Exostema valenzuelae was not validly published. It was listed by A. Richard in a note under Exostema parviflorum in his treatment of the Rubiaceae of Cuba. This note said that he had used the "bad" name Exostema valenzuelae incorrectly for this species, with this "bad" name used on the illustration of this species in that work. The name Exostema valenzuelae was subsequently catalogued by Index Kewensis, perhaps based on the figure. Richard's figure alone could be adequate to validate the publication of this name, except for the clear statement by Richard that he did not accept this name in this work. Later Urban found Richard's "bad" name, again perhaps on the figure, and he adopted it and cited it as an older name for its species. Urban cited two other, actually older, validly published names in synonymy there with Exostema valenzuelae, so while Urban did publish this as a valid name it was superflous and illegitimate. The variety names published under Exostema valenzuelae can be attributed to Urban's name, so they are valid but not correct, and cannot be used until they are transferred to another species. See the species page for Solenandra ixoroides for more details.