Trixis forzzae (Compositae: Mutisieae), a new species from Minas Gerais, Brazil

August 24, 2017 | Autor: Mariana Saavedra | Categoria: Evolutionary Biology, Plant Biology, Minas Gerais, Geographic distribution
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KEW BULLETIN VOL. 65: 65–68 (2010)

Trixis forzzae (Compositae: Mutisieae), a new species from Minas Gerais, Brazil Rafael Augusto Xavier Borges1 & Mariana Machado Saavedra1 Summary. The new species Trixis forzzae Borges & Saavedra, from Serra do Ibitipoca, Minas Gerais, Brazil is des-

cribed and illustrated. Taxonomic relationships with similar species and those of similar geographical distribution are discussed. Key Words. campo rupestre, Compositae, flora, taxonomy.

Introduction Trixis P. Browne is represented by up to 60 species and is included in subtribe Nassauviinae (Compositae, Mutisieae) (Hind 2007). It is distinguished from other genera in the subtribe by the presence of capitula that are never solitary, with pubescent and epaleaceous receptacles (Katinas 1996). The genus has a neotropical distribution, ranging from the southern United States to central Argentina; 14 species are recorded from Brazil, mainly occurring in Minas Gerais and São Paulo states (Katinas 1996; Hind 2000). The Espinhaço and Mantiqueira Ranges in southeastern Brazil have high levels of plant species richness and endemicity, with a high concentration of Compositae species documented (Giulietti & Pirani 1988; Harley 1995; Safford 1999; Giulietti et al. 2005). The former range is predominantly located in the Cerrado biome and the latter in the Atlantic Forest (Giulietti & Pirani 1988; Safford 1999). The Serra do Ibitipoca is located in a transitional area between these ranges (Map 1), and comprises many different habitats, the most dominant of which is campo rupestre vegetation (Menini-Neto et al. 2007). Despite the importance of mountain systems for plant species diversity and endemism in the tropics, several Brazilian mountains are still taxonomically unknown and many are not included in conservation units (Martinelli 2007). Recently, during work for the Flora do Parque Estadual do Ibitipoca, a new species of Trixis was discovered which is described and illustrated below. Trixis forzzae Borges & Saavedra sp. nov. T. glaziovii Baker affinis sed caulibus lanuginosis, non alatis, foliis chartaceis, non rosulatis et inflorescentia corymbosa

differt. Typus: Brazil, Estado de Minas Gerais, 27 May 2005, Saavedra, Forzza, Andrade & Pereira 239 (holotypus RB!; isotypus K!). Erect subshrub 0.5 – 1 m. Stem woody, sparsely leafy, densely woolly, with simple, eglandular, rusty hairs. Leaves spirally arranged, sessile, (2.5 –) 3.5 – 9 (– 12) × (0.8 –) 1 – 2.5 (– 3.5) cm, chartaceous, oblanceolate to lanceolate, base attenuate, apex acute, margins minutely dentate, venation reticulodromus, abaxially woolly with prominent midrib, adaxially hirsute. Inflorescence terminal, with corymb-like branches, bracteolate, bracteoles 0.6 – 1.6 (– 2) × 0.3 – 0.7 (– 0.9) cm, oblong to lanceolate, base obtuse, apex acute, margin entire, both surfaces hirsute, hairs densely grouped on midrib and margins. Capitula pedicellate, pedicels (0.7 –) 1.5 – 6 cm long, woolly; involucre hemispherical, biseriate, external phyllaries c. 8, leafy, 7 – 8 × 2 – 3 mm, oblong, hirsute, internal phyllaries c. 23, rigid, c. 10 × 2 mm, lanceolate; receptacle epaleaceous, dense pubescent. Florets hermaphrodite, c. 58, yellowish; corolla 1 – 1.2 cm long, glabrous, outer lip c. 6 × 3 mm, erect to slightly revolute, inner lip 4 – 5 × 1 mm, coiled; anther c. 6 mm long, apical anther appendages lanceolate, basal anther appendages c. 2 mm long, glabrous; style c. 8 mm long, style branches c. 1.5 mm long. Cypselas c. 6 mm long, cylindrical, base truncate, with 8 longitudinal ribs, hirsute, glandular; pappus 1-seriate, 8 – 9 mm long, barbellate, pale yellow, persistent. Fig. 1. DISTRIBUTION. Only recorded from Serra do Ibitipoca in southern Minas Gerais state, Brazil.

Accepted for publication September 2009. 1 Programa de Pós-Graduação em Botânica, Escola Nacional de Botânica Tropical, Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Rua Pacheco Leão, 2040, 22460-030, Rio de Janeiro, Brazil. e-mail: [email protected]

© The Board of Trustees of the Royal Botanic Gardens, Kew, 2010



Map 1. Location of the Parque Estadual do Ibitipoca in Minas Gerais, showing vegetation types occurring in the State.

BRAZIL. Minas Gerais: Município de Lima Duarte: Parque Estadual do Ibitipoca, logo abaixo do Cruzeiro, 27 May 2005, Saavedra, Forzza, Andrade & Pereira 239 (holotype RB; isotype K); Lombada, 20 June 1991, Salimena-Pires s.n. (CESJ 24766); Gruta dos 3 Arcos, 21°40 ′44 ″S, 43°52 ′59 ″W, 1670 m elev., 26 July 2004, Forzza, Magenta, Aona, Berman, Saavedra & Zappi 3518 (RB); base do Pico do Peão, 16 May 2006, Saavedra, Borges, Forzza, Pereira, Ribeiro & Avelar 285 (RB). HABITAT. Campos rupestres, among rocks and herbaceous vegetation with sparse shrubs and small trees. CONSERVATION STATUS. Data on distribution and abundance of Trixis forzzae are restricted to the type locality. Consequently, the endemicity of this species is recognised such as that observed before in the Park for species of Bromeliaceae, Velloziaceae, Poaceae, Melastomataceae and Gesneriaceae. Thus it seems prudent to treat it as Vulnerable (VU) D1 + D2, following the IUCN (2001) categories and criteria. © The Board of Trustees of the Royal Botanic Gardens, Kew, 2010

ETYMOLOGY. This species is named for Rafaela Campostrini Forzza, curator of RB, Coordinator of the Flora do Parque Estadual do Ibitipoca and our personal friend. NOTES. Trixis forzzae is closely related to T. glaziovii Baker, but clearly differs by the presence of dense woolly indument; wingless stems; leaves not rosulate, chartaceous, with the base attenuated; corymblike inflorescence. Furthermore, both species occur in distinct habitats: Trixis forzzae is only known from the campos rupestres (Giulietti & Pirani 1988) of Serra do Ibitipoca, and T. glaziovii from the campos de altitude (Safford 1999) of southern and south-eastern Brazil. Among the Brazilian species, Trixis glaziovii and T. lessingii DC. are considered herbaceous, with rosulate leaves and a fistulose stem (Katinas 1996). However, T. forzzae is a subshrub, characterised by the lack of rosulate leaves and by the woody and branched stem. Among the shrubby species, only T. forzzae and



Fig. 1. Trixis forzzae. A habit; B woolly indumentum; C detail of upper leaf surface; D capitulum; E floret; F cypsela; G outer phyllary; H inner phyllary. A – D, G, H from Saavedra et al. 239; F from Forzza et al. 3518. DRAWN BY MARIA ALICE REZENDE.

© The Board of Trustees of the Royal Botanic Gardens, Kew, 2010


T. verbascifolia (Gardner) S. F. Blake have folicaceous external phyllaries. Nevertheless, the latter can be distinguished by its radiate capitula and 3 – 4-seriate phyllaries.

Acknowledgements We are grateful to Parque Estadual do Ibitipoca staff and Instituto Estadual de Florestas (IEF – MG). The line drawing was prepared by Maria Alice Rezende.

References Giulietti, A. M. & Pirani, J. R. (1988). Patterns of geographic distribution of some plant species from the Espinhaço Range, Minas Gerais, Brazil. In: P. E. Vanzolini & W. R. Heyer. (eds), Proceedings of a Workshop on Neotropical Biodiversity Distribution Patterns, pp. 39 – 69. Academia Brasileira de Ciências, Rio de Janeiro. ____, Harley, R. M., Queiroz, L. P., Wanderley, M. G. L. & Van Den Berg, C. (2005). Biodiversity and conservation of plants in Brazil. Conserv. Biol. 19: 632 – 639.

© The Board of Trustees of the Royal Botanic Gardens, Kew, 2010


Harley, R. M. (1995). Introdução. In: B. L. Stannard (ed.), Flora of the Pico das Almas, Chapada Diamantina, Brazil, pp. 1 – 42. Royal Botanic Gardens, Kew. Hind, D. J. N. (2000). A new species and a commentary on the genus Trixis (Compositae: Mutisieae) in Bahia, Brazil. Kew Bull. 55: 381– 386. ____ [2006] (2007). Tribe Mutisieae. In: J. W. Kadereit & C. Jeffrey (vol. eds), The Families and Genera of Vascular Plants (K. Kubitzki, series ed.), Vol. VIII. Flowering Plants, Eudicots, Asterales, pp. 90 – 122. Springer, Berlin, Heidelberg, New York. IUCN (2001). IUCN Red List Categories and Criteria: Version 3.1. IUCN Species Survival Commission. IUCN, Gland, Switzerland and Cambridge, UK. Katinas, L. (1996). Revisión de las especies sudamericanas del género Trixis (Asteraceae, Mutisieae). Darwiniana 34: 27 – 108. Martinelli, G. (2007). Mountain biodiversity in Brazil. Revista Brasil. Bot. 30: 587 – 597. Menini-Neto, L., Alves, R. J. V. & Forzza, R. C. (2007). A subtribo Pleurothallidinae (Orchidaceae) no Parque Estadual de Ibitipoca, Minas Gerais, Brasil. Bol. Bot. Univ. São Paulo 25: 253 – 278. Safford, H. F. (1999). Brazilian Páramos I. An introduction to the physical environment and vegetation of the campos de altitude. J. Biogeogr. 26: 693 – 712.

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