Originally thought Trichostema parishii, but it didn't have the long inflorescences that I've generally been seeing in pics of that species. Thanks to Charlie for the ID! It was a low but good-sized bush -- probably close to a meter high, closer to twice that wide (growth habit shot below). Unfortunately my only shots were badly overexposed, but there's one flower, in shadow, on which you can see the petal patterning.
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