Plant Ecology and Evolution 153(2): 246-256, doi: 10.5091/plecevo.2020.1669
Two new Critically Endangered species of Ditassa (Apocynaceae) from the threatened cangas of the Iron Quadrangle, Minas Gerais, Brazil
expand article infoCassia Bitencourt, Moabe Ferreira Fernandes§, Fábio da Silva do Espírito Santo|, Alessandro Rapini
‡ UEFS, Feira de Santana, Brazil§ Universidade Estadual de Feira de Santana, Feira de Santana, Brazil| Centro de Formação em Tecnociências e Inovação, Universidade Federal do Sul da Bahia, Rua Itabuna, s/n, Rod. Ilhéus – Vitória da Conquista, km 39, BR 415, Ferradas, 45613-204, Itabuna Bahia, Brazil¶ Universidade Estadual de Feira de Santana, Feira de Santana, Bahia, Brazil
Open Access

Background and aims – Vegetation on ironstone outcrops is highly threatened, particularly due to the impact of mining. In this study, two new species of Ditassa (Metastelmatinae, Asclepiadoideae, Apocynaceae) from the cangas of the Iron Quadrangle (Minas Gerais, Brazil) are described and illustrated, and their conservation status is discussed.

Material and methods – Species recognition is based on a morphological and molecular study of recent and historical collections, including a survey of the main herbaria of Brazil, Europe and the United States. Conservation status assessments are based on the evaluation of areas of occupancy and the impact of iron mining in the region.

Key results – The two new species are morphologically similar to species in the “Hemipogon from the Espinhaço” clade, which includes Morilloa. Nevertheless, they exhibit flowers with a double corona and are described in Ditassa here, following preliminary phylogenetic analyses with 73 plastid-coding regions. These species are known from only two highly disturbed locations each and are Critically Endangered. A key to identify the 14 species of Metastelmatinae currently recorded in cangas of the Iron Quadrangle is provided.

Conclusion – The Critically Endangered Ditassa cangae and D. ferricola are examples of poorly known, nearly extinct species under strong anthropogenic pressure caused by intense mining activities and the lack of adequate legislation for the protection of canga landscapes.

Asclepiadoideae, campos rupestres, conservation, Espinhaço Range, Hemipogon, iron outcrops, Metastelmatinae, mining, threatened species


  • Abessa D., Famá A., Buruaem L. (2019) The systematic dismantling of Brazilian environmental laws risks losses on all fronts. Nature Ecology & Evolution 3: 510–511.
  • ANM – Agência Nacional de Mineração (2019) Classificação de Barragens de Mineração. Available at [accessed 18 Feb. 2019].
  • ANM – Agência Nacional de Mineração (2018) Sumário Mineral Brasileiro 2017: ferro. Available at [accessed 28 Aug. 2019].
  • Bachman S., Moat J., Hill A.W., Torre J., Scott B. (2011) Supporting red list threat assessments with GeoCAT: geospatial conservation assessment tool. ZooKeys 150: 117–126.
  • Beentje H. (2016) The Kew plant glossary – an illustrated dictionary of plant terms. Kew, Royal Botanic Gardens.
  • Biodiversitas (2011) Consulta à Revisão das Listas das Espécies da Flora Ameaçadas de Extinção do Estado de Minas Gerais. Available at [accessed 19 Mar. 2019].
  • Bitencourt C. (2019) Explorando a diversificação das Apocynaceae na era da filogenômica, com ênfase nas espécies de Hemipogon. PhD Thesis, Universidade Estadual de Feira de Santana, Brazil.
  • Bitencourt C., Rapini A., Damascena L.S., De Marco Jr P. (2016) The worrying future of the endemic flora of a tropical mountain range under climate change. Flora 218: 1–10.
  • Brazilian Ministry of the Environment (2014) Portaria MMA No 443, de 17 de dezembro de 2014. Available at [accessed 20 Mar. 2020].
  • Buchanan G.M., Butchart S.H.M., Dutson G., Pilgrim J.D., Steininger M.K., Bishop K.D., Mayaux P. (2008) Using remote sensing to inform conservation status assessment: Estimates of recent deforestation rates on New Britain and the impacts upon endemic birds. Biological Conservation 141(1): 56–66.
  • Câmara R., Câmara G., Andrade Neto, M., Milosevic T., Andrade J.C., Rocha P. (2019) Reserve assessment and certification of Brazil’s oil and mineral sectors and energy storage: New trends, analysis, and regulatory proposals. Resources Policy 62: 347–356.
  • Carmo F.F., Kamino L.H.Y., Tobias Jr R., Campos I.C., Carmo F.F., Silvino G., Castro K.J.S.X., Mauro M.L., Rodrigues N.U.A., Miranda M.P.S., Pinto, C.E.F. (2017) Fundão tailings dam failures: The environment tragedy of the largest technological disaster of Brazilian mining in global context. Perspectives in Ecology and Conservation 15(3): 145–151.
  • Conceição A.A., Rapini A., Carmo F.F., Brito J.C., Silva G.A., Neves S.P.S., Jacobi C.M. (2016) Rupestrian grassland vegetation, diversity, and origin. In: Fernandes G.W. (ed.) Ecology and conservation of mountaintop grasslands in Brazil: 105–127. Basel, Springer International Publishing.
  • Endress M.E., Meve U., Middleton D.J., Liede-Schumann S. (2018) Apocynaceae. In: Kadereit J., Bittrich V. (eds) The families and genera of vascular plants 15. Flowering plants. Eudicots. Apiales, Gentianales (except Rubiaceae): 207–411. Cham, Springer.
  • Fernandes W.F., Goulart F.F., Ranieri B.D., Coelho M.S., Dales K., Boesche N., Bustamante M., Carvalho F.A., Carvalho D.C., Dirzo R., Fernandes S., Galetti Jr P.M., Millan V.E.G., Mielke C., Ramirez J.L., Neves A., Rogass C., Ribeiro S.P., Scariot A., Soares-Filho B. (2016) Deep into the mud: ecological and socio-economic impacts of the dam breach in Mariana, Brazil. Natureza & Conservação 14: 35–45.
  • Ferrante L., Fearnside P.M. (2019) Brazil’s new president and ‘ruralists’ threaten Amazonia’s environment, traditional peoples and the global climate. Environmental Conservation 46(4): 261–263.
  • Fontella-Pereira J., Santos R.G.P., Goes M.B., Moral S.A.C. (2014) Notas taxonómicas sobre Hemipogon subgen. Astephanopsis, y descripción de un nuevo género (Apocynaceae, Asclepiadoideae, Asclepiadeae, Metastelmatinae). Bonplandia 23(1): 25–31.
  • Gagen E.J., Levett A., Paza A., Gastauer M., Caldeira C.F., Valadares R.B.S., Bitencourt J.A.P., Alves R., Oliveira G., Siqueira J.O., Vasconcelos P.M., Southam G. (2019) Biogeochemical processes in canga ecosystems: armoring of iron ore against erosion and importance in iron duricrust restoration in Brazil. Ore Geology Reviews 107: 573–586.
  • Giulietti A.M., Rapini A., Andrade M.J.G., Queiroz L.P., Silva J.M.C. (2009) Plantas raras do Brasil. Belo Horizonte, Conservation International.
  • IBRAM – Instituto Brasileiro de Mineração (2018) Relatório anual de atividades: julho 2017 a junho 2018. Available at [accessed 29 May 2019].
  • IUCN (2017) Guidelines for using the IUCN Red List Categories and Criteria. Version 13. Prepared by the Standards and Petitions Sub-Committee. Available at [accessed 21 May 2019].
  • Jacobi C.M., Carmo F.F. (2008) The contribution of ironstone outcrops to plant diversity in the Iron Quadrangle, a threatened Brazilian landscape. Ambio 37(4): 324–326.
  • Jacobi C.M., Carmo F.F. (2012) Diversidade dos campos rupestres ferruginosos no Quadrilátero Ferrífero. Belo Horizonte, Código editora.
  • Knapp S., Stehmann J.R., Giacomin L.L. (2015) New species, additions and a key to the Brazilian species of the Geminata clade of Solanum L. (Solanaceae) in Brazil. PhytoKeys 47: 1–48.
  • Liede-Schumann S., Nikolaus M., Silva U.C.S., Rapini A., Mangelsdorff R.D., Meve U. (2014) Phylogenetics and biogeography of the genus Metastelma (Apocynaceae-Asclepiadoideae-Asclepiadeae: Metastelmatinae). Systematic Botany 39(2): 594–612.
  • Miola D.T.B., Marinho A.P., Dayrell R.L.C., Silveira F.A.O. (2019) Silent loss: misapplication of an environmental law compromises conservation in a Brazilian biodiversity hotspot. Perspectives in Ecology and Conservation 17(2): 84–89.
  • Mittermeier R.A., Gil P.R., Hoffman M., Pilgrim J., Brooks T., Mittermeier C.G., Lamoreux J., Fonseca G.A.B. (2005) Hotspots revisited: Earth’s biologically richest and most endangered terrestrial ecoregions. Washington, Conservation International.
  • Mota N.F.O., Watanabe M.T.C., Zappi D.C., Hiura A.L., Pallos J., Viveiros R., Giulietti A.M., Viana P.L. (2018) Amazon canga: the unique vegetation of Carajás revealed by the list of seed plants. Rodriguésia 69(3): 1435–1488.
  • Myers N., Mittermeier R.A., Mittermeier C.G., Fonseca G.A.B., Kent J. (2000) Biodiversity hotspots for conservation priorities. Nature 403: 853–858.
  • OECD – Organization for Economic Co-Operation and Development (2017) Local content policies in minerals-exporting countries: The case of Brazil. Available at [accessed 12 May 2020].
  • Rapini A. (2012) Apocynaceae. In: Jacobi C.M., Carmo F.F. (eds) Diversidade florística nas cangas do Quadrilátero Ferrífero: 72–75. Belo Horizonte, Código editora.
  • Rapini A., Mello-Silva R., Kawasaki M.L. (2002) Richness and endemism in Asclepiadoideae (Apocynaceae) from the Espinhaço Range of Minas Gerais, Brazil – a conservationist view. Biodiversity and Conservation 11: 1733–1746.
  • Rapini A., Ribeiro P.L., Lambert S., Pirani J.R. (2008) A flora dos campos rupestres da Cadeia do Espinhaço. Megadiversidade 4: 16–24.
  • Ribeiro P.L., Rapini A., Silva U.C.S., Konno T.U.P., Damascena L.S., Berg, C. (2012) Spatial analyses of the phylogenetic diversity of Minaria (Apocynaceae): assessing priority areas for conservation in the Espinhaço Range, Brazil. Systematics and Biodiversity 10(3): 317–331.
  • Ribeiro, P.L., Rapini A., Damascena L.S., Berg C. (2014) Plant diversification in the Espinhaço Range: Insights from the biogeography of Minaria (Apocynaceae). Taxon 63(6): 1253–1264.
  • Salles D.M., Carmo F.F., Jacobi C.M. (2018) Habitat loss challenges the conservation of endemic plants in mining-targeted Brazilian mountains. Environmental Conservation 46(2): 140–146.
  • Santini L., Butchart S.H., Rondinini C., Benítez‐López A., Hilbers J.P., Schipper A.M., Cengic M., Tobias J.A., Huijbregts M.A. (2019) Applying habitat and population‐density models to land‐cover time series to inform IUCN Red List assessments. Conservation Biology 33(5): 1084–1093.
  • Shuster D.L., Farley K.A., Vasconcelos P.M., Balco G., Monteiro H.S., Waltenberg K., Stone J.O. (2012) Cosmogenic 3He in hematite and goethite from Brazilian “canga” duricrust demonstrates the extreme stability of these surfaces. Earth and Planetary Science Letters 329–330: 41–50.
  • Silva J.M.C., Rapini A., Barbosa L.C.F., Torres R.R. (2019) Extinction risk of narrowly distributed species of seed plants in Brazil due to habitat loss and climate change. PeerJ 7: e7333.
  • Silva M.F.F. (1991) Análise florística da vegetação que cresce sobre canga hematítica em Carajás – Pará (Brasil). Boletim do Museu Paraense Emílio Goeldi - Ciências Naturais 7(1): 79–105.
  • Silva U.C.S., Rapini A., Liede-Schumann S., Ribeiro P.L., Berg C. (2012) Taxonomic considerations on Metastelmatinae (Apocynaceae) based on plastid and nuclear DNA datasets. Systematic Botany 37(3): 795–806.
  • Silveira F.A.O., Negreiros D., Barbosa N.P.U., Buisson E., Carmo F.F., Carstensen D.W., Conceição A.A., Cornelissen T.G., Echternacht L., Fernandes G.W., Garcia Q.S., Guerra T.J., Jacobi C.M., Lemos-Filho J.P., Le Stradic S., Morellato L.P.C., Neves F.S., Oliveira R.S., Schaefer C.E., Viana P.L., Lambers H. (2016) Ecology and evolution of plant diversity in the endangered campo rupestre: a neglected conservation priority. Plant and Soil 403: 129–152.
  • Skirycz A., Castilho A., Chaparro C., Carvalho N., Tzotzos G., Siqueira J.O. (2014) Canga biodiversity, a matter of mining. Frontiers in Plant Science 5: 1–8.
  • Souza-Filho P.W.M., Gianini T.C., Jaffé R., Giulietti A.M., Santos D.C., Nascimento Jr W.R., Guimarães J.T.F., Costa M.F., Imperatriz-Fonseca V.L., Siqueira J.O. (2019) Mapping and quantification of ferruginous outcrop savannas in the Brazilian Amazon: A challenge for biodiversity conservation. PLOS ONE 14: e0211095.
  • Thiers B. (continuously updated) Index Herbariorum: A global directory of public herbaria and associated staff. New York Botanical Garden’s Virtual Herbarium. Available at [accessed 29 May 2019].
  • Tracewski Ł., Butchart S.H.M., Marco M.D., Ficetola G.F., Rondinini C., Symes A., Wheatley H., Beresford A.E., Buchanan G.M. (2016) Toward quantification of the impact of 21st-century deforestation on the extinction risk of terrestrial vertebrates. Conservation Biology 30(5): 1070–1079.
  • Versieux L.M., Machado T.M. (2012) A new ornithophilous yellow-flowered Vriesea (Bromeliaceae) from Serra do Caraça, Minas Gerais, Brazil. Phytotaxa 71: 36–41.
  • Viana P.L., Lombardi J.A. (2007) Florística e caracterização dos campos rupestres sobre canga na Serra da Calçada, Minas Gerais, Brasil. Rodriguésia 58(1): 159–177.
  • Villén-Pérez S., Mendes P., Nóbrega C., Córtes L.G., De Marco Jr P. (2017) Mining code changes undermine biodiversity conservation in Brazil. Environmental Conservation 45(1): 96–99.
  • Zappi D.C., Moro M.F., Walker B., Meagher T., Viana P.L., Mota N.F.O., Watanabe M.T.C., Nic Lughadha E. (2019) Plotting a future for Amazonian canga vegetation in a campo rupestre context. PLoS ONE 14(8): e0219753.