750 LAURACEAE 15. SEXTONJA van der Werff, Novon 7: 436. 1997. 10 by Henk. van der Werff ir Cf Trees. Twigs thick, corky. Leaves alternate, clustered near the tips of the branches, pinnately veined, without domatia. Inflorescences axillary, paniculate-cy­ ai mose or racemose. Flowers bisexual. Tepals 6, erect, unequal, the outer 3 smaller than the inner 3. Stamens 9, all4-celled, the outer 6 with the cells in a shallow arc, the tr inner 3 with the cells placed in 2 pairs; filaments short, as wide as the anthers. Sta­ ai minodia 3, present. Receptacle deep, enclosing the ovary. Fruit initially covered by ill the cupule, at maturity either largely exserted or remaining enclosed in the cupule. South America; 2 species, 1 in Venezuela. ill Sextonia, previously included in Ocotea, is recognized because of its unequal R tepals, clustered leaves, profound differences in wood and bark anatomy, and differ­ N ent embryology from Ocotea species. Ct A Sextonia rubra (Mez) van der Werff, Novon 1600 m; Bolivar (Cerro Venamo, near Kava­ fa 7: 438, fig. lI-K 1997. -Ocotea rubra nayen, Ptarf-tepui, upper Rio Cuyuni). Guy­ M Mez, Jahrb. Konigl. Bot. Gart. Berlin 5: ana, Suriname, French Guiana, Brazil. 258. 1889. -Nectandra rubra (Mez) The wood is of fine quality and is used for C.K Allen, Mem. New York Bot. Gard. making furniture. Vegetatively, Sextonia ru­ N 10: 120. 1964. -Caobillo, Mana-choro­ bra resembles Mezilaurus due to its clus­ yek (Arekuna), Paci-ra-ru-yek (Arekuna). tered leaves with a rounded apex, but the Tree to 40 m tall. Montane forests, 900­ flowers and fruits are quite different. 1. 1. 2( ! 2. 3( 3. LECYTHIDACEAE 4( by Scott A. Mori and Ghillean T. Prance Small to large trees. Leaves alternate, simple, exstipulate or with minute, caducous 4. stipules, without pellucid punctations. Flowers actinomorphic or zygomorphic. Pet­ als usually free (absent or fused together in subfamilies Foetidioideae and Napoleonaeoideae). Stamens numerous, connate at base into staminal ring, the ring actinomorphic or prolonged on one side into a strap-like structure that arches over 5( summit of ovary, some apetalous species with outermost stamens modified into peta­ LECYTHIDACEAE 751 loid corona tAsteranthos brasiliensis); intrastaminal disc present or absent. Ovary inferior to half inferior. Fruits fibrous berries, dry drupes, or woody circumscissile capsules. Seeds L-many, with or without cotyledons. Pantropics; 20 genera and ca. 300 species, 8 genera and 35 species in the flora area. The Lecythidaceae, sensu lato, is a pantropical family of small to very large trees. The family includes four subfamilies, only two of which, the Napoleonaeoideae and Lecythidoideae, are found in the Neotropics. Both subfamilies are represented in the Venezuelan Guayana. The Napoleonaeoideae comprises three genera, with two genera and 11 species in West Africa and a single genus and species, Asteranthos brasiliensis, in the upper Rio Negro region of Colombia, Venezuela, and Brazil. The systematic positions of the Napoleonaeoideae and ofAsteranthos brasiliensis within the Napoleonaeoideae are currently under study, and considerable evidence is accumulating to align Asteranthos with the West African Scytopetalaceae and treat this group as a sub­ family of the Lecythidaceae (C. M. Morton, S. A. Mori, G. T. Prance, K. G. Carol, and M. W. Chase. Amer. J. Bot. 84: 530-540. 1997). The Lecythidoideae, with 10 genera and ca. 200 species, are limited to the Neotropics. Key to Genera ofLecythidaceae 1. Flowers actinomorphic 2 1. Flowers zygomorphic 4 2(1). Flowers solitary in leafaxils, petals fused into a radiate corona; fruits with persistent, annular calyx; embryo J-shaped, embedded in rumi­ nate endosperm 2. Asteranthos 2. Flowers in multi-flowered inflorescences, infrequently with a single flower, with 6-8 separate petals; fruits without persistent, annular ca­ lyx; embryo not J-shaped, without endosperm 3 3(2). Flower buds oblong, the flowers < 2.5 em diameter at anthesis; stamens < 50, the anthers dehiscing via lateral slits; ovules on lower 1/2 of sep­ tum; fruits dehiscent, the seeds freely falling from fruit; embyro with undifferentiated cotyledons 1. Allantoma 3. Flower buds globose, the flowers 5-20 em diameter at anthesis; stamens . 500-1200, the anthers dehiscing via apical pores; ovules on upper 112 of septum; fruits indehiscent, the seeds released by deliquescence of peri­ carp or by fragmentation of opercular region; embryo with plano-con­ vex, fleshy cotyledons 7. Gustauia 4(1). Inflorescences from trunk; flowers with all of hood appendages bearing anthers; fruits round, indehiscent; seeds embedded in pulp which oxi­ dizes bluish green when exposed to air 5. Couroupita 4. Inflorescences not from trunk; flowers usually with none of hood append­ ages bearing anthers, less frequently the proximal with and the distal appendages without anthers; fruits usually not round (except for B. excelsa), dehiscent; seeds not embedded in pulp 5 5(4). Buds enclosed by calyx except for horizontal slit at apex; calyx with 2 lobes at anthesis; style > 10 mm long; fruits functionally indehiscent, with 752 LECYTHIDACEAE small, inwardly falling operculum; seeds with thick, bony testa, re­ maining inside fruit at maturity 3. Bertholletia 5. Buds not enclosed by calyx; calyx with 6 lobes at anthesis; style usually < 10 mm long; fruits dehiscent, with freely falling opercula; seeds with­ out thick, bony testa, usually falling or removed from fruit at maturity .............,' 6 6(5). Androecial hood coiled inward, then with outwardly extended flap at apex of coil; fruits cylindric or campanulate; seeds with wing around circum­ ference; embryo with 2 foliaceous cotyledons 4. Couratari 6. Androecial hood flat, or if coiled inward without outwardly extended flap at apex of coil; fruits not cylindric or campanulate; seeds without wings; embryo undifferentiated 7 7(6). Androecial hood usually forming complete coil inward, with blunt-tipped appendages at apex of coil, these differentiated from more abundant, echinate hood appendages; ovary usually 2-, less frequently 4-locular; seeds usually with lateral arils, less frequently aril basal or completely surrounding testa 6. Eschweilera 7. Androecial hood flat or expanded at apex but not forming complete coil inward, the hood appendages not differentiated into blunt-tipped ap­ pendages; ovary 4-locular; seeds usually with basal arils ......... 8. Lecythis 1. ALLANTOMA Miers, Trans. Linn. Soc. London 30(2): 170, 291. 1874. Small to medium-sized trees. Leaves entire, glabrous. Inflorescences racemes or once-branched arrangements of racemes, terminal or subterminal. Flowers nearly actinomorphic, oblong, 15-22 mm long; receptacle campanulate; sepals (5)6, united at base, with triangular, small lobes at apex; petals 6, oblong; androecium urceolate, only slightly asymmetrical, the apex divided into 8-10 inwardly reflexed lacinae with anthers at apex of most of them, with additional stamens inserted sparsely over interior of androecium on short, thick, reflexed filaments, stamens ca. 30, all anthers fertile; ovary (3)4- or 5-locular, with numerous ovules in each locule; style short, with rounded, undivided stigmatic surface. Fruits woody capsules, tubu­ lar-cylindric to cylindric-campanulate, straight or slightly curved, always longer than broad, the operculum dehiscing when fruits still on tree. Seeds narrowly linear­ elongate, with poorly developed basil aril, not winged, the testa verrucose. Rio Orinoco, Rio Negro, and Rio Amazonas watersheds of Venezuela and Bra­ zil; 1 species. AIlantoma lineata (Mart. ex O. Berg) interior; fruits cylindric, much longer than Miers, Trans. Linn. Soc. London 30(2): broad; seeds with poorly developed, basal 297, t. 65, figs. 4, 5. 1874. ~ouratari ariI. Lowland forests along rivers and lineata Mart. ex O. Berg in Mart., FI. streams, 100-200 m; Amazonas (Cafio Moro­ Bras. 14(1):508,t. 7, 77. 1858.--Tabarf. coto below San Fernando del Atabapo, base Usually a canopy tree; leaves with rounded of Cerro Yapacana, Rio Autana, upper Rio to truncate bases, venation eucamptodro­ Barta, Rio Cuao, between San Carlos de Rio mous, the tertiary veins finely percurrent, Negro and Solano). Brazil (Amazonas: Rio forming 1350 angle with midrib; flowers ob­ Negro and Rio Amazonas basins).•Fig. 636. long; androecium nearly symmetric, the an­ The seeds are edible, and the bark is used thers inserted on upper margin and all over for making cigarette paper. E9L vwo1uvllV 754 LECYTHIDACEAE 2. ASTERANTHOS Desf., Mem. Mus. Hist, Nat. 6: 9, t. 3. 1820. Medium-sized trees. Leaves entire, with minute stipules, visible only on young­ est leaves. Inflorescences solitary in leafaxils. Flowers actinomorphic, 3.5-4.5 cm diameter; receptacle conical-campanulate; calyx accrescent to receptacle, radiate, circular; corolla corona-like, with 24-28 conspicuous veins from center to margin, pleated and unfolding like a parasol, the margins irregularly dentate and ciliate; fer­ tile stamens numerous, free, inserted in several rows attached in circle around base; anthers 2-locular, longitudinally dehiscent, basally attached; style erect and thin; stigma 5-8-lobed; ovary semi-inferior, 5-8-locular, with 4 ovules in each locule. Fruit an oblong-pyramidal, tardily dehiscent capsule, semi-inferior, ±2 em long, with en­ larged persistent calyx persisting around middle, the fruiting calyx coriaceous, part of fruit below calyx smooth, unribbed, 0.5 em long, part above calyx 1.5 em long, deeply 6-ribbed and tapered to pointed apex, unilocular, with single cone-shaped seed, with abundant ruminate endosperm; embryo curved on lower portion to form J-shape, with 2 small, membranous cotyledons at apex. Endemic to the Guayana Shield in Colombia, Venezuela, and Brazil; 1 species. Asteranthos brasiliensis Desf., Mem. (upper Rio Negro basin), Brazil (Amazonas: Mus. Hist, Nat. 6: 9, t. 3. 1820. upper Rio Negro basin). +Fig. 637. Tree to 25 m tall; flowers with radiate, co­ According to Bruce Nelson (personal com­ rona-like, yellow corolla; fruits with circular, munication 1986), this species descends the persistent calyx; seeds with abundant, rumi­ Rio Negro to at least Ecunaf (ca.