Contributions to South American Caesalpiniaceae. I. Two New Species of Jacqueshuberia from the Venezuelan Guayana Basil Stergios BioCentro, UNELLEZ, Mesa de Cavacas, Edo. Portuguesa 3323, Venezuela Paul E. Berry Missouri Botanical Garden, P.0. Box 299, St. Louis, Missouri 63166, U.S.A. ABSTRACT. Study of Caesalpiniaceae collections fromtheVenezuelanGuayanahasrevealedthefirst knownoccurrencesofJacqueshuberiaintheregion, with two new species, J. splendens from Cerro Ar- acamuni in southern Amazonas state and J. pustu- lata from the Rfo Autana watershed in northern Amazonas state. Resumen. El estudio de colecciones de Caesal¬ piniaceae de la Guayana venezolana ha resultado en el primer reporte del genero J acqueshuberia de la region, con dos especies nuevas, J. splendens de Cerro Aracamuni, al sur del Estado Amazonas, y J. pustulata de la cuenca del rfo Autana al norte del Estado Amazonas. The most recently described of the five previ¬ ously known species of Jacqueshuberia, J. brevipes Bameby (1990), was described from Guyana and was the first report of this genus outside of the Am¬ azon basin (Silva & Graham, 1980). Due to Vene¬ zuela’s proximity to Guyana, it was to be expected thatthegenuswouldeventuallybefoundthere.The highly restricted distributions of all known species in the genus, as well as the paucity of collections, were well summarized by Bameby (1990), as was the genus’s botanical history since it was first de¬ scribed by Ducke (1922) from Brazilian Amazonia. Both new species described herein are known fromsinglecollectionsfromAmazonasstateinVen¬ ezuela. Jacqueshuberia splendens is presently known from rocky slopes of Cerro Aracamuni at 800 m elevation in southern Amazonas state, whereas J. pustulata is restricted to northern Ama¬ zonas in the headwaters of Autana River at 110- 120 m elevation. Both species share a low growth habit(4—5m)andlocaldistributionsamongshrub¬ byorpatchy,low,streamsideforests. Jacqueshuberia pustulata Stergios & P. E. Berry, sp. nov. TYPE: Venezuela. Amazonas: Muni- cipioAtures,cafioCabezadeManteco,afluen- te del rfo Autana en Salto Manteco, 5°52'N, 67°27'W, 110-120 m, 10 Nov. 1984, E. Mel- gueiro & F. Gudnchez 5 (holotype, TFAV; iso¬ types, MO, PORT). Figure 1. Arbor 5-metralis, foliis 35-40 cm longis, 24—28-pin- natis; pinnis 50-70-jugatis, rachi angulato, lateraliter acu- to, intemodiis dense paleaeeo-pubescentibus; foliolis ru¬ gose reticulatis, supra distincte pustulatis, 10—11 mm longis, 1—2 mm latis; calycis tubo viridi-olivaceo, petalis cucullatis luteis, 6 mm longis, 3 mm latis. Small tree up to 5 m tall; branchlets notably 5-sulcate, 8-10 mm thick, reddish brown tomen- tulose alongthe roundedridges but nearly glabrous within the grooves. Stipules paripinnate, coppery paleaceous-tomentulose along midrib, 2.5-3 cm long with 16-20 pairs of leaflet-like lobes; stipule lobeslinear-lanceolate,somewhatcymbiform,8-9 X 1-1.2 mm, minutely appressed-pilulose, es¬ pecially near the base, midrib and 6-8 pairs of straight-ascending lateral nerves distinctly raised on both surfaces, lateral nerve pairs becoming somewhat subcontiguous towardthe apex. Leaf 35- 40 cm long, 3.5-4 mm thick along lower half, at¬ tenuating toward the apex, stalk minute-pilulose; rachis adaxially canaliculate and angled with a pointed ridge along the entire length; petiole 4-4.5 cm; interpinnal segments 0.8 cm, densely palea¬ ceous-tomentulose along lateral ridge extending fromthepinnalnodes;pinnae24—28-paired,pairs remaining opposite along entire leaf length, 7—10 cm long, the shorter pinnae occurring toward the base and apex of the leaf, interfoliate segments 1 mm; leaflets 50-70-jugate, opposite along rachis, 10-11 X 1-2 mm, somewhat falcate-naviculiform with a rounded apex, inequilateral and generally applanateat thebase, glabrous, stiff-herbaceousin texture,rugose-reticulateonbothsurfacesbutpri¬ marily on the lower and notably pustulate on the upper, midvein readily visible on lower surface but Novon 6: 429-433. 1996.