OK, forgive the quality of the photograph of what is admittedly one of the most common species in the genus (trust there is a back story associated with this, and move on….), but here it is: Ruellia macrophylla. One of the most easy to recognize species in the Neotropics because…. I said so? Look for the long pedunculate inflorescences that boast big, gaudy, and floppy red flowers. You will find this species clambering against steep slopes that line the highways in northern Colombia and Venezuela. Its leaves aren’t exceptionally large, as implied by the specific epithet, but if you need further confirmation, keep it company until it sets seed, then look for hygroscopic margins restricted to the margins of said seeds. Or just ask a taxonomist.
Ruellia macrophylla is widespread in northern South America, very much unlike its nearest relative, Ruellia lutea (aka, Ruellia macrophylla var. lutea until Manuel and I raised this taxon to the rank of species in our monograph of Venezuelan Ruellia). In contrast, Ruellia lutea grows only in the narrowest stretch of northern Venezuela where it occurs sympatrically with, and flowers contemporaneously with, Ruellia macrophylla. Because no hybrids between the two have ever been seen and thus these two entities appear to be reproductively isolated, I feel quite comfortable with the decision to recognize them as separate species.
Anyway, I digress. Take a trip to Parque Nacional Henri Pittier (Venezuela) or Parque Nacional Tayrona (Colombia) and marvel at a few million years of evolutionary history that ‘built’ Ruellia macrophylla. Natural selection, we love you.
Wild Collected, Colombia, Tripp & Luján #490 (RSA) and Tripp et al. #5174 (COLO); Photos by E. Tripp & N. Medina