Vellozia stenocarpa Mello-Silva sp. nov. (Velloziaceae) is distinguished by very narrow fruits and quickly deciduous leaf blades. Morphoanatomic descriptions, illustrations, and comments on taxonomic relationships are presented. A new combination is made: Barbacenia riparia (N. L. Menezes & Mello-Silva) Mello-Silva. Three species are relegated to the synonymy of B. markgrafii SchulzeMenz, and the varieties of Vellozia marcescens L. B. Smith are merged. Distribution and morphological variation are discussed for each species. A floristic study of the Velloziaceae of Grao-Mogol, Minas Gerais, Brazil (Mello-Silva, 1989) revealed the presence of 19 species, of which four were new to science. Three of these have already been described (Mello-Silva, 1991b; Mello-Silva & Menezes, 1988); the fourth is described in the present paper. Vellozia stenocarpa Mello-Silva, sp. nov. TYPE: Brazil. Minas Gerais: Joaquim Felicio, Serra do Cabral, descida da serra, campo rupestre, 17?42'S, 44014'W, 1,000 malt., 12 Feb. 1988 (fl, fr), J. R. Pirani, W. W. Thomas, R. MelloSilva & J. B. Fernandes 2217 (holotype, SPF; isotypes, K, MBM, NY, RB, UB). Figures 1-3. Planta solitaria; caudice 8-120 cm longo. Folia trifaria; lamina mox caduca, 13-33 cm longa, 4-13 mm lata ad basim, lineari-triangulari, glabra, marginibus serrulatis, apice attenuato. Inflorescentia floribus singulis binis ternisve dispositis; pedunculo 6-15 cm longo, glabro vel apicem versus pauci-glanduloso. Flos hypanthio oblongotrigono, 10-25 mm longo, 3-6 mm diam., glabro vel pauci-glanduloso praecipue ad angulas, ad ovarium pro 4 partibus longitudinis suae adnato; tepalis violaceis, ellipticis, erecto-patentibus, 2.5-5.5 cm longis, 0.7-2 cm latis, glabris; staminibus 30, appendicibus minutis, vix laceratis, filamentis ca. 3 mm longis, antheris ca. 7 mm longis; stylo 1.6-2.5 cm longo; stigmate trilobo-peltato, ca. 3-7 mm diam. Capsula 10-25 mm longa, 4-7 mm diam., parietibus lateralibus rumpentibus dehiscens; seminibus atro-castaneis. Plant solitary; stem 8-120 cm tall. Leaves 912, spiro-tristichous, straight, erect-patent; leaf sheaths brown, brownish gray at apex, resinous; lamina 13-33 cm long, 4-13 mm broad, lineartriangular, attenuate, glabrous, soon deciduous, the margins serrate. Inflorescence with peduncles 1-3, 6-15 cm long, glabrous or with subsessile to sessile glands toward apex. Flower with hypanthium 1025 mm long, 3-6 mm diam., oblong, trigonous, glabrous or with subsessile to sessile glands on angles and, rarely, between angles; ovary filling 4/5 of the hypanthium; tepals 2.5-5.5 cm long, 0.7-2 cm broad, erect-patent, elliptic, violet, glabrous; stamens 30, the appendages inconspicuous, toothed, the filaments ca. 3 mm long, arched at base, the anthers ca. 7 mm long; style 1.6-2.5 cm long; stigma 3-7 mm diam., trilobed. Capsule 10-25 mm long, 4-7 mm diam., obovoid-oblong to oblong, trigonous, dehiscent by rupture of the lateral walls; seeds foveate, deep brown. Leaf anatomy (Hatschbach 42520, Cordeiro CFCR 4107, Pirani 2217). Blade dorsiventral. Furrows about 2/ thickness of blade. Cuticle thickened on both surfaces. Adaxial epidermis uni-biseriate, abaxial epidermis uniseriate. Stomata mostly confined to furrows. Aquiferous uni-biseriate hypodermis present on both surfaces, extending adaxially to bundle sheaths and furrows as aquiferous parenchyma. Palisade mesophyll 3-4 cell layers thick, adaxially merging with lacunar mesophyll. Fibrovascular bundles surrounded by a distinct bundle sheath, 1-3 large vessels present in each fibrovascular bundle. Phloem strands 2, separated by fibers. Fibers extending as girders, adaxially to the aquiferous parenchyma and abaxially to the hypodermis. Bundles of subepidermal sclerified cells (1-)3 cells thick present beneath the adaxial surface and 1-2 cells thick beneath the abaxial surface or at the lower edges of the furrows. Vellozia stenocarpa resembles V. angustifolia Goethart & Henrard in general aspect (although the former is more robust), in the shape and indumentum NOVON 4: 271-275. 1994. This content downloaded from 157.55.39.208 on Fri, 14 Oct 2016 04:16:45 UTC All use subject to http://about.jstor.org/terms