<i>DE MACROCARPAEAE GRISEBACH (EX GENTIANACEIS) SPECIEBUS NOVIS</i> I: AN INTRODUCTION TO THE GENUS <i>MACROCARPAEA</i> AND THREE NEW SPECIES FROM COLOMBIA, ECUADOR, AND GUYANA

A monographic revision of the neotropical genus <i>Macrocarpaea</i> (Gentianaceae: Helieae) has been initiated. The taxonomic and nomenclatural background is provided as an introduction in this first of several papers. These gentians are typically montane shrubs with large, funnelform, night-blooming, bat-pollinated flowers and have a high rate of species endemicity. It is also an excellent group from which to study neotropical montane biogeography, since they occur in all major neotropical montane habitats. Three new species are described and illustrated: <i>Macrocarpaea angelliae</i> (Ecuador) in discussion with <i>M. stenophylla</i> where a neotype is selected, <i>M. ayangannae</i> (Guyana), and <i>M. luteynii</i> (Colombia). New synonymy is reported for one published species [<i>Macrocarpaea guttifera</i> = <i>Ravenia biramosa</i> (Rutaceae)] and six “nomen herbariorum”: “Axelsonia globiflora Dusén, ined.” = <i>M. rubra</i>, “M. buchtienii Gilg, ined.” = <i>M. cinchoniifolia</i>, “M. ekmanii Ewan, ined.” = <i>M. pinetorum</i>, “M. gilgiana Rusby, ined.” = <i>M. cochabambensis</i>, “M. peduncularis Rusby, ined.” = <i>M. bangiana</i>, and “M. tabacifolia Ewan, ined.” = <i>M. cinchoniifolia</i>.