Maximum likelihood and Bayesian analyses of nrDNA (ETS1f) and plastid DNA (rpl32‐trnL, trnH‐psbA) sequence data are presented for ‘C3Cyperus’ (Cyperaceae). The term ‘C3Cyperus’ indicates all species of Cyperus s.l. that use C3 photosynthesis linked with eucyperoid vegetative anatomy. Sampling comprises 77 specimens of 61 different taxa, representing nearly all previously recognized subdivisions of C3Cyperus and the segregate genera Courtoisina, Kyllingiella and Oxycaryum. According to our results, the Cyperus clade is divided in six well‐supported clades. The first of these clades (clade 1) forms three subclades largely corresponding to Cyperus sections Haspani, Incurvi and Diffusi. Clade 2 comprises the entirely New World C. section Luzuloidei sensu Denton (1978). Clade 3 is a highly diverse clade including two subclades: clade 3a, C. sections Pseudanosporum and Anosporum plus the segregate genera Courtoisina and Oxycaryum; and clade 3b, C. section Fusci. Clade 4 corresponds to C. section Alternifolii and clade 5 to C. section Leucocephali plus the segregate genus Kyllingiella. The sixth clade is a well‐supported monophyletic clade encompassing all C4Cyperus s.l. species (‘C4Cyperus’). This study establishes a phylogenetic framework for future studies. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 167, 19–46.
Maximum likelihood and Bayesian inference analyses of nuclear ribosomal DNA (ETS1f) and plastid DNA (rpl32‐trnL, trnH‐psbA) sequence data are presented for ‘C4 Cyperus’ (Cyperaceae). The term ‘C4 Cyperus’ encompasses all species of Cyperus s.l. that use C4 photosynthesis linked with chlorocyperoid vegetative anatomy. Sampling comprises 107 specimens of 104 different taxa, including many of the subdivisions of C4 Cyperus s.s. and all C4 segregate genera (Alinula, Ascolepis, Kyllinga, Lipocarpha, Pycreus, Queenslandiella, Remirea, Sphaerocyperus and Volkiella). According to our results, C4 Cyperus is a well‐supported monophyletic clade nested in C3 Cyperus. Despite the lack of resolution along the backbone of the C4 Cyperus clade and for some internal branches, several well‐supported clades can be distinguished. The first clade in C4 Cyperus is formed by Cyperus cuspidatus and C. waterloti. Other recognizable and well‐supported clades correspond to segregate genera, i.e. Ascolepis, Lipocarpha including Volkiella, and Kyllinga. Species of C4 Cyperus s.s. form a core grade in which the C4 segregate genera are embedded. Pycreus, the largest segregate genus composed of c. 120 species, is not monophyletic as it includes several C4 species of Cyperus s.s. This study establishes a phylogenetic framework for revising the classification and character evolution in Cyperus s.l. © 2013 The Linnean Society of London
Background and aims -Recent molecular studies validate a broad definition of Cyperus (Cyperaceae) uniting genera previously scattered in Cyperoideae. First indication of their affinity with Cyperus was obtained through embryography. Cyperus consists of a paraphyletic C 3 Cyperus and monophyletic C 4 Cyperus. In this study, we aim to check and clarify the putative positions of the segregate genera in C 3 Cyperus. Additional information is given and remarks are made on the position of some as yet unplaced species or sections in the C 3 Cyperus phylogeny. Methods -Embryos of Cyperus constanzae and C. gardneri were cleared and drawn. Inflorescences of selected C 3 Cyperus species were investigated using scanning electron and light microscopy. Histochemical tests were performed to assess the presence of suberin in the 'corky' tissue of the nutlets of Cyperus pectinatus. Key results -Embryography not only supports tribal classification in Cyperoideae, it is also phylogenetically informative in C 3 Cyperus. Morphology and ontogeny support molecular phylogenetic results suggesting the inclusion of the segregate genera in C 3 Cyperus as new sections or in established sections, and confirm the need to broaden the circumscription of some of these sections. Conclusion -Although less diverse than C 4 Cyperus, C 3 Cyperus includes clades which evolved an exceptional morphological diversity compared to its limited species numbers. The segregate genera Courtoisina (deciduous spikelets), Kyllingiella (spirally-arranged glumes) and Oxycaryum (spirallyarranged glumes and dorsiventrally flattened dimerous gynoecia), and the taxon Anosporum (recognised at sectional, subgeneric or generic level) are here included in C 3 Cyperus (= Cyperus subg. Anosporum) as sections or included in an existing section (Kyllingiella is included in Cyperus sect. Leucocephali). A formal taxonomic revision is presented with relevant new names and combinations, synonyms, diagnoses and identification keys.
Background and aims -In Cyperaceae, the single-ovuled, usually triangular gynoecia are widely considered to have a basic number of three carpels, often reduced to two, resulting in dimerous pistils. However, laterally flattened dimerous pistils cannot be explained by any existing carpel reduction theories, because a single stigma in median position replaces the two adaxial stigmata. This paper presents a comparative study of the ontogenetic and anatomical adaptations facilitating the origin of new pistil forms in Cyperoideae, focusing on modified gynoecia. It includes a re-evaluation of Blaser's (1941) anatomical studies in Cyperaceae. We aim to test Blaser's hypothesis that is based on an acropetal developmental model of the floral vasculature and the general Cyperoid ontogenetic model of Vrijdaghs et al. (2009), which states that cyperoid ovaries originate from an annular primordium. Methods -SEM, dark field and phase contrast microscopy. Key Results -All cyperoid pistils studied develop according to a cyperoid floral ontogenetic pattern, in which carpel primordia are congenitally fused. In Pycreus sanguinolentus (and other species), separate procambial initiation zones were observed in both the flower receptacle and separate floral primordia, which connect (or not) at later developmental stages. Conclusions -The presence of an annular ovary primordium instead of individual carpel primordia, combined with the bidirectional development of the pistil vasculature liberate the developing gynoecium from the structural constraints proper to a typical carpellate organisation. Procambial initiation zones in the receptacular vascular plexus and in individual floral primordia constitute the basis for the formation of a flexible vascular system in cyperoid flowers. Moreover the development of the ovary and ovule are decoupled. Consequently, in Cyperoideae the acquired developmental freedom of the pistil resulted in various adaptations. Genus Model (fig. 3) Bolboschoenus (Asch.) Palla (as Scirpus L.) A1/B1 Carex L. A2/B2 Cyperus L. A2 Dulichium Pers. C1 Eleocharis R.Br. (as Heleocharis T.Lestib.) A2/C2 Eriophorum L. A1 Fimbristylis Vahl A2/B2 Lipocarpha R.Br. A2/B2 Pycreus P. Beauv. (as Cyperus L.) D1 Rhynchospora Vahl B1/B2/C1/C2 Schoenoplectus (Rchb.) Palla (as Scirpus L.) A1/B1
The sedge genera Alinula, Ascolepis, Kyllinga, Lipocarpha, Pycreus, Queenslandiella, Remirea, Sphaerocyperus and Volkiella (Cyperaceae) were recognised at generic level because they possess specialised inflorescence and/or flower characters. However, recent molecular phylogenetic analyses show that these genera are all nested in a paraphyletic Cyperus s.s. and therefore should be viewed as part of a broadly circumscribed genus Cyperus. For all species of Alinula and for the single species of Queenslandiella, Remirea and Sphaerocyperus, Cyperus names were already published by other authors. For the species of Lipocarpha and Volkiella, Cyperus names and a new sectional classification are published in a separate paper including a detailed molecular phylogenetic hypothesis for these taxa. Based on a study of herbarium specimens and literature, in this paper, twenty species of Ascolepis, seventeen species of Kyllinga, and six species of Pycreus, which do not yet have a validly published and legitimate name in Cyperus, are formally included into Cyperus as new combinations or new names. Notes on the synonymy of an African Pycreus species are also included.
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