I know that I’ve said all the other species in this genus are highly distinctive, but if any stands worthy of the uber designation, it is Ruellia jussieuoides.
First: Ruellia jussieuoides loves high quality, wet rainforest habitats. Second: as visible even from the photo, the secondary venation is raised above the plane of the leaf. Third: floral tubes of R. jussieuoides are extremely long and thin, and the orifice / opening is equally as narrow – all indicative of adaptation to butterfly pollination.
I first saw this species at a rather magical swimming hole in Chiapas (Cascadas de Agua Azul) with Kyle, on the first of many wonderful international trips we’ve taken together. In retrospect, I’m still not sure whether the plant or the neon blue swimming hole was more enchanting. But at any rate, it is also among the first few Neotropical Ruellia that I saw in the field.
Turns out this species is almost certainly synonymous with Ruellia puri from South America. A sweet little geographic disjunction going…read about it in Tripp & McDade 2012 (Brittonia). Ruellia jussieuoides has a neat geographic disjunction between Central America and central / western South America… bypassing northern South America. See paper cited above for more info.
Big thanks to our colleague Alexander for sharing photos of this plant with us. Helped to convince me that the two names were indeed representative of the same biological species.
Wild collected, Mexico, Tripp & Dexter #156 (DUKE); Photo 1 by Erin Tripp
Not vouchered, Bolivia; Photo 2 by Alexander Schmidt-Lebuhn