Taxonomic study of Myrtaceae in forest fragments in Amazonian Maranhão, Brazil Author Amorim, Gabriela Dos Santos Programa de Pós-graduação em Biologia Vegetal, Universidade Federal de Pernambuco, Av. Prof. Moraes Rego, 1235 - Cidade Universitária, 50670 - 901, Recife - PE, Brazil. Author Barbosa, Maria Regina De Vasconcellos Departamento de Sistemática e Ecologia, Universidade Federal da Paraíba, Cidade Universitária, Caixa Postal 5065, 58051 - 970, João Pessoa- PB, Brazil. Author Jr, Eduardo Bezerra De Almeida Departamento de Biologia, Universidade Federal do Maranhão, Cidade Universitária Dom Delgado, Av. dos Portugueses, 1966 - Vila Bacanga, 65080 - 805, São Luís - MA. Author Thomas, William Wayt 0000-0002-4996-536X Institute of Systematic Botany, New York Botanical Garden, 2900 Southern Boulevard, Bronx, 10458 - 5126, NY, United States. wthomas @ nybg. org; https: // orcid. org / 0000 - 0002 - 4996 - 536 X wthomas@nybg.org text Phytotaxa 2022 2022-10-11 568 1 27 60 http://dx.doi.org/10.11646/phytotaxa.568.1.3 journal article 10.11646/phytotaxa.568.1.3 87ddb879-1616-4e3b-8817-434b61fb0c60 1179-3163 7184245 18. Myrcia amazonica De Candolle (1828: 250) . Type:— BRAZIL . Amazonas : Solimoes , s.d., C.F.P. Martius s.n . ( lectotype designated by McVaugh 1969 [p. 110]: M). ( Fig. 5A .) Tree or shrubs 2– 10 m . Twigs glabrous or sparsely pubescent, the indumentum brownish, the branches and inflorescence reddish. Leaves with petioles 2–4 mm long, pubescent, channeled; blades elliptic, lanceolate or ovate, 3.7–6.7 × 1.9–3.2 cm , glabrous, chartaceous, discolorous; glands conspicuous adaxially and strongly marked; base cuneate or rounded; apex acute or acuminate, rarely cuspidate; midvein adaxially impressed of flat; lateral veins visible, not arched, 8 to 12 pairs; intra-marginal vein 1–2 mm from the margin, margin flat. Inflorescence terminal or subterminal, panicle, pyramidal, flowers lax, the axis 7.8–13.8 cm long, glabrous, the first branching 4.2–6.8 cm long; bracts linear, ca. 2 mm , caducous before anthesis, pubescent; pedicels 1–3 mm long or absent, sparsely pubescent; bracteoles lanceolate or linear, 0.7–2 × 0.2 mm , caducous before anthesis, glabrous or sparsely pubescent; flower buds obovate, 2 x 1.5 mm , not constricted above ovary; calyx-lobes free, five, orbicular, 0.5 × 1 mm , glabrous, not reflexed, persistent in the fruit; ovary 2–locular. Immature fruit globose, 0.5 cm diameter, glabrous, surface smooth. FIGURE 5. A. Fruits in Myrcia amazonica . B. Flowers in Myrcia bracteata . C–D. Flowers and fruits in Myrcia cuprea . E–F. Flowers and immature fruits in M . eximia . G–H. Flowers in Myrcia guianensis . I–J. Flowers bud and immature fruits in Myrcia multiflora . K–L. Flowers bud and immature fruits in Myrcia selloi . M–N. Flowers and fruits in Myrcia splendens . O. Flowers in Myrciaria tenella . P. Fruit in Psidium guineense . Note:— Myrcia amazonica may be recognized by its reddish branchlets and inflorescence, and its pyramidal panicle with small lax buds. This species is morphologically similar to M . guianensis from which it is distinguished by its reddish branches and inflorescences (vs. grayish), leaves with an adaxially impressed or flat midvein (vs. prominent) and 2-locular ovary (vs. 3-locular). Distribution and habitat:— Known from south Central America, Bolivia , Brazil , French Guiana , Suriname and Venezuela . In Brazil it is widely distributed (POWO 2020, Flora do Brasil 2020 ). In Amazonian Maranhão , M . amazonica was found growing in “terra firme” and secondary forests. Phenology:— Flowering from May to August and fruiting in August. Specimens examined:— BRAZIL . Maranhão : São José de Ribamar , Sítio Aguahy , 2°38’51” S , 44°08’04” W , 28 August 2017 (fr.), G.S. Amorim 374 ( MAR !) . São Luís , Granja Barreto , 2°31’47” S , 44°18’10” W , 12 May 1950 (fl.), R.L. Fróes 24260 ( IAN !) ; Reserva Florestal do Sacavem [Mata da Caema], 2°34’04” S , 44°15’44” W , 1958 (fl.), J. Ferreira et al. 58 ( MAR !) ; 2°31’47” S , 44°18’10” W , 01 July 1992 (fl.), G.M. Barroso 61 (UEC, image); 27 May 1992 (fl.), F.H. Muniz 103 (RB, image); 2°30’ S , 44°15’ W , 14 August 1992 (fl.), F.H. Muniz 26 (INPA, image); 2°30’ S , 44°15’ W , 26 June 1993 (fl.), F.H. Muniz 392 (INPA, image); 2°31’47” S , 44°18’10” W , 28 June 1993 (fl.), F.H. Muniz 378 (INPA, image) . Turiaçu , 1°39’48” S , 45°22’18” W , Fazenda Vila Palmares , 23 July 1977 (fl.), A.E. Silva 131 ( PEUFR !) . Additional specimens examined:— BRAZIL . Amazonas : Manaus , Igarapé do Passarinho , 2°57’ S , 60°02’50” W , 21 August 1956 (fl.), D.F. Coêlho INPA4109 (INPA, image). Pará: Santarém, Comunidade São Brás, 2°30’46” S , 54°51’33” W , 12 October 2012 (fl.), V.Y.P. Calao s.n. (INPA, image). Rondônia : Porto Velho, Jaci-Paraná, 8°45’43” S , 63°54’14” W , 13 July 2008 (fl.), G . Pereira-Silva 13547 (RON, image); Fragmento de floresta próximo a margem direita do, Floresta estacional semidecidual com relevo plano e afloramento rochoso, 9°16’19” S , 64°23’37” W , 26 June 2012 (fl.), M.F. Simon 1557 (RON, image) .