This is the plant that sometimes gets called Ruellia squarrosa in the horticulture trade, but that name [specifically, Ruellia squarrosa (Fenzl) Cufodontis ex E. Walker] represents a later synonym for Ruellia longepetiolata (Oerst.) Hemsl., which has priority (published in 1855! ….can you believe there were people wandering around Mexico admiring Wild Petunias back then??) So many protologues, so many available names (>1,000 in Ruellia alone), so little time…but fortunately Tom Daniel clarified this one in his 2003 Flora del Bajío treatment.
I have never seen this species in the wild, but I have seen photos of it growing in its natural habitat. The photos above derive from plants in cultivation, which is probably why they look just a little bit less like a true wild type….
Cultivated (COLO Greenhouses), Tripp #397 (DUKE); Photos by Erin Tripp