Rubiacearum Americanarum Magna Hama Pars XXIV: New Species of Central and South American Bouvardia, Hillia, Joosia, Ladenbergia, Pentagonia, and Posoqueria

Abstract

Recent Neotropical exploration and floristic studies have continued the discovery of species of Rubiaceae new to science, including the six species described here: Bouvardia costaricensis C. M. Taylor of central Costa Rica is distinguished by its foliaceous enlarged calyx lobes and long white salverform corollas; Hillia pumila C. M. Taylor of dwarf montane forests in central Peru is distinguished by its quite small leaves and stipules; Joosia antioquiana C. M. Taylor of northwestern Colombia is distinguished by its long stipules, leaves with numerous secondary veins, and four entire (i.e., unornamented) corolla lobes; Ladenbergia franciscana C. M. Taylor of southern Ecuador is distinguished by its calyptrate stipules, small, mostly obtuse leaves, and shallowly lobed calyx limb; Pentagonia osaensis C. M. Taylor of southern Costa Rica is distinguished by its dense pilosulose to velutinous pubescence and its subtruncate to very shallowly lobed calyx limb; and Posoqueria laevis C. M. Taylor of Panama is distinguished by its leaves with the secondary and higher-order venation not visible.