Four new species of Trembleya (Melastomataceae: Microlicieae) from Serra do Cabral, Minas Gerais, Brazil

Four new species of Trembleya (Melastomataceae: Microlicieae) from Serra do Cabral, Minas Gerais, Brazil KARINA FIDANZA1, ANGELA BORGES MARTINS2,

AND

FRANK ALMEDA3

1

Programa de Pós-Graduação em Biologia Vegetal, Departamento de Biologia Vegetal, Universidade Estadual de Campinas, Campinas, São Paulo, P. O. Box 6109, 13083-970, Brazil; e-mail: karina.fi[email protected] 2 Departamento de Biologia Vegetal, Universidade Estadual de Campinas, Campinas, São Paulo, P. O. Box 6109, 13083-970, Brazil; e-mail: [email protected] 3 Department of Botany, California Academy of Sciences, 55 Music Concourse Drive, Golden Gate Park, San Francisco, California 94118, USA; e-mail: [email protected]

Abstract. Nine species of the Brazilian endemic genus, Trembleya, were collected during a floristic survey of the tribe Microlicieae on Serra do Cabral, an isolated mountain range in north-central Minas Gerais State, Brazil. Four of these are newly described and illustrated here: Trembleya inversa, T. purpurascens, T. rubra, and T. serrulata, represent new taxa for the genus. These new species appear to be endemic to Serra do Cabral where they occur in campo rupestre and cerrado vegetation. Serra do Cabral has the distinction of harboring more species of Trembleya than any other mountain range in Brazil. Key Words: Endemism, Brazil, Serra do Cabral, Melastomataceae, Microlicieae, Trembleya. Resumo. Nove espécies do gênero brasileiro Trembleya foram coletadas durante um levantamento florístico da tribo Microlicieae na Serra do Cabral, uma cadeia isolada de montanhas no centro-norte do estado de Minas Gerais, Brasil. Quatro delas, que representam novos táxons para o gênero, são aqui descritas e ilustradas pela primeira vez: Trembleya inversa, T. purpurascens, T. rubra, e T. serrulata. Estas novas espécies parecem ser endêmicas da Serra do Cabral onde ocorrem no campo rupestre e cerrado. A Serra do Cabral distingue-se por abrigar mais espécies de Trembleya do que qualquer outra cadeia de montanhas no Brasil.

The family Melastomataceae, variously reported to comprise 166–179 genera and 4500–5150 species, are distributed within the tropical and subtropical regions of the world (Claussing & Renner, 2001; Almeda, 2003; Mabberley, 2008). Most representatives of this family (ca. 3000 species) are concentrated in South America, with Brazil having the greatest number of species (1326) and 68 genera (Goldenberg et al., 2012). The Melastomataceae are widely distributed in Brazil, occurring from Amazonas in the North to Rio Grande do Sul in the South. They are a common element in many of Brazil’s vegetational formations. Several

genera and species of Melastomataceae are restricted to limited areas within the cerrado, Brazil’s second largest biome and one of its two biodiversity hotspots (Mittermeier et al., 2004). Many species are known only from isolated mountain tops in Bahia, Goiás, and Minas Gerais states. Trembleya DC., one of six genera now assigned to the tribe Microlicieae (Almeda & Martins, 2001; Fritsch et al., 2004), comprises 23 species. All species of Trembleya are endemic to southeastern Brazil with most (almost 90 %) occurring in “campo rupestre” along the Espinhaço Range in Minas Gerais. Only Trembleya parviflora (D. Don) Cogn.

Brittonia 65(3): 280Y291 (2013), DOI 10.1007/s12228-012-9281-x ISSN: 0007-196X (print) ISSN: 1938-436X (electronic) © 2013, by The New York Botanical Garden Press, Bronx, NY 10458-5126 U.S.A. Published online: 9 July 2013

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and Trembleya phlogiformis DC., are geographically widespread. All species of Trembleya are shrubs and subshrubs, rarely small trees, with prevailingly 5- merous (rarely 4- or 6- merous) flowers, superior ovaries that are 3–5-locular, capsular fruits with apical dehiscence, and a deciduous central columella (Almeda & Martins, 2001). Among the genera of Microlicieae, Trembleya is most closely related to Microlicia D. Don and Lavoisiera DC. The differences between Microlicia and Trembleya were established by Candolle (1828), reviewed by Martins (1997), and more recently evaluated and summarized by Almeda and Martins (2001). According to these latter authors, the species of Microlicia have solitary, ebracteolate flowers, and leaves and internodes that are of uniform length (from base to apex) on both vegetative and flowering branches. Species of Trembleya have flowers in simple or compound bracteate dichasia and/or reduced to isolated flowers, and the leaves and internodes become shorter from the base to the branch apex. Almeda and Martins (2001) noted that another major difference between Trembleya and Lavoisiera is the type of dehiscence on fruiting hypanthia which is basal in Lavoisiera and apical in Trembleya. The Serra do Cabral is located in the easternmost part of the Espinhaço Range and is composed of Proterozoic formations of conglomerates, quartzites, and sandstones, with many quartz crystal formations. The landscape of this serra is studded with rock outcrops that are resistant to erosion (IBGE, 1977). The vegetation is predominantly composed of “cerrado” that is replaced by campo rupestre (high elevation rocky-field vegetation) at elevations above 900 m. In this latter vegetation type, the plants of many angiosperm families exhibit vegetative features (rigid leathery leaves of varying postures and xylopodia ) that are adaptations for life in an environment with high insolation, pronounced seasonal rainfall, nutrient-poor soils, and periodic fires (Almeda & Martins, 2001). Serra do Cabral has been identified by the Brazilian government as a priority conservation area of extreme biological importance because of its high incidence of plant endemism

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(Costa et al., 1998; Cavalcanti & Joly, 2002). On September 29, 2005, the area was designated a state park (Parque Estadual da Serra do Cabral – state decree 44.121) by the Instituto Estadual de Florestas de Minas Gerais in recognition of its diverse biota and archeological sites with cave paintings. Its great scenic beauty, plethora of waterfalls, rocky outcrops, and rich biodiversity make it a potential ecotourism destination but the park currently has limited infrastructure to handle such activity. In a first attempt to provide an enumeration of the plant species on Serra do Cabral, Hatschbach et al. (2006) listed four species of Trembleya. Recent work there focused on the Microlicieae indicates that at least nine of the 23 species that we currently recognize in the genus occur on Serra do Cabral and five of them are evidently endemic (Martins, 1997; Almeda & Martins, 2001; Fidanza, 2005). It appears that this serra harbors the largest number of Trembleya species yet registered for any mountain in Brazil. Four of the new species are described and illustrated here. Another seven new species, one of which also appears to be endemic to Serra do Cabral, will be described in a forthcoming revision of the genus. Trembleya inversa K. Fidanza, A. B. Martins & Almeda, sp. nov. Type: Brazil. Minas Gerais: Mun. Joaquim Felício, Serra do Cabral, Armazém da Laje, 1031 m, 17°42’26”S, 44°11’30”W, 9 Sep 2003 (fl, fr), K. Fidanza & R. Belinello 12 (holotype: UEC; isotype: CAS). (Fig. 1) Diagnosis: Openly branched shrub with glabrous branches. Leaves sessile, semiamplexicaul and reflexed, 5–7-nerved with the veins on the adaxial surfaces (like the bracts and bracteoles) conspicuously more prominent than those on the abaxial face, becoming a variegated greenish-yellow color flushed with brown mainly on the abaxial surfaces when dry, both surfaces densely covered with sessile glands, margins sparingly glandular-punctate. Flowers 5-(-6)-merous. Hypanthium glabrous. Petals white. Ovary 4-locular.

Erect, openly branched subshrub or shrub 1.5–2.5 m tall. Branches and branchlets subquadrangular to terete, glabrous. Leaves sessile, semiamplexicaul, reflexed, spreading to crowded and imbricate at the ends of the branchlets; blade 1.5–6.5×0.5–2.5 cm, coriaceous to chartaceous, ovate to ovate-lanceo-

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FIG. 1. Trembleya inversa. A. Habit. B. Ovary cross-section. C. Leaf (adaxial surface) showing undulate sparingly glandular-punctate margin and elevated veins. D. Petal. E. Stamen (antesepalous). F. Stamen (antepetalous). G. Bracteole showing acuminate apex and sparingly glandular-punctate margin. H. Bract (adaxial surface). I. Hypanthium showing acuminate, bluntly apiculate calyx lobes. (Drawn from the type.)

late, base subcordate, apex acute with slightly undulate margin that is sparingly glandularpunctate 5–7-nerved (basal acrodromous), the elevated veins prominent on the adaxial surface but impressed on the abaxial surface, with a conspicuous network of secondary veins, the abaxial surface pale green, the adaxial surface bright green, (both surfaces

densely covered with sessile glands), variegated when dry (mostly on the abaxial surface). Inflorescence a mostly simple dichasium or reduced to paired or solitary terminal and axillary flowers (commonly aggregated at the ends of branchlets). Bracts 6.8–7×2.9– 3 mm, ovate, apex acute, base subcordate, margin entire or slightly undulating at the

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apex, sparingly glandular-punctate, otherwise glabrous, 3-nerved, nerves thickened at the base, and not extending to the apex. Bracteoles 4.7–5×1.6–2 mm, similar to the bracts. Flowers 5(6)-merous; pedicels 2–2.2 mm long. Hypanthium (at anthesis) 2.8–3×2– 2.3 mm, campanulate, glabrous, 10-costate. Calyx lobes 1–1.2×0.4–0.5 mm, linear, apex apiculate, mucronate, margin entire to minutely glandular-ciliolate, both surfaces glabrous. Petals 9.7–10 × 4.8–5 mm, white, obovate, apex long acuminate (mucronate in bud), margin entire. Stamens 10, dimorphic. Antesepalous stamens with filaments 5–5.2 mm long, white, connective prolonged 2–2.3 mm below the thecae, white, appendage ca. 0.2 mm long, flattened dorso-ventrally, yellow, thecae 2.5–2.7 mm long, linear-oblong, yellow, rostrum ca. 1 mm long, white, with a wide ventrally inclined pore. Antepetalous stamens with filaments 4.8–5 mm long, white, connective prolonged 0.8–1 mm below the thecae, white, appendage 1–1.2 mm long, becoming enlarged at the apex, yellow, thecae 1.8–2 mm long, linear-oblong, yellow, rostrum ca. 0.6 mm long, white, tubular, with a wide ventrally inclined pore. Ovary 2–2.2 mm long, oblong, glabrous, superior, 4 -locular. Style 5.8–6 mm long, white, yellow at the apex, straight to slightly curved, glabrous. Capsule (at maturity) 4.5–4.6 mm long, oblong, slightly constricted apically, hypanthium and calyx lobes persistent to tardily caducous. Seeds ca. 0.3 mm long, reniform, the testa foveolate. Distribution and ecology.—Trembleya inversa is known only from Serra do Cabral. The few individuals of this species encountered were growing in damp sandy soils, near rock outcrops in areas dominated by “campo rupestre” at 900 to 1183 m. Phenology.—Flowering from December to March and fruiting in May. Etymology.—The specific epithet refers to the reflexed position of the leaves which gives them an inverted appearance. The venation on the adaxial surfaces of leaves, bracts, and bracteoles are more prominent than those on the abaxial face. Conservation status.—Trembleya inversa is known only from the eastern flank of Serra do Cabral. Based on our field work there, fewer than 20 individuals occur at fewer than five

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locations within an estimated area of occupancy to be considerably less than 500 km2. Based on IUCN criteria (IUCN, 2001, 2011), we recommend a conservation classification of Endangered (EN). Serra do Cabral has protected status and although it is not experiencing pressures from growing human populations or heavy tourism it is subject to periodic fires like so much of the native flora of “campo rupestre” and “cerrado.” Additional specimens examined. BRAZIL. Minas Gerais: Mun. Joaquim Felício, Serra do Cabral, 17 Apr 1981 (fl, fr), Rossi et al. CFCR 1130 (UEC); 950 m, 16 May 2001 (fl, fr), Hatschbach et al. 72056 (MBM); 14 Mar 1997 (fl, fr), Hatschbach et al. 66197 (MBM); 950 m, 16 May 2001 (fl, fr), Hatschbach et al. 72013 (MBM); início da subida, 900 m, 14 Apr 1996 (fl), Hatschbach et al. 64729 (MBM); 8 Aug 1985 (fl, fr), Pirani et al. CFCR 8070 (CAS, SPF); 23.9 kmN of Joaquim Felício at Armazém de Laje, 17˚42’17” S, 44˚17’58” W, 1183 m, 18 Oct 2001 (fr), Almeda et al. 8523 (CAS, UEC); Comecha de Cima, 2 Sep 1985 (fl), Cavalcanti et al. CFCR 8195 (CAS, SPF); Pedreira, 17º42’01”S, 44º11’15”W, 1060 m, 23 Mar 2003 (fl, fr), Fidanza et al. 4 (UEC); ibid, 1060 m, 23 Mar 2003 (fl, fr), Fidanza et al. 15 (UEC); ca. 15 kmN da cidade de Joaquim Felício, 17º43’34”S, 44º10’57”W, 1080 m, 23 Mar 2003 (fl, fr), Fidanza et al. 39 (UEC).

Trembleya inversa is most similar to T. serrulata (a new species described here). Both have ovate leaves with acute apices that are cordate and semi-amplexicaul at their base. However, T. inversa has leaf blades, bracts, and bracteoles covered with sessile glands and leaves with entire margins (vs. stalked glandular trichomes in small depressions on the leaves, margins clearly serrate and glandularciliate in T. serrulata). Trembleya inversa has a 10-costate hypanthium, linear calyx lobes, and white petals (vs. smooth hyanthia, triangular calyx lobes, and pink petals in T. serrulata). Both leaf surfaces of T. inversa are bright-green, but when dry, the leaves, bracts, and bracteoles acquire a variegated greenish-yellow color flushed with brown mainly on the abaxial surfaces. Field observations led to the discovery of an extraordinary feature of T. inversa that has not been reported for any other known species of the genus or any other member of the Melastomataceae. The venation on the adaxial surfaces of leaves, bracts, and bracteoles of this species are more prominent than those on the abaxial face—the opposite of the usual situation for this family. Additionally,

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these structures are reflexed, which gives the leaves an inverted appearance (Fig. 1). Angiosperm leaves that have inverted the positions of their surfaces are described as resupinate, or twisted (as has also been reported for the family AlstroemeriaceaeMonocotyledonae). In these cases, a twisting of the petiole at some stage of leaf development inverts the positions of the vascular bundles. Because the species described here has sessile leaves, speculations on the correct terminology for this phenomenon based only on macroscopic observations seems premature so we have chosen not to categorize this unusual phenomenon at this time. An anatomical study of the leaves, bracts, and bracteoles of T. inversa is being undertaken to examine the position of the vascular bundles as well as the organization and position of the mesophyll (K. Fidanza, in preparation). Trembleya purpurascens K. Fidanza, A. B. Martins & Almeda, sp. nov. Type: Brazil. Minas Gerais: Mun. Joaquim Felício, Serra do Cabral, estrada Joaquim Felício-Armazém da Laje, 988 m, 17°43’37”S, 44°10’52”W, 4 May 2003 (fl, fr), K. Fidanza & R. Belinello 56 (holotype: UEC; isotype: CAS). (Fig. 2) Diagnosis: Much branched, viscous subshrub. Branches densely covered with stalked gland-tipped trichomes (ca. 0.4 mm long). Leaves sessile, 5–7-nerved with the veins more prominent on the abaxial surface, concolored, densely covered with stalked gland-tipped trichomes (ca. 3 mm long) on both surfaces, margin slightly serrate and glandular-ciliolate. Flowers 5-merous. Hypanthium densely covered with stalked glandtipped trichomes. Petals dark purple. Ovary 3-locular.

Erect, much branched, viscous subshrub 1– 1.5 m tall. Branches and branchlets subquadrangular, densely covered with stalked gland-tipped trichomes (ca. 0.4 mm long). Leaves sessile; blade 1.5–4×0.5–3 cm, membranaceous, ovate-lanceolate, concolored, base rounded, apex acute, margin slightly serrate and glandular-ciliolate, densely covered with stalked gland-tipped trichomes (ca. 3 mm long) on both surfaces, 5–7-nerved (basal acrodromous), the primaries adaxially impressed but prominent on the abaxial surface. Inflorescence a simple dichasium (axillary or terminal). Bracts 2.4–2.6×1.6– 1.8 mm, ovate to ovate-elliptic, apex obtuse

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and apiculate, base rounded, margin glandular-ciliolate, both surfaces densely covered with stalked gland-tipped trichomes, 3nerved, veins thickened at the base, with the median vein extending to the middle of the blade and the lateral primaries extending only slightly beyond the base. Bracteoles 3–5× 1.3–1.5 mm, otherwise like the bracts. Flowers 5-merous; pedicels 1.5–1.7 mm long. Hypanthium (at anthesis) 2.8–3×2–2.3 mm, campanulate, densely covered with stalked gland-tipped trichomes, 10-costate. Calyx lobes 1.8–2×0.5–0.6 mm, triangular, apex acuminate, terminating in a stalked glandtipped trichome, margin entire, adaxially glabrous and abaxially covered with stalked gland-tipped trichomes (ca. 1.3 mm long). Petals 9.4–9.5 ×4.5–4.6 mm, dark purple, obovate, apex rounded and shortly apiculate, with a terminal glandular-trichome ca. 1 mm long, margin entire. Stamens 10, dimorphic. Antesepalous stamens with filaments 3.8– 4 mm long, pink, connective prolonged 1.8– 2 mm below the thecae, pink, appendage 2– 2.2 mm long, rounded to inconspicuously lobed, yellow, thecae 1.2–1.4 mm long, oblong, purple, rostrum ca. 0.2 mm long, white with a wide ventrally inclined pore. Antepetalous stamens with filaments 3–3.2 mm long, pink, connective prolonged 0.8–1 mm, pink, appendage ca. 1 mm long, lobed, yellow, thecae 1.6– 1.7 mm long, oblong, yellow, rostrum ca. 0.2 mm long, white with a wide ventrally inclined pore. Ovary 2.2–2.4 mm long, oblong, glabrous, superior, 3-locular. Style 6–6.3 mm long, purple, erect, glabrous. Capsule (at maturity) 3.2–3.3 mm long, oblong, enveloped by the hypanthium, constricted at the apex above the capsule apex, hypanthium and calyx lobes persistent to tardily caducous. Seeds 0.2– 0.3 mm long, oblong, the testa foveolate. Distribution and ecology.—Trembleya purpurascens appears to be endemic to Serra do Cabral. It has been collected in highly modified “campo rupestre” and “cerrado” vegetation. The few individuals found at these localities were growing in areas with sandy and rocky soils at 900 to1000 m. Phenology.—Flowering and fruiting in April and May.

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FIG. 2. Trembleya purpurascens. A. Habit. B. Bracteole (adaxial surface). C. Bract (adaxial surface). D. Leaf (adaxial surface) showing glandular-ciliate margin. E. Stamen (antepetalous). F. Stamen (antesepalous). G. Petal showing terminal glandular trichome. H. Ovary cross-section. I. Hypanthium showing stalked glandular trichomes. (Drawn from the type.)

Etymology.—The specific epithet refers to the dark purple color of the petals. Conservation status.—Trembleya purpurascens is known only from the eastern flank

of Serra do Cabral. Based on our field work there, fewer than 20 individuals occur at three locations within an estimated area of occupancy to be considerably less than 500 km2.

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Based on IUCN criteria (IUCN, 2001, 2011), we recommend a conservation classification of Endangered (EN) because Serra do Cabral is vulnerable to degradation by periodic fires and other pressures like crystal extraction, and the harvesting of bromeliads and other ornamentals. This species was found in highly modified “campo rupestre” and “cerrado.” This may indicate that it is a pioneering species of disturbed sites that can be degraded quickly and irreparably if the disturbance is severe and repetitive. Additional specimens examined. BRAZIL. Minas Gerais: Mun. Joaquim Felício: Serra do Cabral, ca. 14 km N da cidade de Joaquim Felício, 948 m, 17°46’31”S, 44°18’52”W, 2 May 2003 (fl, fr), Fidanza et al. 31 (UEC); Serra do Cabral, 14 Apr 1996 (fl, fr), Hatschbach et al. 64694 (MBM).

Trembleya purpurascens is similar to T. neopyrenaica Naudin in the following characteristics: plant architecture (lateral branches with leaves gradually decreasing in size from the base to the apices of the branches); leaf blades and bracts oval to oval-elliptic; and ovary glabrous. In T. neopyrenaica the petioles are 3–5 mm long (vs. sessile); the higher order venation on abaxial foliar surfaces is prominent and conspicuous (vs. delicate and not prominently elevated); the petals are predominantly white, rarely pink or white with a pink base (vs. dark purple); and the ovary is 5-locular (vs. 3-locular). These two species are allopatric since T. purpurascens is currently known only from Serra do Cabral, Minas Gerais. According to Martins (1997), T. neopyrenaica is known only from Goiás (Chapada dos Veadeiros, Serra do Caiapó, Serra Dourada, and Serra dos Pireneus) at elevations above 1000 m. Both species grow in “campo rupestre” and “cerrado.” Trembleya rubra K. Fidanza, A. B. Martins & Almeda, sp. nov. Type: Brazil. Minas Gerais: Mun. Joaquim Felício, Serra do Cabral, ca. 5 kmS do Armazém da Laje, 1060 m, 17°42’01”S, 44°11’15’W, 4 Dec 2003 (fl, fr), K. Fidanza & R. Belinello 112 (holotype: UEC; isotype: CAS). (Fig. 3) Diagnosis: Dichotomously branched subshrub. Branches densely covered with short-stalked gland-

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tipped trichomes mixed with simple spreading trichomes (ca. 1.5 mm long). Leaves with petioles 2–3 mm long, 5nerved with the veins more prominent on the abaxial surface, dark green or grayish-green flushed with red on both surfaces, densely covered with stalked gland-tipped trichomes on both surfaces and intermixed with simple spreading trichomes, margin ciliate. Flowers 5-merous. Hypanthium sparsely glandular hirsute, reddish. Petals white. Ovary 5-locular.

Erect, dichotomously branched, subshrub 0.8–1.5 m tall. Branches and branchlets subquadrangular when young, densely covered with short-stalked gland-tipped trichomes mixed with spreading simple reddish trichomes (ca. 1.5 mm long), older branches ± rounded and glabrescent. Leaves spreading to loosely or densely imbricate distally; petioles 2–3 mm long; blade 1.5– 2×0.8–1.5 cm, membranaceous, ovate, base rounded, apex acute, margin ciliate, dark green (grayish-green) flushed with red on both surfaces, densely covered with sessile glandular trichomes and intermixed with simple spreading trichomes on both surfaces, 5-nerved (basal acrodromous), the veins on the adaxial surface impressed and prominent on the abaxial surface. Inflorescence mostly simple, axillary and terminal dichasia. Bracts 6–7×3– 4 mm, oblong, apex shortly apiculate, base obtuse, margin ciliolate, covered with simple and gland-tipped trichomes on both surfaces, 3nerved, the median vein extending to the leaf apex, the lateral primaries parallel to the leaf margin and not reaching the blade apex. Bracteoles 4.8–5×2–2.2 mm, similar to the bracts. Flowers 5-merous; pedicels 2.4–2.5 mm long. Hypanthium (at anthesis) 2.8–3×2– 2.2 mm, urceolate, sparsely glandular-hirsute, reddish, 10-costate. Calyx lobes 1.8–3×0.9– 1 mm, reddish, triangular, apex acuminate and long apiculate (ca. 2 mm long), margin entire, adaxially glabrous and abaxially moderately hirsute. Petals 10.3–10.5×5.3–5.5 mm, white, obovate, with a simple terminal trichome ca. 1.5 mm long, margin ciliate. Stamens 10, dimorphic. Antesepalous stamens with filament 3.8–4 mm long, yellow, connective prolonged 2.8–3 mm below the thecae, reddish, appendage ca. 2 mm long, flattened and bilobed at the apex, yellow, thecae 1.8–2 mm long, linear-oblong, reddish, rostrum ca. 0.3 mm long, white, with a wide ventrally inclined pore. Antepetalous stamens with filaments 3–3.2 mm long, yellow,

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FIG. 3. Trembleya rubra. A. Habit. B. Bracteole (adaxial surface) showing simple and glandular trichomes. C. Bract (adaxial surface). D. Ovary cross-section. E. Leaf (adaxial surface showing simple trichomes). F. Hypanthium showing glandular trichomes mixed with simple smooth trichomes. G. Stamen (antesepalous). H. Stamen (antepetalous) showing appendage detail. (Drawn from the type.)

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connective shortly prolonged ca. 2 mm, reddish, appendage 0.3–0.4 mm long, truncate at the apex, yellow, thecae 1.5–1.6 mm long, oblong, yellow, rostrum ca. 0.2 mm long, white, with a wide ventrally inclined pore. Ovary 1.8–2 mm long, oblong, glabrous, superior, 5-locular. Style 6.4–6.5 mm long, reddish, glabrous, curved at the apex. Capsule (at maturity) 4.8–5 mm long, globose, reddish, the hypanthium constricted above the capsule and bearing persistent to tardily caducous calyx lobes. Seeds ca. 0.2 mm long, reniform, the testa foveolate. Distribution and ecology.—Trembleya rubra is known only from Serra do Cabral where it occurs in disturbed “cerrado” vegetation. The few individuals found at this locality grow on sandy/rocky soils along roadsides at 900 to1060 m. Phenology.— Flowering and fruiting from August to December. Etymology.—The specific epithet refers to the red coloration of the leaves (when fresh), hypanthia, calyx lobes, and style. Both fresh and dried leaves have the same continuous red coloring along the margins. Conservation status.—Trembleya rubra is also known only from the eastern flank of Serra do Cabral. Based on our field work there, fewer than ten individuals occur at what amounts to two populations within an estimated area of occupancy to be considerably less than 100 km2. Based on IUCN criteria (IUCN, 2001, 2011), we recommend a conservation classification of Critically Endangered (CR). The small number of known individuals leaves this species vulnerable to extirpation since it presently occurs in disturbed “cerrado which is susceptible to periodic fires. Additional specimens examined. BRAZIL. Minas Gerais: Mun. Buenópolis: Serra do Cabral, Estrada Real, 23 Aug 2003 (fl, fr), Hatschbach et al. 73783 (MBM); Mun. Joaquim Felício: Serra do Cabral, Torre da Antena, 1060 m, 17°45’01”S, 44°11’15”W, 4 Dec 2003 (fl, fr), Fidanza et al. 126 (UEC).

Trembleya rubra differs from other congeners in having short axillary branches with 2 or 3 pairs of leaves that appear to be verticillate and produced from the same node. This unusual crowding of leaves is created by the considerable reduction in the length of internodes on axillary branches. The leaf margins, hypanthia,

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calyx lobes, both whorls of anthers, style, and mature capsules (which are enveloped by the hypanthium) all have a reddish color. Among described species, T. rubra is most similar to T. neopyrenaica. Both species have ovate to ovate-oblong leaf blades and 5locular ovaries. The major differences involve petal color and the nature of the indumentum. In T. neopyrenaica, the petals are white but they become pink with age whereas the petals of T. rubra remain white throughout anthesis. The indumentum on branch internodes and hypanthia of T. neopyrenaica consists of short, spreading gland-tipped trichomes of uniform length (vs. a mixture of short spreading glandtipped trichomes and much longer smooth eglandular trichomes). Foliar indumentum between the two species is also consistently different. In T. neopyrenaica, the indumentum on both surfaces consists of short spreading gland-tipped trichomes whereas that of T. rubra consists of a mixture of simple spreading trichomes and sessile glandular trichomes. Trembleya serrulata K. Fidanza, A. B. Martins & Almeda, sp. nov. Type: Brazil. Minas Gerais: Mun. Joaquim Felício, Serra do Cabral, Pedreira, 1,033 m, 17°42’36”S, 44°11’27”W, 7 Dec 2003, (fl, fr), K. Fidanza 108 (holotype: UEC; isotype: CAS). (Fig. 4) Diagnosis: Little-branched subshrub. Branches glabrous throughout. Leaves sessile and somewhat amplexicaul, 5–7-nerved with the veins more prominent on the abaxial surface, adaxial surface light green and abaxial surface dark green, covered with stalked gland-tipped trichomes that arise from depressions on both surfaces, margin irregularly serrate (serrations ca. 1 mm long). Flowers 5-merous. Hypanthium glabrous. Petals pink. Ovary 4-locular.

Erect little-branched subshrubs, 0.7–1 m tall. Branches quadrangular, glabrous. Leaves sessile; blade 4–6×1.5–2 cm, coriaceous to chartaceous, lanceolate, base cordate and somewhat amplexicaul, apex acuminate and short-apiculate, with glandular-ciliate, irregularly serrate margins (the serrations ca. 1 mm long), adaxial surface light green and abaxial face dark green, 5–7-nerved (basal acrodromous), the veins canaliculate on the adaxial surface and prominent on the abaxial surface, both surfaces covered with stalked gland-

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FIG. 4. Trembleya serrulata. A. Habit. B. Stamen (antesepalous). C. Stamen (antepetalous). D. Leaf (adaxial surface) showing serrate margin and glandular trichomes arising from small depressions (in d’). E. Hypanthium showing acuminate apex and adaxial surface of apiculate calyx lobe with sessile glands. F. Petal. G. Bract (adaxial surface). H. Bracteole (abaxial surface). I. Ovary cross-section. (Drawn from the type.)

tipped trichomes that arise from depressions on the leaf surface. Inflorescence consisting

of simple or compound axillary and/or terminal dichasia. Bracts 5–6×1.5–2 mm, ovate,

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apex acuminate, base slightly cordate, somewhat amplexicaul, apiculate, margin serrate and glandular-ciliate, both surfaces covered with stalked gland-tipped trichomes nested in small depressions, 3–4-nerved (basal acrodromous), nerves thickened at the base, the median and lateral primaries extending to the blade apex. Bracteoles 3–3.5 × 1.2– 1.4 mm, similar to the bracts. Flowers 5merous; pedicels 2.5–2.6 mm long. Hypanthium (at anthesis) 4.2–4.3 × 2–2.3 mm, campanulate, glabrous. Calyx lobes 0.8– 1 ×0.6–0.7 mm, triangular, apex acuminate, margin glandular-ciliate, the adaxial surface glabrous, the abaxial surface sparsely covered with sessile glandular trichomes. Petals 5–5.2×3.5–3.6 mm, pink, oval, apex acuminate and slightly apiculate, margin entire. Stamens 10, dimorphic. Antesepalous stamens with filaments 3.2–3.4 mm long, white, connective prolonged 3.4– 3.5 mm below the thecae, the pink appendage ca. 2 mm long, expanded at the apex, yellow, thecae 2–2.2 mm long, oblong, yellow, rostrum ca. 0.7 mm long, white with a ventrally inclined pore. Antepetalous stamens with filaments 0.9–1.2 mm long, white, connective prolonged ca. 1.2 mm, the pink appendage 1– 1.2 mm long, little-expanded, thecae 1.8–2 mm long, oblong, yellow, rostrum ca. 0.5 mm long, white with a ventrally inclined pore. Ovary 2.4– 2.5 mm long, globular, glabrous, superior, 4locular. Style 4.3–4.5 mm long, white, curved at the apex, glabrous. Capsule (at maturity) 5– 5.2 mm long, oblong, enveloped by the hypanthium and persistent to tardily caducous calyx lobes. Seeds ca. 0.2 mm long, oblong, the testa foveolate. Distribution and ecology.—Trembleya serrulata is known only from “cerrado” areas on the Serra do Cabral, mainly along roadsides with rocky seasonally dry soil at 846 to 1055 m. Phenology.— Flowering and fruiting from August to December. Etymology.—The specific epithet refers to the conspicuously serrulate margins of the leaves. Conservation status.—Trembleya serrulata, like the other novelties described here, is also known only from the eastern flank of Serra do Cabral. Based on our field work and

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five known collections, it appears to have a wider distribution that extends from the southeastern portions of the serra to about nine kilometers north of the town of Joaquim Felício. Again, less than 100 individuals occur in what amount to five populations within an estimated area of occupancy to be considerably less than 500 km2. Based on IUCN criteria (IUCN, 2001, 2011), we recommend a conservation classification of Endangered (EN). The prevalence of this species along roadsides in “cerrado” makes it vulnerable to periodic fires and the eventual possibility of road widening and paving once improved infrastructure is put into place to accommodate tourism. Additional specimens examined. BRAZIL. Minas Gerais: Mun. Augusto de Lima: Serra do Cabral, Morro dos Souzas, 846 m, 18°02’54”S, 44°19’52”W, 7 Dec 2003 (fl, fr), Fidanza et al. 74 (UEC); Mangueira da Casinha da Mina, 1055 m 18°00’44”S, 44°19’37”W, 7 Dec 2003 (fl, fr), Fidanza et al. 80 (UEC); Mun. Buenópolis: Serra do Cabral, ca. 12 kmN da cidade de Buenópolis, 1053 m, 17°55’14”S, 44°14’31”W, 10 Sep 2003 (fl, fr), Fidanza et al. 88 (UEC); Mun. Joaquim Felício: Serra do Cabral, entre o Rio Embalassaia e Rio Preto, 18 Aug 2002 (fr), Hatschbach et al. 73573 (MBM).

Trembleya serrulata is closely related to Trembleya phlogiformis DC. (a species also known from Serra do Cabral and widespread in Minas Gerais). Both species have leaf blades with serrate glandular-ciliate margins. However, T. serrulata has consistently sessile, lanceolate leaf blades with a long acuminate apex and a cordate, semi-amplexicaul base while T. phlogiformis has mostly subsessile or petiolate (up to 3 mm) leaf blades that are oblong-ovate to elliptic-lanceolate with an acute apex and a broadly rounded base. The branch internodes of T. serrulata are glabrous and the petals are consistently pink whereas the internodes of T. phlogiformis are copiously covered with spreading gland-tipped trichomes of varying sizes and the petals can vary from pink or purplish to white. The similarities between T. serrulata and T. inversa (both of which occur on Serra do Cabral, although in distinct localities) are discussed under the latter species.

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Acknowledgments We thank CAPES (Centro de Aperfeiçoamento do Ensino Superior) for a scholarship granted to Fidanza (FAEPEX/UNICAMP and PROAP/UNICAMP) to support field work, CNPq (Conselho Nacional do Desenvolvimento Científico e Tecnológico) for grant support to Martins, and the M. Stanley Rundel Charitable Trust (U.S.A.) for supporting field work by Almeda and Martins in southeastern Brazil. We also thank two anonymous reviewers for helpful comments, Samira Rolim for preparing all the line drawings, and Rachel Diaz-Bastin and Charlotte Pfeiffer for technical assistance. We are also grateful to the following curators for making the herbarium material under their care readily accessible: Gert Hatschbach (MBM) and José R. Pirani (SPF). Literature Cited Almeda, F. 2003. Melastomataceae, Princess Flowers. Pp. 375–379. In: S. Goodman and J. Benstead, eds., The Natural History of Madagascar. University of Chicago Press, Chicago, Illinois. ——— & A. B. Martins. 2001. New combinations and new names in some Brazilian Microlicieae (Melastomataceae), with notes on the delimitation of Lavoisiera, Microlicia, and Trembleya. Novon 11: 1–7. Candolle, A. P de. 1828. Melastomaceae. Pp. 99–202. In: Prodromus systematics naturalis regni vegetabilis, vol. 3. Treuttel & Würtz, Paris. Cavalcanti, R. B. & C. A. Joly. 2002. Biodiversity and conservation priorities in the cerrado region. Pp. 351– 367 In: P. S. Oliveira and R. J. Marquis, eds., The Cerrados of Brazil. Columbia University Press, New York, New York.

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Claussing, G. & S. S. Renner. 2001. Molecular phylogenetics of Melastomataceae and Memecylaceae: implications for character evolution. American Journal of Botany 88(3): 486–498. Costa, C. M. R., G. Herrmann, C. S. Martins, L. V. Lins & I. R. Lamas (orgs). 1998. Biodiversidade em Minas Gerais: Um atlas para sua conservação. Fundação Biodiversitas. Belo Horizonte, Brazil. Fidanza, K. 2005. A tribo Microlicieae (Melastomataceae) na Serra do Cabral, Minas Gerais, Brasil. Dissertação de Mestrado. Universidade Estadual de Campinas. Campinas, São Paulo, Brazil. Fritsch, P. W., F. Almeda, S. S. Renner, A. B. Martins & B. C. Cruz. 2004. Phylogeny and circumscription of the near-endemic Brazilian tribe Microlicieae (Melastomataceae). American Journal of Botany 91(7): 1105–1114. Goldenberg, R., J. F. A. Baumgratz & M. L. D’El Rei Souza. 2012. Taxonomia de Melastomataceae no Brasil: retrospectiva, perspectivas e chave de identificação para os gêneros. Rodriguésia 63: 145–161. Hatschbach, G., E. A. E. Guarçoni, M. A. Sartori & O. dos Santos Ribas. 2006. Aspectos fisonômicos da vegetação da Serra do Cabral, Minas Gerais-Brasil. Boletim do Museu Botânica Municipal 67: 1–33. IBGE. 1977. Fundação Instituto Brasileiro de Geografia e Estatística. Geografia do Brasil 3: Região Sudeste. Rio de Janeiro, Brazil. IUCN. 2001. IUCN Red List Categories and Criteria: Version 3.1. Prepared by the IUCN Species Survival Commission. IUCN, Gland and Cambridge. IUCN. 2011. Guidelines for using the IUCN Red List Categories and Criteria. Version 9.0. Downloadable from http:// www.iucnredlist.org/documents/RedListGuidelines.pdf. Mabberley, D. J. 2008. Mabberley’s Plant Book. Cambridge Univeristy Press, Cambridge, UK. Martins, E. 1997. Revisão taxonômica do gênero Trembleya DC. (Melastomataceae). Tese de Doutorado. Universidade Estadual de Campinas, São Paulo, Brazil. Mittermeier, R. A., P. R. Gil, M. Hoffmann, J. Pilgrim, T. Brooks, C. G. Mittermeier, J. Lamoreux & G. A. B. Fonseca. 2004. Hotspots revisited. CEMEX/ Agrupación Sierra Madre. Mexico City.