Merianthera calyptrata sp. nov. (Melastomataceae, Myrtales), a new candelabriform species from Minas Gerais, Brazil Author Goldenberg, Renato Universidade Federal do Paraná, Departamento de Botânica, Caixa Postal 19031, 81531 - 970, Curitiba, Paraná, Brazil. rgolden@ufpr.br Author Bochorny, Thuane Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Rua Pacheco Leão 915, 22460 - 030, Rio de Janeiro, Rio de Janeiro, Brazil. tbochorny@gmail.com Author Amorim, André Márcio Universidade Estadual de Santa Cruz, Departamento de Ciências Biológicas, Km 16 Rodovia Ilhéus-Itabuna s / n, 45662 - 900, Ilhéus, Bahia, Brazil. amorim.uesc@gmail.com Author Ziemmer, Juliana Klostermann Universidade Estadual de Campinas, Programa de Pós-Graduação em Biologia Vegetal, Instituto de Biologia, Rua Monteiro Lobato 255, 13083 - 862, Cidade Universitária Zeferino Vaz, Campinas, São Paulo, Brazil. juliana.ziemmer@gmail.com Author Fraga, Claudio Nicoletti de Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Rua Pacheco Leão 915, 22460 - 030, Rio de Janeiro, Rio de Janeiro, Brazil. cnfraga@jbrj.gov.br text European Journal of Taxonomy 2023 2023-08-09 888 64 76 http://dx.doi.org/10.5852/ejt.2023.888.2209 journal article 54789 10.5852/ejt.2023.888.2209 edb239bf-d47f-4b58-9f51-38db83e2fb22 2118-9773 8246697 Genus Merianthera Kuhlm. Arquivos do Instituto de Biologia Vegetal do Rio do Janeiro 1 (3): 231–233 ( Kuhlmann 1935 ) , here amended . Type species Merianthera pulchra Kuhlm., Arquivos do Instituto de Biologia Vegetal do Rio do Janeiro 1 (3): 231–233 ( Kuhlmann 1935 ) . Description (modified from Goldenberg et al. 2012 ) Shrubs to treelets, sparsely to moderately glandulose-granulose. Leaves opposite, entire, acrodromous, caducous. Inflorescences terminal short panicles, depauperate few-flowered cymes or reduced to solitary flowers; bracts absent, bracteoles absent or small, caducous. Flowers pedicellate, 5(–6)-merous; hypanthium sometimes with a constriction above the ovary; calyx regularly or irregularly lobed, seldom calyptrate and dehiscing through a transversal, circumscissile slit; petals free, obovate to elliptic; stamens 10(–12), glabrous, strongly zygomorphic and dimorphic, filament strongly flattened, connective with one basal (descending) and one apical, erect (ascending) portion, ascending portion always 2-lobed, lobes curved backwards in the antesepalous stamens and not curved backwards in the antepetalous stamens, anthers slightly dorsally arched, with a dorsal or apical pore in the antepetalous stamens and an apical to slightly ventrally located pore in the antesepalous stamens. Ovary completely inferior, with a sterile, apical stylar column, (3–)4–5-celled, the protruding placentae axillary; style curved at the apex, glabrous or puberulous, stigma punctiform. Fruits costate, apically constricted or not, rupturing along the costae when mature or seldom through (3–)4 regular, longitudinal slits; seeds many, pyramidal, testa rugulose. Key to the species of Merianthera (modified from Goldenberg et al. 2012 ) 1. Stems hollow, fistulose when dry; flowers solitary, either on top of a short peduncle (then a 1-flowered strongly reduced cyme) or not .......................................................................................................... 2 – Stems solid when dry; flowers in panicles or seldom in depauperate cymes with two or more flowers ............................................................................................................................................... 3 2. Leaves with an acuminate to abruptly acuminate apex; flowers bibracteolate, borne on a short peduncle; calyx not calyptrate, dehiscing through regular lobes ................ M. burlemarxii Wurdack – Leaves with a rounded or obtuse apex; flowers ebracteolate, not borne on a peduncle; calyx calyptrate, dehiscing through a transversal, circumscissile slit ............................................................................ ...................................................................... M. calyptrata R.Goldenb., Bochorny & Fraga sp. nov. 3. Calyx regularly lobed; style basally puberulous or granulose-glandulose ....................................... 4 – Calyx irregularly lobed; style glabrous ............................................................................................. 7 4. Leaves glabrous on abaxial surface; petals purple ........................................................................... 5 – Leaves with dense indumentum on abaxial surface; petals pink ...................................................... 6 5. Hypanthium weakly costate and smooth; calyx lobes lacking external teeth; style glandular-puberulous on its basal half ........................................................... M. bullata R.Goldenb., Fraga & A.P.Fontana – Hypanthium strongly costate and rugose; calyx lobes with distinct, thick external teeth; style granulose-glandulose at the base ............................................. M. verrucosa R.Goldenb., Fraga & A.P.Fontana 6. Leaves with strigulose abaxial surface, with curled, discrete trichomes ............................................ .............................................................................................................. M. sipolisii (Cogn.) Wurdack – Leaves with lanate abaxial surface, with arachnoid-amorphous, matted trichomes ........................... ......................................................................................................... M. eburnea R.Goldenb. & Fraga 7. Leaves with petioles 12–29 mm long; panicles with more than 8 flowers .......... M. pulchra Kuhlm. – Leaves sessile or with petioles up to 9 mm long; depauperate racemes with up to 4(–5) flowers, reduced to triads, diads or sometimes single flowers .......................................................................... ................................................................................ M. parvifolia R.Goldenb., Fraga & A.P.Fontana