, and the stems are not as sturdy.  It also increases by rhizomes which send up new plants along their length, to the point I'm beginning to feel some alarm at its ability to propagate itself.  The plant pictured is not showing such an ability. 

So I'm back to thinking that this is indeed a Salvia of some sort.  Which begs the question: WHICH Salvia?  Had I kept a list over the years of the various and sundry varieties of Salvia which have come and gone here at Wit's End, I might have some chance of figuring it out.  Since my garden journal is sorely lacking in such details, I'm hoping someone will recognize this plant and provide me with its identity.