"Not at all. That plant is spatulata (probably the Hartmeyer “hybrid”); ultramafica has red stipules, a very distinct and lengthy petiole, upright growth habit, and ovoid lamina."
I think a lot of people might say to simply call it D. spatulata, although that seems dissatisfying and potential bad practice in that it esrases its history. Perhaps 'D. spatulata (false D. ultramafica)' would be a good name to call it.