Maytenus rupestris (Celastraceae), a New Species from Minas Gerais, Southeastern Brazil

Abstract

Maytenus rupestris Pirani & CarvalhoOkano, a new species of Celastraceae endemic to the Serra do Cip6, Minas Gerais, Brazil, is described and illustrated. Included in section Maytenus, it is distinct from its congeners (especially from M. boaria Molina) by its ascending, very narrow leaves with revolute margins that are entire or sparsely denticulate on the distal half, and by its few-flowered cymes. Maytenus Molina emend. Molina is one of the largest genera in the Celastraceae, with around 200 pantropical species, mostly South American (Bornstein, 1989). According to Carvalho-Okano (1992), 77 species occur in Brazil, from Amazonia to the south of the country. In the state of Minas Gerais, 14 species occur, 10 belonging to section Maytenus (M. evonymoidis Reissek, M. floribunda Reissek, M. glazioviana Loesener, M. gonoclada Martius, M. imbricata Reissek, M. ligustrina Reissek, M. radlkoferiana Loesener, M. robusta Reissek, M. salicifolia Reissek, and M. urbaniana Loesener), and 4 to section Oxyphylla Loesener (M. acanthophylla Reissek, M. aquifolia Martius, M. comocladiaeformis Reissek, and M. rigida Martius). While performing floristic surveys along the mountains of the Espinhago Range, in Minas Gerais and Bahia, a new species was found in river margins in the Serra do Cip6 and is presented here. (Note: the acronym CFSC = Colegao Flora da Serra do Cip6.) Maytenus rupestris Pirani & Carvalho-Okano, sp. nov. TYPE: Brazil. Minas Gerais: Municipio de Santana do Riacho, Serra do Cip6, Ribeirao Indequic6, Cachoeira do Corndlio, perto da Estrada da Usina, 5 Oct. 1981 (fl), A. Furlan, I. Cordeiro, M. L. Kawasaki & J. R. Pirani CFSC 7506 (holotype, SPF; isotypes, K, NY, RB, SP, VIC). Figure 1. Ab omnibus congeneribus foliis anguste oblongo-ellipticis margine revoluto integerrimo vel ultra medium remote denticulato, cymis brevibus paucifloribus differt. Shrub or small tree, 1-3 m tall, glabrous. Twigs grayish, 4-angled. Leaves alternate, ascending, narrowly oblong-elliptic, apex obtuse or sometimes acute or truncate, often mucronulate, base attenuate and decurrent to the short petiole, margin entire or rarely with 2 very small teeth on the distal part, revolute, in vivo dark green and lustrous on the adaxial face, light green and dull on the abaxial face, in sicco grayish to glaucous on both faces or slightly ochraceous on the abaxial face, 30-80 mm long, 4-8 mm wide; primary vein prominent on both faces at least toward base, venation brochidodromous, secondary veins straight to slightly curved, evident on the abaxial face, obscure on the adaxial face. Stipules 7-10 mm long, triangular, blackish. Inflorescence a reduced cyme with 2-3(-4) flowers, axillary, pedunculate, ramified, 6-14 mm long; bracts triangular, 5-7 mm long, apex acute to acuminate, margin irregularly serrulate. Flowers 5merous, short-pedicellate, cream to greenish colored; sepals ovate, ca. 1 mm long; petals free, oblong, apex rounded, ca. 3 mm long, margin thin and slightly undulate, reflexed at anthesis; stamens 5, alternate with the petals, ca. 2 mm long, filaments flattened, attenuate to the apex, broadened toward base, inserted on the base of the intrastaminal disc, reflexed at anthesis, anthers ovoid, yellow; intrastaminal disc fleshy, 5-lobed, ca. 2 mm diam., margin undulate; gynoecium of 2 fused carpels, the base of the ovary slightly fused to the disc, stigma 2-lobed on a short style. Fruit a loculicidal capsule, ellipsoid to obovoid, apiculate, ca. 10 mm long, ca. 7 mm diam., yellow to orange when ripe, opening in 2 reflexed valves consisting of 2 halves of adjoining carpels; seed 1, erect, completely surrounded by a white, soft aril. NovoN 9: 95-97. 1999. This content downloaded from 157.55.39.127 on Mon, 27 Jun 2016 06:05:15 UTC All use subject to http://about.jstor.org/terms