Searching for the sister to sedges (Carex): resolving relationships in the Cariceae‐Dulichieae‐Scirpeae clade (Cyperaceae). (12th August 2014)

• Record Type: Journal Article
• Authors: Léveillé‐Bourret, Étienne; Gilmour, Claire N.; Starr, Julian R.; Naczi, Robert F. C.; Spalink, Daniel; Sytsma, Kenneth J.
• Is Part Of: Botanical journal of the Linnean Society. Volume 176:Number 1(2014:Sep.)
• Page Start: 1
• Page End: 21
• Publication Date: 2014-08-12
• Subjects: Botany -- Periodicals; 580
• DOI: 10.1111/boj.12193
• Languages: English
• ISSNs: 0024-4074

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p>With approximately 2000 species, tribe Cariceae (Cyperaceae) comprises a morphologically distinctive cosmopolitan clade, with holocentric chromosomes (<italic>N</italic> = 6 to 56), complex biogeographical patterns, and habitat diversity ranging from rainforests to deserts. Such a remarkable combination of characteristics should make Cariceae an ideal model for studying the evolution of biodiversity, although they also obscure their relationships in Cyperaceae, complicating attempts to identify the contributing factors to diversity of Cariceae. Recent molecular studies place Cariceae in a strongly supported clade consisting of tribes Dulichieae, Scirpeae <italic>s.s</italic>, and the enigmatic monotypic genus <italic>Khaosokia</italic>, although relationships in this clade are unresolved. Using the plastid genes <italic>matK</italic> and <italic>ndhF</italic> and a greatly improved taxonomic sampling covering 16 of 17 genera and 55% of the species outside Cariceae, our analyses firmly position Dulichieae and <italic>Khaosokia</italic> (79% and 85% bootstrap support) as successive sisters to a clade consisting of five major lineages (<italic>Calliscirpus</italic>, <italic>Trichophorum</italic> + <italic>Oreobolopsis</italic> + <italic>Cypringlea</italic>, Cariceae, <italic>Scirpus</italic> + <italic>Eriophorum</italic>, and <italic>Amphiscirpus</italic> + <italic>Phylloscirpus</italic> + <italic>Zameioscirpus</italic>), the first four of which receive good to strong support (> 80% bootstrap support). Cariceae are sister to the <italic>Trichophorum</italic> clade, although topological tests cannot exclude either <italic>Calliscirpus</italic> or a <italic>Scirpus</italic> clade + <italic>Zameioscirpus</italic> clade as sister to the tribe. <italic>Trichophorum</italic> appears to be paraphyletic and <italic>Eriophorum</italic> is firmly nested in <italic>Scirpus</italic>. There appears to be a trend in the increase of chromosome numbers in <italic>Scirpus</italic> and <italic>Eriophorum</italic> and a trend in the reduction and proliferation of the inflorescence throughout the major Cariceae‐Dulichieae‐Scirpeae clades. © 2014 The Linnean Society of London, <italic>Botanical Journal of the Linnean Society</italic>, 2014, <bold>176</bold>, 1–21.</p> </abstract>