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

Roalson, Eric H.; Jiménez‐Mejías, Pedro; Hipp, Andrew L.; Benítez‐Benítez, Carmen; Bruederle, Leo P.; Chung, Kyong‐Sook; Escudero, Marcial; Ford, Bruce A.; Ford, Kerry; Gebauer, Sebastian; Gehrke, Berit; Hahn, Marlene; Hayat, Muhammad Qasim; Hoffmann, Mathias H.; Jin, Xiao‐Feng; Kim, Sangtae; Larridon, Isabel; Léveillé‐Bourret, Étienne; Lu, Yi‐Fei; Luceño, Modesto

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

Resource type

Journal article

Creator (person)

Roalson, Eric H.

ORCID

Jiménez‐Mejías, Pedro

ORCID

Hipp, Andrew L.

Benítez‐Benítez, Carmen

ORCID

Bruederle, Leo P.

Chung, Kyong‐Sook

Escudero, Marcial

Ford, Bruce A.

Ford, Kerry

ORCID

Gebauer, Sebastian

Gehrke, Berit

Hahn, Marlene

Hayat, Muhammad Qasim

Hoffmann, Mathias H.

ORCID

Jin, Xiao‐Feng

Kim, Sangtae

Larridon, Isabel

Léveillé‐Bourret, Étienne

ORCID

Lu, Yi‐Fei

Luceño, Modesto

Maguilla, Enrique

Márquez‐Corro, Jose Ignacio

ORCID

Martín‐Bravo, Santiago

ORCID

Masaki, Tomomi

Míguez, Mónica

Naczi, Robert F. C.

Reznicek, Anton A.

Spalink, Daniel

Starr, Julian R.

Uzma

ORCID

Villaverde, Tamara

ORCID

Waterway, Marcia J.

Wilson, Karen L.

Zhang, Shuren

Date published

December 28, 2020

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 here takes the position that the historical and continued use of subgenera and sections serves to (1) organize our understanding of lineages in Carex, (2) create an identification mechanism to break the ~2000 species of Carex into manageable groups and stimulate its study, and (3) provide a framework to recognize morphologically diagnosable lineages within Carex. Unfortunately, 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 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.