Three new species of Manettia (Rubiaceae) are described from Panama: M. arboricola, M. microphylla, and M. longicalycina. Manettia Mutis ex L. (Rubiaceae) is a genus of herbaceous or somewhat woody, usually twining vines distributed in the West Indies, Mexico, Central America, and South America south to subtropical Argentina and Paraguay. Comprising an estimated 80-130 species, this genus was revised by Wernham (1918, 1919) and treated for Central America and Mexico in the North American Flora (Standley, 1921), Flora of Guatemala (Standley & Williams, 1975), and Flora of Panama (Dwyer, 1980). Although two papers on the classification of Manettia were published by Chung (1967, 1968), no recent comprehensive accounts of the genus exist. Traditionally, Manettia has been placed in the Cinchoneae (de Candolle, 1830; Schumann, 1889; Steyermark, 1974; Robbrecht, 1988), on account of its dry fruits with numerous ovules per locule and winged seeds. Because Manettia contains raphides, Bremekamp (1966) and Verdcourt (1958) removed it from Cinchoneae and placed it in Hedyotideae, an option also mentioned by Robbrecht (1988). In a recent cladistic study of Cinchoneae incorporating cpDNA data and other information, Andersson & Persson (1991) suggested that the presence or absence of raphides in Rubiaceae is not as important a character as previously thought. Andersson and Persson placed Manettia in Hedyotideae in the same clade as Bouvardia, Hedyotis, and Hindsia, based on shared characters of distinct placentas attached centrally by a stipe, testal outgrowth forming a concentric wing, wood having fiber tracheids and predominantly solitary vessels, and loculicidal capsules dehiscent only at the apex. During the course of preparing a treatment of Manettia for Flora Mesoamericana, three new species-all from Panama-came to light and are described below. Most interesting are the two hemiepiphytic species, M. arboricola Lorence and M. microphylla Lorence & Dwyer, which climb up tree trunks by means of adventitious roots, an unusual feature previously unreported in the genus. These species are otherwise characteristic of Manettia in terms of their flower, capsule, and seed morphology. 1. Manettia arboricola Lorence, sp. nov. TYPE: Panama. Comarca de San Bias: El Llano-Carti Road, km 16.7, 350 m, 9019'N, 78?55'W, 16 June 1985, G. de Nevers & S. Charnley 5907 (holotype, MO 3623655, photo, PTBG; isotypes, F, SCZ). Figure 1. Species non volubili hemiepiphyto habitu, radicibus adventitiis, inflorescentia terminali in ramis frondosis disposita, floribus 3-5, corolla caerulea, tubo gracili 0.50.6 mm in diametro distinguibilis. Hemiepiphytic vine ascending tree trunk, the main stem woody, 1.5-2 mm diam., the bark brownish white, peeling, adventitious roots produced at nodes, the primary branches 10-23 cm long, arising at nodes, sparsely branching again, the secondary branches 4-10 cm long, 1 mm diam., usually leafy and terminated by a single inflorescence, the internodes 1-3 mm long, each side with a longitudinal ridge flanked by 2 furrows, smooth, glabrous, whitish; leaves petiolate, the petioles 2-6 x 0.5 mm, glabrous; lamina ovate, 2.5-5 x 1-2.5 cm, the base cuneate or rounded, the apex acute, glabrous, drying dark brownish green, chartaceous or membranaceous, the 2? veins 4-6 pairs, arcuate, weakly brochidodromous; stipules narrowly deltoid, 0.5 mm long, thickened. Inflorescence terminal, glabrous, cymose, 3-5-flowered, the peduncle 10-13 mm long; flowers 4-merous, the pedicels 4-10 x 0.2-0.3 mm, bracteolate, the bracteoles subulate, 1 mm long, the hypanthium obovoid-turbinate, 1.5-2 x 1-1.2 mm, glabrous; corolla blue when fresh, salverform, the tube 8-9 mm long, 0.5-0.6 mm diam., glabrous externally and internally, the lobes narrowly lanceolate-elliptic, 7-8 x 1.5-2 mm, glabrous; stamens included, affixed 2 mm below throat, the anthers 1.5 mm long, linear-ellipsoid; style 1.5 mm long, the stigma bilobed, the lobes linear, 0.5 mm NOVON 3: 59-62. 1993. This content downloaded from 207.46.13.150 on Sat, 23 Jul 2016 05:06:44 UTC All use subject to http://about.jstor.org/terms