Score BIG TIME. Sort of like shooting the moon if you are playing Hearts, but way bigger. Ruellia eurycodon is one of two bat-adapted species of Ruellia that we encountered on our August 2016 fieldtrip (check out the other before you close your web browser: Ruellia verbasciformis). Ruellia eurycodon will be remembered affectionately for many reasons, only one of which was the extremely sweet floral fragrances that flowers produce. Floral fragrance is essentially unknown among all Neotropical Acanthaceae (some OW members of the family are fragrant). Why the exception in this case? How are Acanths as a whole so “successful” without fragrance? Better to back up and ask, what is the relationship between fragrance and fitness, summed across all angiosperms? Is the production of fragrance, widely regarded as a crucial component of a suite of reproductive characters, driven by ecology or limited by historical constraints and an inept underlying genomic architecture? Are Acanths somehow fragrant in a way we have failed to detect in this 21st Century? All questions unanswered, all ready for an enterprising student. Be the one.
Alas, is it perfume from a dress, that makes me so digress?
Ruellia eurycodon is a small tree to ~3m with dull yellow flowers that open at night. We found the species abundantly flowering and fruiting in an intact semi-evergreen forest that comprises Reserva Natural Vagafogo, not far from Pirenópolis. The very kind family-owner of this reserve welcomed us into his property, assured us we would find the species (he was right!), then fed us coffee. Ruellia eurycodon is related to R. exserta and R. steyermarkii–both bat pollinated (the former from Brazil, the latter from Venezuela) as well as several red-flowered species including Ruellia inflata.
Wild collected, Brazil, Erin Tripp #5942, w/ Nico Medina, Cíntia Kameyama (COLO); Photos by Erin Tripp, Cíntia Kameyama