Notopleura (Benth. & Hook.f.) Bremek. includes about 100 species of shrubs and small trees distributed widely in the New World tropics. Notopleura plants are terrestrial or epiphytic herbs or subshrubs that are found in moist to wet tropical forests, from low to high elevations. The plants are usually fleshy to rather succulent, and the terrestrial species are often unbranched. The genus is distinguished by its stipules with glandular or laminar, often well developed appendages and its inflorescences that are terminal or often pseudoaxillary. The flowers are white, relatively small, and presumeably pollinated by insects. The carnose fruits are white, orange, red, or sometimes black, and presumeably dispersed by birds. Some Notopleura species are distylous.

Notopleura species have previously been included by most authors in Psychotria Subg. Heteropsychotria Steyerm., but recent consideration of both morphological (Taylor, 1996, 2001) and molecular (Andersson & Rova, 1999; Nepokroeff, 1997; Nepokroeff et al., 1999) characters show that this genus is better treated separately. An overview of Notopleura was presented by Taylor (2001), who presented a key to its species and recognized two subgenera. Notopleura subg. Notopleura includes the majority of species in the genus, which are terrestrial and have pseudoaxillary inflorescences; Notopleura subg. Viscagoga (Baill.) C.M. Taylor includes epiphytic species with terminal inflorescences.

When Notopleura was included in Psychotria, several published species were synonymized by most authors with Psychotria macrophylla, which was by far the most commonly collected species and considered morphologically variable and difficult to characterize. Taylor (2001, 2003) showed that Notopleura macrophylla is a clearly and much more narrowly characterizable species, and separated a number of species from it.

Author: C.M. Taylor. The content of this web page was last revised on 17 November 2010.
Taylor web page: http://www.mobot.org/MOBOT/Research/curators/taylor.shtml

Neotropics: lowland wet forest to montane forests, Mexico and the Antilles to Bolivia and Brazil.

• Nepokroeff, M., B. Bremer & K. J. Sytsma. 1999. Reorganization of the genus Psychotria and tribe Psychotreae (Rubiaceae) inferred from ITS and rbcL sequence data. Syst. Bot. 24(1): 5–27.
• Taylor, C. M. 1996. Overview of the Psychotrieae (Rubiaceae) in the Neotropics. Opera Bot. Belg. 7: 261–270.
• Taylor, C. M. 2001. Overview of the neotropical genus Notopleura (Rubiaceae: Psychotrieae), with the description of some new species. Ann. Missouri Bot. Gard. 88(3): 478–515.
• Taylor, C. M. 2003. Rubiacearum americanarum magna hama pars XV. New species and two new combinations in Notopleura (Psychotrieae) from Central and South America. Novon 13(2): 228–260.