A peer-reviewed open-access journal PhytoKeys 59: 1–828 (2016) World checklist of hornworts and liverworts 1 doi: 10.3897/phytokeys.59.6261 CHECKLIST http://phytokeys.pensoft.net Launched to accelerate biodiversity research World checklist of hornworts and liverworts Lars Söderström1,*, Anders Hagborg2,*, Matt von Konrat2,*, Sharon Bartholomew-Began3, David Bell4, Laura Briscoe2, Elizabeth Brown5, †, D. Christine Cargill6, Denise P. Costa7, Barbara J. Crandall-Stotler8, Endymion D. Cooper9, Gregorio Dauphin10, John J. Engel2, Kathrin Feldberg11, David Glenny12, S. Robbert Gradstein13, Xiaolan He14, Jochen Heinrichs11, Jörn Hentschel15, Anna Luiza Ilkiu-Borges16, Tomoyuki Katagiri17, Nadezhda A. Konstantinova18, Juan Larraín2, David G. Long19, Martin Nebel20, Tamás Pócs21, Felisa Puche22, Elena Reiner-Drehwald23, Matt A.M. Renner5, Andrea Sass-Gyarmati21, Alfons Schäfer-Verwimp24, José Gabriel Segarra Moragues25, Raymond E. Stotler8, †, Phiangphak Sukkharak26, Barbara M. Th iers27, Jaime Uribe28, Jiří Váňa29, Juan Carlos Villarreal30, Martin Wigginton31, Li Zhang32, Rui-Liang Zhu33 1 Department of Biology, Norwegian University of Science and Technology, N-7491 Trondheim, Norway 2 Department of Science and Education, Field Museum, 1400 South Lake Shore Drive, Chicago, IL 60605– 2496, United States of America 3 Department of Biology, West Chester University, West Chester, PA 19383, United States of America 4 Department of Botany, University of British Columbia, 6270 University Boulevard, Vancouver, BC, V6T 1Z4, Canada 5 Royal Botanic Gardens and Domain Trust, Mrs Macquaries Road, Sydney NSW2000, Australia 6 Centre for Australian National Biodiversity Research, Australian National Herbarium, GPO Box 1600, Canberra, ACT 2601, Australia 7 Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Rua Pacheco Leão 915, 22460-030, Rio de Janeiro, RJ, Brazil 8 Department of Plant Biology, Southern Illinois University, Carbondale, Illinois 62901-6509, United States of America 9 CMNS-Cell Biology and Molecular Genetics, 2107 Bioscience Research Building, University of Maryland, College Park, MD 20742-4451, United States of America 10 Apartado 5-1500, Acosta, Costa Rica 11 Systematic Botany and Mycology, Ludwig Maximilian University of Munich, Menzinger Str. 67, 80638 Munich, Germany 12 Allan Herbarium, Landcare Research, P O Box 69-040, Lincoln 7608, New Zealand 13 Muséum National d’Histoire Naturelle, Department Systématique et Evolution, C.P. 39, 57 Rue Cuvier, 75231 Paris 05, France 14 Botany Unit, Finnish Museum of Natural History, University of Helsinki, P.O. Box 7, Helsinki FI-00014, Finland 15 Department of Systematic Botany with Herbarium Haussknecht and Botanical Garden, Friedrich Schiller University, Fürstengraben 1, 07737 Jena, Germany 16 Museu Paraense Emilio Goeldi, Coordenaçao de Botanica, Av. Magalhaes Barata 376, 66040-1 70 Belem, Para, Brazil 17 Department of Biological Science, Graduate School of Science, Hiroshima University, Kagamiyama 1–3–1, Higashihiroshima- shi, Hiroshima 739–8526, Japan 18 N.A. Avrorin Polar-Alpine Botanical Garden–Institute of Kola SC RAS, 184236 Kirovsk-6, Russia 19 Royal Botanic Garden, Edinburgh EH3 5LR, United Kingdom 20 Staatliches Copyright Lars Söderström et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. 2 Lars Söderström et al. / PhytoKeys 59: 1–828 (2016) Museum für Naturkunde Stuttgart, Rosenstein 1, 70191 Stuttgart, Germany 21 Botany Department, Institute of Biology, Eszterházy Károly College, Eger, Pf. 43, H-3301, Hungary 22 Departamento de Botánica, Facultad de Ciencias Biológicas, Universitat de València. C/ Dr. Moliner 50, E-46100, Burjassot (Valencia), Spain 23 Albrecht-von-Haller-Institut für Pfl anzenwissenschaften, Department of Systematics, Biodiversity and Evolution of Plants, Untere Karspüle 2, 37073 Göttingen, Germany 24 Mittlere Letten 11, 88634 Herdwangen-Schönach, Germany 25 Centro de Investigaciones sobre Desertifi cación (CIDE-CSIC-UV-GV), C/ Carretera de Moncada-Náquera Km. 4.5, E-46113, Moncada (Valencia), Spain 26 Department of Biology, Faculty of Science, Burapha University, Mueang, 20131 Chonburi, Th ailand 27 William and Lynda Steere Herbarium, Th e New York, Botanical Garden, Bronx, New York 10458-5126, United States of America 28 Instituto de Ciencias Naturales. Universidad Nacional de Colombia. Apartado 7495, Bogotá D.C., Colombia 29 Department of Botany, Charles University, Benátská 2, CZ-128 01 Praha 2, Czech Republic 30 Department of Biology, Ludwig-Maximilians-Universität, Menzinger Str. 67, D-80638, München, Germany 31 36, Big Green, Warmington, Peterborough PE8 6TU, United Kingdom 32 Shenzhen Key Laboratory of Southern Subtropical Plant Diversity, Fairylake Botanical Garden, 160 Xianhu Rd., Liantang, Shenzhen 518004, Guangdong, China 33 Department of Biology, School of Life Sciences, East China Normal University, 3663 Zhong Shan North Road, Shanghai 200062, China * Editors Corresponding author: Lars Söderström ([email protected]) Academic editor: Lyubomir Penev | Received 20 June 2015 | Accepted 25 September 2015 | Published 29 January 2016 Citation: Söderström L, Hagborg A, von Konrat M, Bartholomew-Began S, Bell D, Briscoe L, Brown E, Cargill DC, Costa DP, Crandall-Stotler BJ, Cooper ED, Dauphin G, Engel JJ, Feldberg K, Glenny D, Gradstein SR, He X, Heinrichs J, Hentschel J, Ilkiu-Borges AL, Katagiri T, Konstantinova NA, Larraín J, Long DG, Nebel M, Pócs T, Felisa Puche F, Reiner-Drehwald E, Renner MAM, Sass-Gyarmati A, Schäfer-Verwimp A, Moragues JGS, Stotler RE, Sukkharak P, Th iers BM, Uribe J, Váňa J, Villarreal JC, Wigginton M, Zhang L, Zhu R-L (2015) World checklist of hornworts and liverworts. PhytoKeys 59: 1–828. doi: 10.3897/phytokeys.59.6261 Th is checklist is dedicated to Elizabeth Brown and Ray Stotler, who sadly left us during our work with it. “……Charles Darwin wrote of his desire to provide fi nancial support ‘for the formation of a perfect M.S. catalogue of all known plants’ (Darwin 1881, letter 13570). It is a personal embarrassment to me, and should be chastening to us all, that more than 120 years later we still have not delivered on that commitment.” (Crane 2004). Abstract A working checklist of accepted taxa worldwide is vital in achieving the goal of developing an online fl ora of all known plants by 2020 as part of the Global Strategy for Plant Conservation. We here present the fi rst-ever worldwide checklist for liverworts (Marchantiophyta) and hornworts (Anthocerotophyta) that includes 7486 species in 398 genera representing 92 families from the two phyla. Th e checklist has far reaching implications and applications, including providing a valuable tool for taxonomists and systematists, analyzing phytogeographic and diversity patterns, aiding in the assessment of fl oristic and World checklist of hornworts and liverworts 3 taxonomic knowledge, and identifying geographical gaps in our understanding of the global liverwort and hornwort fl ora. Th e checklist is derived from a working data set centralizing nomenclature, taxo- nomy and geography on a global scale. Prior to this eff ort a lack of centralization has been a major impediment for the study and analysis of species richness, conservation and systematic research at both regional and global scales. Th e success of this checklist, initiated in 2008, has been underpinned by its community approach involving taxonomic specialists working towards a consensus on taxonomy, nomenclature and distribution. Keywords Marchantiophyta, Anthocerophyta, nomenclature, taxonomy Introduction Th e natural world is changing fast (Balmford et al. 2005). Th e Global Strategy for Plant Conservation (GSPC) was adopted by the Conference of Parties (COP) of the Convention on Biological Diversity (CBD) in April 2002 (http://www.cbd.int/deci- sion/cop/?id=7183; accessed 2014.06.02). Th e Strategy set out 16 outcome-oriented targets that were to be achieved by 2010. Th e GSPC was designed as a framework for action to halt the loss of plant diversity. Target 1 of the Strategy was to complete “a widely accessible working list of all known plant species, as a step towards a complete world Flora” (Lughadha 2004). As early as 1881 Charles Darwin expressed a wish to have a catalogue of all known plants (Crane 2004). However, over 125 years later, this wish is not yet fulfi lled. Without a working checklist, many of the other objectives in the GSPC cannot be met and botanists around the world cannot communicate about plants on a global basis (Crane 2004). A working list of known plant species is criti- cal for (I) its underpinning role in the eff ective implementation of the other targets through provision of baseline information; (II) increasing the accessibility and use of accurate botanical name information for research, conservation and sustainable use; and (III) real-world politics and how taxonomists respond to the decisions of policy makers (Paton et al. 2008). Version 1.0 of Th e Plant List (http://www.theplantlist.org/) was released in De- cember 2010 aimed to be comprehensive for species of vascular plants (fl owering plants, conifers, ferns and their allies) and of bryophytes (mosses, liverworts and horn- worts), as a response to the 2010 Target 1 of the GSPC and to a clear global need for such data. Th e Plant List is a broad collaboration, coordinated by the Royal Botanic Gardens,