J Syst Evol ›› 2021, Vol. 59 ›› Issue (4): 726-762.DOI: 10.1111/jse.12722

• Research Articles • Previous Articles     Next Articles

A framework infrageneric classification of Carex (Cyperaceae) and its organizing principles

Global Carex Group, Eric H. Roalson1*, Pedro Jiménez‐Mejías2,3*, Andrew L. Hipp4*, Carmen Benítez‐Benítez5, Leo P. Bruederle6, Kyong‐Sook Chung7, Marcial Escudero8, Bruce A. Ford9, Kerry Ford10, Sebastian Gebauer11, Berit Gehrke12, Marlene Hahn4, Muhammad Qasim Hayat13, Mathias H. Hoffmann11, Xiao‐Feng Jin14, Sangtae Kim15, Isabel Larridon16,17, Étienne Léveillé‐Bourret18, Yi‐ Fei Lu19, Modesto Luceño5, Enrique Maguilla8, Jose Ignacio Márquez‐Corro5, Santiago Martín‐Bravo5, Tomomi Masaki20, Mónica Míguez5, Robert F. C. Naczi21, Anton A. Reznicek22, Daniel Spalink23, Julian R. Starr24, Uzma13, Tamara Villaverde25, Marcia J. Waterway26, Karen L. Wilson27, and Shu‐Ren Zhang28   

  1. 1School of Biological Sciences, Washington State University, Pullman, Washington, DC 99164‐4236, USA
    2Departamento de Biología (Botánica), Facultad de Ciencias Biológicas, Universidad Autónoma de Madrid, c/Darwin 2 Madrid 28049, Spain
    3Centro de Investigación en Biodiversidad y Cambio Global (CIBC‐UAM), Universidad Autónoma de Madrid, Madrid 28049, Spain
    4The Morton Arboretum, 4100 Illinois Route 53 Lisle, IL 60532, USA
    5Department of Molecular Biology and Biochemical Engineering, Universidad Pablo de Olavide, Sevilla 41013, Spain
    6Department of Integrative Biology, University of Colorado Denver, Denver, CO 80217‐3364, USA
    7Jungwon University, Goesan, Chungbuk, South Korea
    8Departamento de Biología Vegetal y Ecología, Área de Botánica, Facultad de Biología, Universidad de Sevilla, Sevilla 41012, Spain
    9Department of Biological Sciences, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
    10Allan Herbarium, Manaaki‐Whenua Landcare Research, PO Box 69040 Lincoln, Canterbury 7640, New Zealand
    11Department of Systematic Botany, Martin Luther University Halle‐Wittenberg Geobotany and Botanical Garden, Halle (Saale) D‐06108, Germany
    12Johannes Gutenberg University of Mainz, Mainz D‐55122, Germany
    13Plant Systematics and Evolution Laboratory, Department of Plant Biotechnology, Atta‐Ur‐Rahman School of Applied Biosciences (ASAB), National University of Sciences and Technology (NUST), Islamabad, Pakistan
    14College of Life and Environment Sciences, Hangzhou Normal University, Hangzhou 311121, China
    15Department of Biology, Sungshin Women's University, Seoul 01133, South Korea
    16Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AE, United Kingdom
    17Systematic and Evolutionary Botany Lab, Department of Biology, Ghent University, K.L. Ledeganckstraat 35 Gent 9000, Belgium
    18Département de Sciences Biologiques, Institut de Recherche en Biologie Végétale de I'Université de Montréal, 4101 Sherbrooke East Montréal, Quebec H1X 2B2, Canada
    19College of Life Sciences, Zhejiang University, Hangzhou 310058, China
    20Department of Biosphere‐Geosphere Science, Faculty of Biosphere‐Geosphere Science, Okayama University of Science, Okayama 700‐0005, Japan
    21New York Botanical Garden, Bronx, NY 10458, USA
    22University of Michigan Herbarium, Ann Arbor, MI 48108, USA
    23Department of Ecosystem Science & Management, Texas A&M University, College Station, TX 77843, USA
    24Department of Biology, University of Ottawa, Gendron Hall, Room 160, 30 Marie Curie Ottawa, Ontario K1N 6N5, Canada
    25Departamento de Biología y Geología, Universidad de Almería, Ctra. Sacramento s/n Almería 04120, Spain
    26Plant Science Department, McGill University, Ste‐Anne‐de‐Bellevue, Quebec H9X 3V9, Canada
    27National Herbarium New South Wales, Sydney, New South Wales, Australia
    28Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
  • Received:2020-08-31 Accepted:2020-12-23 Online:2020-12-28 Published:2021-07-01

Abstract: Phylogenetic studies of Carex L. (Cyperaceae) have consistently demonstrated that most subgenera and sections are para- or polyphyletic. Yet, taxonomists continue to use subgenera and sections in Carex classification. Why? The Global Carex Group (GCG) here takes the position that the historical and continued use of subgenera and sections serves to (i) organize our understanding of lineages in Carex, (ii) create an identification mechanism to break the ~2000 species of Carex into manageable groups and stimulate its study, and (iii) provide a framework to recognize morphologically diagnosable lineages within Carex. Unfortunately, the current understanding of phylogenetic relationships in Carex is not yet sufficient for a global reclassification of the genus within a Linnean infrageneric (sectional) framework. Rather than leaving Carex classification in its current state, which is misleading and confusing, we here take the intermediate steps of implementing the recently revised subgeneric classification and using a combination of informally named clades and formally named sections to reflect the current state of our knowledge. This hybrid classification framework is presented in an order corresponding to a linear arrangement of the clades on a ladderized phylogeny, largely based on the recent phylogenies published by the GCG. It organizes Carex into six subgenera, which are, in turn, subdivided into 62 formally named Linnean sections plus 49 informal groups. This framework will serve as a roadmap for research on Carex phylogeny, enabling further development of a complete reclassification by presenting relevant morphological and geographical information on clades where possible and standardizing the use of formal sectional names.

Key words: Carex, clades, classification, sections, subgenera