The Botanical Review

, Volume 75, Issue 1, pp 2–21

Phylogeny of Cyperaceae Based on DNA Sequence Data: Current Progress and Future Prospects

  • A. Muthama Muasya
  • David A. Simpson
  • G. Anthony Verboom
  • Paul Goetghebeur
  • Robert F. C. Naczi
  • Mark W. Chase
  • Erik Smets
Open AccessArticle

DOI: 10.1007/s12229-008-9019-3

Cite this article as:
Muasya, A.M., Simpson, D.A., Verboom, G.A. et al. Bot. Rev (2009) 75: 2. doi:10.1007/s12229-008-9019-3

Abstract

In the last decade, efforts to reconstruct suprageneric phylogeny of the Cyperaceae have intensified. We present an analysis of 262 taxa representing 93 genera in 15 tribes, sequenced for the plastid rbcL and trnL-F (intron and intergenic spacer). Cyperaceae are monophyletic and resolved into two clades, here recognised as Mapanioideae and Cyperoideae, and the overall topology is similar to results from previous studies. Within Cyperoideae, Trilepideae are sister to rest of taxa whereas Cryptangieae, Bisboeckelerieae and Sclerieae are resolved within Schoeneae. Cladium and Rhynchospora (and Pleurostachys) are resolved into clades sister to the rest of Schoeneae, lending support to the recognition of these taxa in separate tribes. However, we retain these taxa in Schoeneae pending broader sampling of the group. The phylogenetic position of 40 species in 21 genera is presented in this study for the first time, elucidating their position in Abildgaardieae (Trachystylis), Cryptangieae (Didymiandrum, Exochogyne), Cypereae (Androtrichum, Volkiella), Eleocharideae (Chillania), and Schoeneae (Calyptrocarya, Morelotia). More sampling effort (more taxa and the use of more rapidly evolving markers) is needed to resolve relationships in Fuireneae and Schoeneae.

Keywords

Suprageneric ClassificationMapanioideaeCyperioideaeTribal CircumscriptionsrbcLtrnL-F

Introduction

Cyperaceae comprise 109 genera and approximately 5,500 species and have an almost cosmopolitan distribution (Govaerts et al., 2007). About 35% of the genera are monotypic, 26% have two to five species, and there are a seven (6%) genera with over 200 species, the largest being Cyperus (686 species) and Carex (1,757 species; Goetghebeur, 1998). The family shows extreme reduction in floral morphology, and the majority of the smaller genera are carved out of the larger ones on the basis on one or few distinguishing features.

Family level phylogenetic studies in the last ten years have used morphological (e.g. Simpson, 1995; Bruhl, 1995; Goetghebeur, 1998), molecular (e.g. Muasya et al., 1998; Simpson et al., in press), and combined morphological and molecular data (Muasya et al., 2000b). The two most recent classifications based on morphological data (including gross morphology, anatomy and embryology) differ in suprageneric groupings of tribes and subfamilies. Bruhl (1995) recognised two subfamilies, Cyperoideae and Caricoideae, whereas Goetghebeur (1998) recognised two additional subfamilies, Sclerioideae and Mapanioideae, both of which were included in Caricoideae by Bruhl (1995). The treatments also differed in tribal circumscription, with Bruhl (1995) recognising 12 tribes and treating Scirpeae broadly to include taxa classified in tribes Dulicheae, Fuireneae, Eleocharideae and Cypereae sensu Goetghebeur (1998).

Molecular DNA sequence data are increasingly used in angiosperm classification. In Cyperaceae, broad suprageneric studies have so far sampled all subfamilies and tribes, but sampling effort is not evenly distributed among all tribes. Family-level studies have been based mainly on rbcL sequence data (e.g. Muasya et al., 1998; Simpson et al., 2007), whereas at tribal or subfamilial levels other plastid and nuclear regions have been used. The plastid regions rps16 intron, trnL intron and trnL-F intergenic spacer have been used in studies of subfamily Mapanioideae (e.g. Simpson et al., 2003) and a number of studies at tribal and generic level.

This study uses three of the most commonly used plastid regions (the rbcL gene, the trnL intron, and the trnL-F spacer) to reconstruct relationships of the family and presents an overview of the current status of suprageneric phylogenetic studies. The rbcL gene has been sequenced for over 60% genera of Cyperaceae (e.g. Simpson et al., 2007) and can be aligned unambiguously, whereas trnL-F (both the trnL intron and the trnl-F intergenic spacer) has been used to a greater extent in generic studies and is more difficult to align at the family level.

Analysis of rbcL and trnl-F Data

The analysis includes a total 262 taxa (258 species) of Cyperaceae in 93 genera from the 15 tribes and four subfamilies recognised by Goetghebeur (1998). Sequences from previous studies (Bremer, 2002; Dhooge et al., 2003; Muasya et al., 1998, 2000a, 2000b, 2001, 2002; Simpson et al., 2003, 2007; Verboom, 2006; Zhang et al., 2004) were analysed together with 41 newly sequenced taxa representing 22 genera, nine of which had not been previously sequenced. Total DNA was extracted from vegetative material (leaves or culms) collected in the field or from herbarium specimens (Table 1). DNA extraction, amplification and sequencing were performed according to published procedures (e.g. Muasya et al., 2002); the resulting sequences were aligned manually and are lodged with GenBank (Table 1).
Table 1

List of Taxa Sampled with vouchers and Genbank Accession Numbers. Classification Following Interpretation of Current Data and Goetghebeur (1998)

Taxon

Voucher

GenBank accession numbers

rbcL

trnL-F OR intron/spacer

Cyperoideae Suess.

Abildgaardieae Lye

   

 Abildgaardia ovata (Burm. f.) Kral

Kenya: Muasya et al. 684 (EA, K)

Y12985

AJ295754

 Actinoschoenus repens Raynal

Zambia: Robinson 3643 (K)

EF178537

 

 Arthrostylis aphylla R. Br.

Australia: Wilson 8249 (NSW)

AY725939

 

 Bulbostylis atrosanguinea (Boeck.) C. B. Clarke

Kenya: Muasya 1037 (EA, K)

Y12992

 

 Bulbostylis hispidula (Vahl) R. W. Haines

Kenya: Muasya 1025 (EA, K)

Y12944

 

 Crosslandia setifolia W. Fitzg.

Australia: Wilson 10147 (K)

EF178538

EF178592

 Fimbristylis complanata (Retz.) Link

Kenya: Muasya 1029 (EA, K)

Y13009

 

 Fimbristylis dichotoma (L.) Vahl

Kenya: Muasya 1006 (EA, K)

Y13008

AJ295755

 Nemum spadiceum (Lam.) Desv. ex Ham.

WEST AFRICA: Baldwin 9766 (K)

Y12945

 

 Trachystylis stradbrokensis (Domin) Kük.

Australia: Wilson 8175 (K)

EF178539

EF178591

Bisboeckelereae Pax ex L.T. Eiten

   

 Becquerelia cymosa Brongn.

Brazil: Thomas et al. 10284 (NY)

Y12948

 

 Calyptrocarya bicolor (H. Pfeiff.) Koyama

RBGKEW DNA 10389

EF178540

 

 Diplacrum africanum C. B. Clarke

Tanzania: Vollensen 3967 (K)

AY725942

 

Cariceae Kunth ex Dumort.

   

 Carex cephalophora Muhl. ex Willd.

Kress et al. (2005)

DQ006089

 

 Carex conferta A. Rich.

Kenya: Muasya 1055 (K)

Y12999

 

 Carex echinochloe Kunze

Kenya: Muasya 1051 (K)

Y12997

AF191818

 Carex hostiana DC.

Chase et al. (1993)

L12672

 

 Carex monostachya A. Rich.

Kenya: Muasya 1052 (K)

Y12998

 

 Carex sylvatica Huds.

Simpson et al. (2003)

 

AY344175

 Kobresia simpliciuscula (Wahlenb.) Mackenzie

Plunkett et al. (1995); Yen et al. (2000)

U49232

AF164948

 Uncinia nemoralis K. L. Wilson

Australia: Wilson et al. 9533 (K)

AY725956

 

 Schoenoxiphium ecklonii Nees

S. Africa: Williams 968 (K)

EF178541

 

 Schoenoxiphium lehmannii (Nees) Kunth ex Steud.

Tanzania: J M G 94/94 (K)

EF178542

 

 Schoenoxiphium sparteum (Wahlenb.) C.B.Clarke

Kenya: Muasya 2566 (EA)

EF178543

 

Uncertain tribe aff. Cariceae

   

 Khaosokia caricoides D.A.Simpson, Chayam. & J.Parn.

Thailand: Simpson et al. 1886 (K)

AY725948

EF178535

Cryptangieae Benth.

   

 Didymiandrum stellatum (Boeck.) Gilly

Venezuela: Liesner 23562 (GENT)

EF178544

 

 Exochogyne amazonica C. B. Clarke

Brazil: Aparecida da Silva 1986 (GENT)

EF178545

 

 Lagenocarpus alboniger (A. St.-Hil.) C. B. Clarke

Brazil: Thomas 11111 (NY)

AY725949

 

Cypereae Dumort.

   

 Alinula paradoxa Goetgh. & Vorster

Tanzania: Faden et al. 96/29 (K)

AJ278290

AJ295756

 Androtrichum giganteum (Kunth) H. Pfeiff.

Argentina: Tressens et al. 4292 (K)

EF178546

 

 Androtrichum trigynum (Spreng.) H. Pfeiff.

Argentina: Goetghebeur 4764 (GENT)

EF178547

 

 Ascolepis capensis (Kunth) Ridl.

Kenya: Muasya 1009 (EA, K)

Y13003

AJ295757

 Ascolepis protea Welw.

Congo: Fay 2700 (K)

Y13002

 

 Courtoisina assimilis (Steud.) Maquet

Tanzania: Faden et al. 96/119 (K)

AY40590

AY040595

 Cyperus compressus L.

Thailand: Muasya 1375 (K)

AF449506

AF449555/

 Cyperus congestus Vahl

Australia: Coveny et al. 17492 (K)

AF449507

AF449556/ AF449568

 Cyperus cuspidatus Kunth

Thailand: Muasya 1374 (K)

AF449508

AF449557/ AF449569

 Cyperus cyperoides (L.) Kuntze

Thailand: Muasya 1277 (K)

AF449509

AF449558/ AF449570

 Cyperus dichroostachyus A. Rich.

Kenya: Muasya 976 (EA, K)

Y12965

/AF449571

 Cyperus endlichii Kük.

Kenya: Muasya 695 (K)

AF449510

AF449559/ 449572

 Cyperus involucratus Rottb.

Madagascar: Kew Acc. 6136603

Y12967

AJ295758

 Cyperus kerstenii Boeck.

Kenya: Muasya 984 (EA, K)

Y13018

AY040597

 Cyperus laevigatus L.

Kenya: Muasya 1041 (EA)

Y13017

AY040596

 Cyperus longus L.

Europe: Chase 2276 (K)

Y13015

AY040598

 Cyperus meeboldii Kük.

Kenya: Muasya 1255 (EA, K)

AF449511

AF449560/

 Cyperus papyrus L.

Chad: Hepper 4213 (K)

Y12966

AJ295759

 Cyperus plateilema (Steud.) Kük.

Kenya: Muasya 969 (EA, K)

AF449512

AF449561/ AF449573

 Cyperus pseudovestitus (C. B. Clarke) Kük.

Kenya: Muasya 1268 (K)

AF449513

AF449562/ AF449574

 Cyperus pulchellus R. Br.

Thailand: Muasya 1377 (K)

AY40591

AY040599

 Cyperus pygmaeus Rottb.

Kenya: Muasya 1133 (K)

AJ404698

AJ295760

 Cyperus rigidifolius Steud.

Kenya: Muasya 1031 (K)

Y13016

AY040600

 Desmoschoenus spiralis Hook. f.

New Zealand: Ford 44/94 (NU)

AJ404701

AJ295753

 Ficinia bergiana Kunth

S. Africa: Muasya 2337 (BOL)

EF200588

EF178593

 Ficinia distans C. B. Clarke

S. Africa: Muasya 2283 (BOL)

EF178548

EF178594

 Ficinia esterhuyseniae Muasya

S. Africa: Muasya 2312 (BOL)

EF178549

EF178590

 Ficinia gracilis Schrad.

S. Africa: Muasya 2355

EF178589

EF178595

 Ficinia gracilis Schrad.

Tanzania: Faden et al. 96/433 (K)

EF178550

EF178534

 Ficinia gydomontana T. H. Arnold & K. D. Gordon-Gray

S. Africa: Muasya 2333 (BOL)

EF178551

EF178596

 Ficinia indica (Lam.) H. Pfeiff.

S. Africa: Muasya 2318 (BOL)

EF178552

EF178597

 Ficinia laciniata (Thunb.) Nees

S. Africa: Muasya 2340 (BOL)

EF178553

EF178598

 Ficinia nodosa (Rottb.) Goetgh., Muasya & D. A. Simpson

Australia: Strind 21216 (K)

Y12984

AJ295793

 Ficinia paradoxa (Schrad.) Nees

S. Africa: Verboom 534 (BOL)

DQ058354

DQ058317

 Ficinia pinguior C. B. Clarke

S. Africa: Muasya 1183 (K)

AJ404703

AJ295772

 Ficinia polystachya Levyns

S. Africa: Muasya 2330 (K)

EF178554

EF178599

 Ficinia ramosissima Kunth

S. Africa: Muasya 2288 (K)

EF178555

EF178600

 Ficinia repens Kunth

S. Africa: Muasya 2347 (K)

EF178556

EF178601

 Ficinia rigida Levyns

S. Africa: Muasya 2319 (K)

EF178557

EF178602

 Ficinia trichodes (Schrad.) Benth. & Hook. f.

S. Africa: Muasya 2328 (K)

EF178558

EF178603

 Ficinia tristachya (Rottb.) Nees

S. Africa: Muasya 1233 (K)

AJ404702

AJ295771

 Hellmuthia membranacea (Thunb.) R. W. Haines & Lye

S. Africa: Weerderman et al. 269 (K); Muasya 1145 (K)

Y13000

AJ295815

 Isolepis aucklandica Hook. f.

Australia: Wilson et al. 9462 (K)

AJ404704

AJ295773

 Isolepis bicolor Carmich.

Tristan Da Cunha: Richardson 105 (K)

AJ404705

AJ295774

 Isolepis cernua (Vahl) Roem. & Schult. var. cernua

Britain: Muasya 1058 (K)

Y13014

AJ295775

 Isolepis cernua var. meruensis (Lye) Muasya

Tanzania: Muasya 1061 (K)

AJ404715

AJ295791

 Isolepis cernua var. platycarpa (S. T. Blake) Muasya

Australia: Coveny et al. 17465 (K)

AJ404716

AJ295794

 Isolepis cernua var. setiformis (Benth.) Muasya

S. Africa: Muasya 1194 (K)

AJ404725

AJ295805

 Isolepis costata A. Rich.

Kenya: Muasya 1049 (EA, K)

Y12981

AJ295776

 Isolepis crassiuscula Hook. f.

Australia: Coveny et al. 17478 (K)

AJ404706

AJ295777

 Isolepis diabolica (Steud.) Schrad.

S. Africa: Muasya 1163 (K)

AJ404707

AJ295778

 Isolepis digitata Nees ex Schrad.

S. Africa: Muasya 1230 (K)

AJ404708

AJ295779

 Isolepis fluitans (L.) R. Br.

Kenya: Muasya 1057 (K)

Y12961

AJ295780

 Isolepis gaudichaudiana Kunth

Australia: Coveny et al. 17476 (K)

AJ404709

AJ295781

 Isolepis graminoides (R. W. Haines & Lye) Lye

Kenya: Muasya 986 (EA, K)

Y12960

AJ295782

 Isolepis habra (Edgar) Soják

Australia: Coveny et al. 17477 (NSW)

AJ404710

AJ295783

 Isolepis hystrix (Thunb.) Nees

S. Africa: Muasya 1150 (K)

AJ404711

AJ295785

 Isolepis inundata R. Br.

Australia: Wilson et al. 9461 (NSW)

AJ404712

AJ295786

 Isolepis inyangensis Muasya & Goetgh.

Zimbabwe: Muasya et al. 1125 (K)

AJ297506

AJ295787

 Isolepis keniaensis Lye

Kenya: Cabolt plant ‘A’ (K)

Y12980

AJ295788

 Isolepis levynsiana Muasya & D. A. Simpson

S. Africa: Muasya 1151 (K)

AF449514

AF449563/ AF449575

 Isolepis ludwigii (Steud.) Kunth

S. Africa: Muasya 1181 (K)

AJ404713

AJ295789

 Isolepis marginata (Thunb.) A. Dietr.

Australia: Coveny et al. 17452 (K)

AJ404714

AJ295790

 Isolepis montivaga (S. T. Blake) K.L.Wilson

Australia: Wilson et al. 9480 (K)

AJ297507

AJ295792

 Isolepis pellocolea B. L. Burtt

Lesotho: Gordon-Gray 49694 (NU)

AJ404729

AJ297514

 Isolepis producta (C. B. Clarke) K. L. Wilson

Australia: Wilson et al. 9510 (K)

AJ404717

AJ295795

 Isolepis prolifera (Rottb.) R. Br.

Australia: Coveny et al. 17487 (K)

AJ404718

AJ295796

 Isolepis rubicunda (Nees) Kunth

S. Africa: Muasya 1221 (K)

AJ404719

AJ295797

 Isolepis sepulcralis Steud.

Australia: Coveny et al. 17456 (K)

AJ404720

AJ295798

 Isolepis setacea (L.) R. Br.

Kenya: Muasya 1059 (K)

Y12962

AJ295799

 Isolepis striata (Nees) Kunth

S. Africa: Muasya 1141 (K)

AJ404721

AJ295801

 Isolepis subtillisima Boeck.

Australia: Coveny et al. 17474 (K)

AJ297508

AJ295800

 Isolepis sulcata (Thouars) Carmich.

Tristan Da Cunha: Richardson 80 (K)

AJ404722

AJ295802

 Isolepis tenuissima (Nees) Kunth

S. Africa: Muasya 2369 (K)

AY725947

 

 Isolepis varians Steud.

Chile: Pisano 259 (K)

AJ404723

AJ295803

 Isolepis venustula Kunth

S. Africa: Muasya 1189 (K)

AJ404724

AJ295804

 Isolepis wakefieldiana (S. T. Blake) K. L. Wilson

Australia: Neish et al. 110 (K)

AJ404726

AJ295806

 Kyllinga appendiculata K. Schum.

Kenya: Muasya 1050 (EA, K)

Y13007

AJ295761

 Kyllinga brevifolia Rottb.

Australia: Coveny et al. 17459 (K)

AF449515

AF449564/ AF449576

 Kyllinga bulbosa P. Beauv.

Kenya: Muasya 1020 (EA, K)

Y12979

AY040601

 Kyllingiella microcephala (Steud.) R. W. Haines & Lye

Zimbabwe: Muasya et al. 1118 (K)

AY040592

AJ295807

 Kyllingiella polyphylla (A. Rich.) Lye

Tanzania: Wingfield 497 (K)

Y13013

AJ295515

 Lipocarpha hemisphaerica (Roth.) Goetgh.

Thailand: Muasya 1217 (K)

AF449516

AF449565/ AF449577

 Lipocarpha microcephala (R. Br.) Kunth

Australia: Wilson et al. 3383 (K)

Y12991

 

 Lipocarpha nana (A.Rich.) J. Raynal

Kenya: Muasya 972 (EA, K)

Y12990

AJ295762

 Oxycaryum cubense (Poepp. & Kunth) E. Palla

Zambia: Richards 13318 (K)

Y13006

AY040602

 Pycreus flavescens (L.) Rchb.

Kenya: Muasya 1022 (EA, K)

Y13005

AJ295763

 Pycreus mundtii Nees

Thailand: Muasya 1464 (K)

AF449517

AF449566/ AF449578

 Pycreus nuerensis (Boeck.) S. S. Hooper

Tanzania: Muasya 940 (EA, K)

Y13004

AY040603

 Pycreus sanguinolentus (Vahl) Nees

Australia: Coveny et al. 17461 (K)

 

AF449567/ AF449579

 Queenslandiella hyalina (Vahl) Ballard

Kenya: Mwachala 296 (EA)

AY725953

 

 Remirea maritima Aubl.

Tanzania: Faden et al. 96/48 (K)

AY040593

AY040604

 Scirpoides burkei (C. B. Clarke) Goetgh., Muasya & D. A. Simpson

S. Africa: Hargreaves 3361 (K)

Y13001

AJ295810

 Scirpoides holoschoenus (L.) Soják

S. Africa: Acocks s.n. (K)

Y12994

AJ295811

 Scirpoides thunbergii (Schrad.) Soják

S. Africa: Muasya 1205 (K)

AJ404727

AJ295812

 Scirpus falsus C. B. Clarke

S. Africa: Hilliard 13609 (GENT)

EF178559

 

 Scirpus ficinioides Kunth

S. Africa: Hilliard 16095 (GENT)

EF178560

 

 Sphaerocyperus erinaceus (Ridl.) Lye

Tanzania: Faden et al. 96/338 (K)

AJ404699

AJ295764

 Volkiella disticha Merxm. & Czech

Namibia: Muller et al. 4245 (K)

EF178561

 

Dulicheae Rchb. ex J. Schultze-Motel

   

 Blysmus compressus Panz.

Afghanistan: Dobson 221 (K)

AJ404700

AJ295766

 Dulichium arundinaceum (L.) Britton

USA: Goetghebeur 9914 (GENT); Roalson et al. (2001)

AY725943

AF285067

Eleocharideae Goetgh.

   

 Chillania pusilla Roiv.

Chile: Grau 1433 (GENT)

EF178562

 

 Eleocharis atropurpurea (Retz.) Presl

Kenya: Muasya et al. 752 (EA, K)

Y13012

 

 Eleocharis gracilis R.Br.

Australia: Wilson et al. 9462 (K)

EF178563

 

 Eleocharis marginulata Steud.

Kenya: Muasya 1039 (EA, K)

Y13011

AJ295768

 Eleocharis pauciflora (Lightf.) Link.

USA: Mastrogiuseppe 7461 (WS)

U49229

 

Fuireneae Reichenb. ex Fenzl

   

 Actinoscirpus grossus (L. f.) Goetgh. & D. A. Simpson

Malaysia: Simpson 2660 (K)

Y12953

AJ295765

 Bolboschoenus caldwellii (V. Cook) Soják

Australia: Wilson et al. 9530 (K)

EF178564

 

 Bolboschoenus maritimus (L.) Palla

Botswana: Smith 2452 (K)

Y12996

AJ295767

 Bolboschoenus nobilis (Ridl.) Goetgh. & D. A. Simpson

S. Africa: Leistner 144 (K)

Y12995

 

 Fuirena abnormalis C. B. Clarke

Tanzania: Faden et al. 96/118 (K)

EF178565

 

 Fuirena ciliaris (L.) Roxb.

Tanzania: Muasya 951 (EA, K)

Y12971

 

 Fuirena coerulescens Steud.

S. Africa: Muasya 2322 (K)

EF178566

 

 Fuirena hirsuta (Berger) P. L. Forbes

S. Africa: Muasya 2324 (K)

EF178567

 

 Fuirena welwitschii Ridl.

Kenya: Muasya 1024 (EA, K)

Y12993

EF178605

 Fuirena sp.

Brazil: Thomas et al. 10404 (NY)

Y12970

 

 Isolepis humillima (Benth.) K. L. Wilson

Australia: Thomas et al. 622 (BRI)

AJ404728

AJ295784

 Schoenoplectiella articulata (L.) Lye

Tanzania: Muasya 947 (EA, K)

Y12987

 

 Schoenoplectiella juncea (Willd.) Lye

Kenya: Muasya et al. 775 (K)

Y12952

 

 Schoenoplectiella senegalensis (Hochst. ex A. Rich.) Lye

Kenya: Muasya et al. 2440 (EA)

EF178568

EF178606

 Schoenoplectus confusus (N. E. Br.) Lye

Kenya: Muasya et al. 2438 (EA)

EF178569

 

 Schoenoplectus corymbosus (Roth ex Roem. & Schult.) J. Raynal

Kenya: Muasya 1004 (EA)

EF178570

EF178607

 Schoenoplectus lacustris (L.) Palla

Britain: Muasya 1043 (K)

Y12943

AJ295809

 Schoenoplectus litoralis (Schrad.) Palla

Hong Kong: Shaw 883 (K)

EF178571

 

 Schoenoplectus mucronatus (L.) Palla

Thailand: Muasya et al. 1290 (K)

EF178572

 

 Scirpus varius Boeck. ex C.B.Clarke

Botswana: Smith 5376 (NU)

EF178573

 

Rhynchosporeae

   

 Pleurostachys sp.

Brazil: Kallunki et al. 513 (NY)

Y12989

 

 Rhynchospora alba (L.) Vahl

Simpson et al. (2003)

 

AY344174

 Rhynchospora brownii Roem. et Schult.

S. Africa: Verboom 616 (BOL)

DQ058353

DQ058316

 Rhynchospora fascicularis (Michx.) Vahl

Plunkett et al. (1995)

U49233

 

 Rhynchospora nervosa (Vahl.) Boeck.

Brazil: Kallunki et al. 512 (NY)

Y12977

 

Schoeneae Dumort.

   

 Baumea rubiginosa (Spreng.) Boeck.

Australia: Wilson et al. 9471 (K)

AY725940

 

 Capeobolus brevicaulis (C. B. Clarke) J. Browning

S. Africa: Verboom 646, BOL

DQ058343

DQ058303

 Carpha alpina R. Br.

Wardle et al. (2001); Zhang et al. (2004)

AF307909

AY230012

 Carpha sp.

Australia: Wilson et al. 9456 (K)

EF178574

 

 Carpha glomerata (Thunb.) Nees.

S. Africa: Muasya 1176 (K)

AY725941

 

 Caustis dioica R. Br.

Australia: Chase 2225 (K)

Y12976

 

 Cladium jamaicensis Crantz

Brazil: Thomas et al. 10403 (NY)

Y12988

 

 Cladium sp.

Brazil: Mayo 259 (K)

Y12950

 

 Cladium mariscus (L.) R. Br.

Locality unknown: MJC 292 (K)

DQ058338

DQ058298

 Costularia arundinacea (Sol. ex Vahl) Kük.

Zhang et al. (2004)

-

AY230036

 Costularia fragilis (Däniker) Kük.

New Calendonia McKee NSW41617 (K)

EU828589

 

 Costularia nervosa Raynal

Zhang et al. (2004)

-

AY230032

 Costularia pubescens Raynal

Zhang et al. (2004)

-

AY230037

 Cyathochaeta driandra (R. Br.) Nees

Zhang et al. (2004)

-

AY230042

 Cyathocoma bachmannii (Kuk.) C. Archer

S. Africa: Browning 835 (GENT)

EF200590

EF178604

 Cyathocoma hexandra (Nees) J. Browning

S. Africa: Verboom 648, BOL)

DQ058344

DQ058304

 Epischoenus quadrangularis (Boeck.) C. B. Clarke

S. Africa: Verboom 636 (BOL)

DQ058349

DQ058311

 Evandra aristata R. Br.

Australia: Wilson et al. 8974 (NSW)

AY725944

 

 Gahnia baniensis Benl.

Malaysia: Simpson 2737 (K)

DQ058342

DQ058302

 Gahnia deusta (R. Br.) Benth.

Australia: Alcock 11198 (WS)

U49231

 

 Gymnoschoenus sphaerocephalus (R. Br.) Hook. f.

Australia: Wilson et al. 9463 (K); Zhang et al. (2004)

AY725945

AY230033

 Lepidosperma tortuosum F. Muell.

Australia: Coveny et al. 17470 (K); Roalson et al. (2001)

AY725950

AF285074

 Machaerina mariscoides (Gaudich.) Kern

Tahiti: Sachet 2636 (GENT)

EF178575

 

 Machaerina sp.

New Guinea: Johns 9195 (K)

DQ058340

DQ058300

 Mesomelaena pseudostygia (Kük.) K. L. Wilson

Australia: Chase 2226 (K)

Y12959

DQ058301

 Mesomelaena tetragona (R. Br.) Benth.

Australia: Chase 2227 (K)

Y12949

 

 Morelotia gahniiformis Gaudich.

Hawaii: Herbst 1167 (GENT)

EF178576

 

 Neesenbeckia punctoria (Vahl) Levyns

S. Africa: Muasya 1214 (K)

AY725952

DQ058306

 Oreobolus kukenthalii Steenis

Malaysia: Simpson 2659 (K)

Y12972

EF178536

 Oreobolus obtusangulus Gaudich.

Wardle et al. (2001)

AF307926

 

 Oreobolus oligocephalus W. M. Curtis

Zhang et al., (2004)

-

AY230031

 Oreobolus pectinatus Hook. f.

Wardle et al. (2001)

AF307927

 

 Ptilothrix deusta (R. Br.) K. L. Wilson

Zhang et al. (2004)

-

AY230041

 Schoenus nigricans L.

Saudi Arabia: Edmondson 3382 (K)

Y12983

AJ295814

 Tetraria bolusii C. B. Clarke

S. Africa: Verboom 606 (BOL)

-

DQ058315

 Tetraria capillaris (F. Muell.) J. M. Black

Australia: Wilson et al. 9464 (K)

EF178577

 

 Tetraria compacta Levyns

S. Africa: Verboom 614 (BOL)

DQ058351

DQ058313

 Tetraria compar (L.) Lestib.

S. Africa: Verboom 549, (BOL)

DQ058350

DQ058312

 Tetraria crassa Levyns

S. Africa: Verboom 507 (BOL)

DQ058352

DQ058314

 Tetraria crinifolia (Nees) C. B. Clarke

S. Africa: Verboom 638 (BOL)

DQ058348

DQ058309

 Tetraria microstachys (Vahl) Pfeiffer

S. Africa: Verboom 640 (BOL)

DQ058347

DQ058307

 Tetraria thermalis (L.) C. B. Clarke

S. Africa: Verboom 643 (BOL)

-

DQ058308

 Trianoptiles solitaria (C. B. Clarke) Levyns

Zhang et al. (2004)

-

AY230028

 Tricostularia pauciflora (R. Br.) Benth.

Australia: Coveny et al. 17484 (K);Zhang et al. (2004)

AY725954

AY230038

Scirpeae Kunth ex Dumort.

   

 Amphiscirpus nevadensis (S. Watson) Oteng-Yeboa

Argentina: Charpin et al. 20575 (GENT)

DQ317926

DQ317925

 Eriophorum angustifolium Honckney

Simpson et al. (2003)

 

AY344177

 Eriophorum vaginatum L.

Poland: Beyer et al. 2 (K)

Y12951

AJ295769

 Eriophorum viridicarinatum (Engl.) Fern.

USA: Boufford 23053 (WS)

U49230

 

 Oreobolopsis clementis (M. E. Jones) Dhooge & Goetgh.

Dhooge (2005)

AJ811011

Dhooge (2005)

 Oreobolopsis inversa Dhooge & Goetgh.

Ecuador: Laegaard 21492 (GENT)

AJ811009

DQ317923

 Oreobolopsis tepalifera T. Koyama & Guagl.

Dhooge et al. (2003)

AJ575932

AJ576035

 Phylloscirpus acaulis (Phil.) Goetgh. & D. A. Simpson

Dhooge et al. 2003

AJ575926

AJ576029

 Phylloscirpus boliviensis (Barros) Dhooge & Goetgh.

Ecuador: Laegaard 102805 (GENT)

AJ566081

AJ566082

 Phylloscirpus deserticola (Phil.) Dhooge & Goetgh.

Ecuador: Laegaard et al. 21478 (GENT)

AJ704785

AJ704786

 Scirpus ancistrochaetus Schuyler

USA: Naczi 7544 (DOV)

EF178578

 

 Scirpus atrocinctus Fernald

USA: Naczi 10456 (DOV)

EF178579

 

 Scirpus cyperinus (L.) Kunth

USA: Naczi (DOV)

EF178580

 

 Scirpus expansus Fernald

USA: Naczi 10050 (DOV)

EF178581

 

 Scirpus flaccidifolius (Fernald) Schuyler

USA: Naczi 9774 (DOV)

EF178582

 

 Scirpus georgianus Harper

USA: Naczi 10458 (DOV)

EF178583

 

 Scirpus hattorianus Makino

USA: Naczi 10369 (DOV)

EF178584

 

 Scirpus pendulus Muhl.

USA: Naczi 10394 (DOV)

EF178585

 

 Scirpus polystachyus F. Muell.

Australia: Pullen 4091 (K)

Y12974

AJ295813

 Scirpus radicans Schkuhr

Czechia: Goetghebeur 9882 (GENT)

AJ811012

Dhooge (2005)

 Scirpus sylvaticus L.

HBUG/86–0541 (GENT)

EF178586

 

 Scirpus ternatanus Reinw. ex Miq.

Hong Kong: Shaw 917 (K)

EF178587

 

 Trichophorum alpinum (L.) Pers.

CANADA: Waterway 2002.95 (GENT)

AJ810999

DQ317924

 Trichophorum caespitosum (L.) Hartm.

British Isles: Nelmes 954 (K)

Y12969

Dhooge (2005)

 Trichophorum clintonii Gray

Canada: Baldwin 4856 (K)

Y12982

Dhooge (2005)

 Trichophorum planifolium (Spreng.) Palla

USA: Dhooge 24 (GENT)

AJ811001

Dhooge (2005)

 Trichophorum pumilum (Vahl) Schinz & Thellung

Uncertain locality: Morse & Jordon 2272 (GENT)

AJ811000

Dhooge (2005)

 Trichophorum rigidum (Steud.) Goetgh., Muasya & D. A. Simpson subsp. rigidum

Argentina: Renvoize et al. 5021 (K)

AJ297509

AJ295808

 Trichophorum rigidum subsp. ecuadoriensis Dhooge & Goetgh.

Ecuador: Laegaard et al. 21574 (GENT)

AJ811008

Dhooge (2005)

 Trichophorum subcapitatum (Thwaites & Hook.) D. A. Simpson

Papua New Guinea: Goetghebeur et al. 6581 (GENT)

AJ811006

Dhooge (2005)

 Zameioscirpus atacamensis (Phil.) Dhooge & Goetgh.

Bolivia: Ruthsatz & Budde 10328 (Trier)

AJ575929

AJ576032

 Zameioscirpus gaimardioides (E. Desv.) Dhooge & Goetgh.

Argentina: Ruthsatz 9212 (gent); Dhooge et al. (2003)

AJ575938

AJ576031

 Zameioscirpus muticus Dhooge & Goetgh.

Dhooge et al. (2003)

AJ575927

AJ576030

Sclerieae Kunth ex Fenzl

   

 Scleria distans Poir.

Kenya: Muasya 1023 (EA, K)

Y12968

DQ058299

 Scleria foliosa A. Rich.

Tanzania: Muasya 939 (EA, K)

Y12986

 

 Scleria terrestris (L.) Fassett

Malaysia: Simpson 2658 (K)

Y12947

 

Trilepideae Goetgh.

   

 Coleochloa abyssinica (A. Rich.) Gilly

Ethiopia: Vollesen 80/2 (K)

Y12975

 

 Microdracoides squamosus Hua

Bonn Acc. 150

AY725951

 

 Trilepis lhotzkiana Nees

Bonn Acc. s.n.

AY725955

 

Mapanioideae C. B. Clarke

Chrysitricheae Lestib. ex Fenzl

   

 Capitularia foliata Uitt.

Indonesia: Johns 8725 (K)

EF178588

 

 Capitularina involucrata (J. V. Suringar) Kern

Simpson et al. (2003)

 

AY344168

 Chorizandra cymbaria R. Br.

Bremer (2002)

AJ419940

 

 Chorizandra enodis Nees

Bremer (2002)

AJ419939

 

 Chorizandra sphaerocephala R. Br.

Simpson et al. (2003)

 

AY344170

 Chrysitrix capensis L.

S. Africa: Muasya 1242 (K)

AJ419938

AY344171

 Exocarya sclerioides (F. Muell.) Benth.

Simpson et al. (2003)

 

AY344167

 Lepironia articulata (Retz.) Domin.

Malaysia: Simpson 1236 (K)

Y12957

AY344169

Hypolytreae Presl ex Fenzl

   

 Diplasia karatifolia Rich. ex Pers.

Simpson et al. (2003)

 

AY344166

 Hypolytrum bullatum C. B. Clarke

Brazil: Thomas et al. 10318 (NY)

Y12956

 

 Hypolytrum nemorum (Vahl) Spreng.

Malaysia: Simpson 1379 (K)

Y12958

AJ295816

 Hypolytrum testui Cherm.

Simpson et al. (2003)

 

AY344163

 Mapania cuspidata (Miq.) Uittien

Brunei: Marsh 4 (K)

Y12955

AJ295817

 Mapania lorea Uitt.

Simpson et al. (2003)

 

AY344161

 Mapania meditensis D. A. Simpson

Brunei: Simpson et al. 2515 (K)

Y12954

AY344160

 Mapania tenuiscapa C. B. Clarke

Simpson et al. (2003)

 

AY344162

 Scirpodendron bogneri S.S. Hooper

Malaysia: Simpson 2650 (K)

Y12946

AY344164

 Scirpodendron ghaeri (Gaertn.) Merrill

Simpson et al. (2003)

 

AY344165

Outgroups

   

 Juncus effusus L.

Simpson et al. (2003); Chase et al., 1993

L12681

AY344156

 Juncus gerardii Loisel.

Simpson et al. (2003); Drabbkova et al. (unpublished)

AY216613

AY344157

 Luzula multiflora (Retz.) Lej.

Bremer (2002); Simpson et al. (2003)

AJ419945

AY344158

 Luzula sylvatica (Huds.) Gaud.

Simpson et al. (2003)

AY216637

AY344159

 Prionium serratum Drège

S. Africa: Gettliffe Norris, s.n. (NBG)

U49223

AY344155

Heuristic analyses were carried out using PAUP* (Swofford, 2002). Searches were conducted under Fitch (1971) parsimony, TBR (tree-bissection-reconnection) branch swapping, and random taxon addition (5,000) with the MulTrees option in effect and retaining only ten trees per replicate. Internal support was estimated using 1000 bootstrap replicates (Felsenstein, 1985), with the following search parameters: simple taxon addition, TBR branch-swapping, and MulTrees option in effect with only ten trees held per step.

The aligned matrix has 3,573 characters comprising 1,428 from rbcL and 2145 from trnl-F (intron and intergenic spacer) region. Some portions of trnl-F could not be unambiguously aligned, and 865 characters were excluded from the analysis, leaving 2,708 characters, of which 913 are potentially parsimony informative.

Fifty equally parsimonious trees were recovered of length = 5,467 steps, consistency index (CI) = 0.45 and retention index (RI) = 0.79. The strict consensus tree (Figs. 1, 2 and 3) is presented and discussed below.
https://static-content.springer.com/image/art%3A10.1007%2Fs12229-008-9019-3/MediaObjects/12229_2008_9019_Fig1_HTML.gif
Fig. 1

Maximum parsimony strict consensus tree of Cyperaceae, showing the outgroup and Cyperaceae tribes Hypolytreae (Hy), Chrysitricheae (Ch), Trilepideae (Tr), Schoeneae (Sc), Sclerieae (Scl), Bisboeckelereae (Bi) and Cryptangieae. Goetghebeur’s (1998) classification and the proposed classification are marked by grey and black bars respectively. Bootstrap support values shown as weak (* = 50–74%), moderate (** = 75–89%) and strong (*** = 90–100%)

https://static-content.springer.com/image/art%3A10.1007%2Fs12229-008-9019-3/MediaObjects/12229_2008_9019_Fig2_HTML.gif
Fig. 2

Maximum parsimony strict consensus tree of Cyperaceae, showing the Cyperaceae tribes Schoeneae (Sc), Cariceae, Scirpeae (S), Dulicheae (Du), Eleocharideae (El), Fuireneae (Fu), Abildgaardieae (Ab), Arthrostylideae (Ar), and Cypereae (Cy). Goetghebeur’s (1998) classification and the proposed classification are marked by black grey and black respectively. Bootstrap support values shown as weak (* = 50–74%), moderate (** = 75–89%) and strong (*** = 90–100%)

https://static-content.springer.com/image/art%3A10.1007%2Fs12229-008-9019-3/MediaObjects/12229_2008_9019_Fig3_HTML.gif
Fig. 3

Maximum parsimony strict consensus tree of Cyperaceae, showing the Cyperaceae tribes Cypereae (Cy), Scirpeae (S) and Chrysitricheae (Ch). Goetghebeur’s (1998) classification and the proposed classification are marked by grey and black bars respectively. Bootstrap support values shown as weak (* = 50–74%), moderate (** = 75–89%) and strong (*** = 90–100%)

Subfamily Relationships

Cyperaceae are resolved as monophyletic and sister to Juncaceae, with Mapanioideae sister to all the other Cyperaceae (Fig. 1; tribes and subfamilies sensu Goetghebeur, 1998). Within the last clade, Coleochloa-Microdracoides (Trilepideae) form a clade sister to the rest of Cyperaceae. Trilepideae are not sister to Scleria-Diplacrum (Sclerieae) as the latter are embedded in the Schoeneae, and therefore the Sclerioideae are not monophyletic. Also Caricoideae are sister to Scirpeae and embedded within Cyperoideae (Fig. 2).

Similar studies in which Mapanioideae are resolved as sister to rest of Cyperaceae have been reported by Bruhl (1995) based on morphological studies and in previous family-level DNA studies (e.g. Muasya et al., 1998, 2000b; Simpson et al., 2007). Mapanioideae have a unique floral morphology compared with the rest of Cyperaceae, with floral units each comprising two to ten or more scales (the lower ones being keeled), two to ten stamens and a single gynoecium. The floral units have been variously interpreted as bisexual flowers in which the arrangement of the structures has been disturbed (Goetghebeur, 1998) or as reduced partial inflorescences termed spicoids (Simpson et al., 2003; Richards et al., 2006).

Recognition of Caricoideae and Sclerioideae as subfamilies separate from Cyperoideae (e.g. Goetghebeur, 1998), based on unique morphological characters is not supported by current analysis. Typical Cyperoideae are mostly diagnosed by having at least one (sometimes all) bisexual flower, whereas in Sclerioideae (and some unusual Cyperoideae) they are all unisexual and in Caricoideae they are all unisexual and enclosed by a utricle. This study and other analyses of DNA data support the recognition of two subfamilies in Cyperaceae, Mapanioideae and Cyperoideae, as proposed by Simpson et al. (2003, 2007).

Tribes of the Cyperaceae

A number of tribal groups recognised in the recent classification of Cyperaceae by Goetghebeur (1998) are supported by the current study. Within Mapanioideae, some Hypolytreae (Mapania, Hypolytrum and Scirpodendron) and Chrysitricheae (Lepironia, Chrysitrix and Chorizandra) form clades separate from a polytomy comprising other mapanioids (Fig. 1). Although the polytomy observed may be caused by insufficient data for some of the taxa, Capitularina and Exocarya (both of which traditionally have been placed in Hypolytreae) were resolved together in Chrysitricheae in a combined pollen and DNA data study (Simpson et al., 2003).

The inselberg taxa in Trilepideae (Coleochloa to Microdracoides; Fig. 1) form a strongly supported clade. This clade is sister to the rest of Cyperoideae and not to other tribes of Sclerioideae (sensu Goetghebeur 1998), namely Cryptangieae, Sclerieae and Bisboeckelereae. These other tribes are embedded among Schoeneae (Fig. 1). Notable is the position of Exochogyne, a genus unplaced in any tribe of Sclerioideae by Goetghebeur (1998) due to unclear morphological homologies, and which is resolved here among Cryptangieae.

Schoeneae are one of the most heterogeneous tribes in the family, having 29 genera of which Rhynchospora is among the largest; over 50% of the genera have fewer than 10 species (Goetghebeur, 1998). This analysis resolves four clades within Schoeneae: (1) Cladium, (2) Gymnoschoenus, (3) Caustis to Didymiandrum, and (4) Rhynchospora (Figs. 1 and 2). The moderately supported Rhynchospora clade has been previously classified in a separate tribe Rhynchosporeae (e.g. Goetghebeur, 1986; Bruhl, 1995) on the basis of, inter alia, distinct style base. Members of the former Sclerioideae (Cryptangieae, Bisboeckelereae and Sclerieae) are resolved among clade (3), an observation reported in previous studies (e.g. Simpson et al., 2007). Schoeneae have an essentially Gondwanan distribution, and several widely distributed genera (e.g. Costularia, Tetraria; Zhang et al., 2004, Verboom, 2006) are polyphyletic. Morelotia is resolved in a clade which includes Costularia, Tricostularia and reticulate-sheathed Tetraria (Tricostularia clade in Verboom, 2006), and not together with Ghania. A close relationship between Morelotia and Ghania has been suggested by several authors (e.g. Goetghebeur, 1986), while Bruhl (1995) argued against this relationship after recovering Morelotia distant from Ghania. The monotypic Schoenoides (Seberg, 1988) is embedded in Oreobolus here and in other studies (Mandriñán et al., 2004), further supporting the inclusion of Schoenoides in Oreobolus (e.g. Curtis & Morris, 1994; Govaerts et al., 2007). There have been limited phylogenetic studies in Schoeneae (e.g. Zhang et al., 2004; Verboom, 2006), which lack bootstrap support for the basal nodes, and more data are needed to resolve relationships among the taxa. Further studies of Schoeneae are in progress (Bruhl et al. and Verboom et al., unpublished data).

The moderately supported clade (Khaosokia to Dulichium) includes members of Cariceae, Scirpeae and Dulicheae (Fig. 2). Khaosokia is resolved sister to the rest of the members of this clade, a position suggested by Simpson et al. (2005) from observations of gross morphology and DNA studies. Scirpeae are not monophyletic, as Dulicheae are embedded between Scirpeae I and Scirpeae II. In Scirpeae I, the generic boundaries between Trichophorum and Oreobolopsis are unclear, and further attention is needed to resolve the polyphyly of Trichophorum. Phylogenetic studies involving Andean species of Scirpus have recently led to description of a new segregate genus, Zameioscirpus (e.g. Dhooge et al., 2003). Carex is polyphyletic and includes other genera of Cariceae, a similar pattern has been observed in previous studies (e.g. Yen & Olmstead, 2000; Starr et al., 2004)

Fuireneae are split into four clades (Fig. 2) in our analysis. Fuireneae I (Fuirena) is sister to Eleocharideae, Fuireneae II (Bolboschoenus) is sister to Abildgaardieae, whereas Fuireneae III (Schoenoplectus and Actinoschoenus) and Fuireneae IV (Schoenoplectiella group) form a polytomy with Cypereae. Relationships among these groups based on DNA data remain unstable (cf. Simpson et al., 2007). Schoenoplectus is paraphyletic with several tropical African perennial taxa (e.g. S. mucronatus) being resolved together with Schoenoplectiella. Schoenoplectiella, recently segregated to include annual amphicarpous taxa of Schoenoplectus (Lye, 2003), is resolved into a strongly supported clade that includes perennial tropical Schoenoplectus species sharing a lateral spikelet morphology. Further studies are in progress (Muasya et al., unpublished data) evaluating relationships in the group.

Abildgaardieae are resolved to include Arthrostylis aphylla, Trachystylis strandbrokensis and Actinoschoenus repens (Fig. 2), taxa which have been previously placed in Schoeneae (Goetghebeur, 1998). Arthrostylis and Actinoschoenus have been shown to be closer to Abildgaardieae based on plastic and nuclear ribosomal (ITS) data (Ghamkhar et al., 2007). Both Arthrostylis and Trachystylis are monotypic Australian taxa with bisexual flowers that lack perianth segments, but share gross morphological similarity with Schoeneae (e.g. one- to few-flowered spikelet and wide glume wings enclosing the next flower). On the other hand, Actinoschoenus repens is a Zambian endemic, with morphological similarity to both Abildgaardieae and Schoeneae. Although these three taxa had been placed in Schoeneae even with decisive anatomical and embryological data lacking, the DNA data resolve them in Abildgaardieae, and similar results were obtained independently by Ghamkhar et al. (2007). We therefore propose their formal inclusion in this tribe.

Cypereae form a strongly supported clade (Fig. 3) that has received intensive DNA phylogenetic study, both at generic (e.g. Muasya et al., 2001, 2002) and tribal levels (Muasya et al., 2008). Cypereae are characterised by the presence of Cyperus-type embryo and here include Hellmuthia, a genus previously considered to belong in Chrysitricheae (e.g. Haines & Lye, 1976; Goetghebeur, 1998; cf. Vrijdaghs et al., 2006, 2008). Scirpus falsus and S. ficinioides, taxa from the Drakensberg Mountians in South Africa and previously placed in Scirpeae, are resolved here among Cypereae in a clade including Ficinia, Isolepis, Hellmuthia and Scirpoides. More studies are in progress to describe a new genus including these taxa (authors, unpublished data).

Revised Suprageneric Classification of Cyperaceae

Based on the available data, we support the revised classification of Cyperaceae into two subfamilies, Mapanioideae and Cyperoideae (Figs. 1, 2 and 3). We also broadly accept the tribal circumscriptions of Goetghebeur (1998) but with modification to tribes Cypereae (to include Hellmuthia and the perianth-bearing Drakensberg Scirpus, S. falsus and S. ficinioides); Abildgaardieae (to include Arthrostylis, Trachystylis and Actinoschoenus); Schoeneae (recognising Rhynchosporeae, Rhynchospora and Pleurostachys); and Cryptangieae (to include Didymiandrum and Exochogyne). We refrain from recognising Cladieae (Cladium) pending more studies.

Future Research

Choice of marker and uneven sampling limit the scope for analysing different data sets in combination. The current study and a number of other ongoing studies have focused on more slowly evolving plastid regions, which have less resolution but can be aligned across the family. Among research groups in different institutes, there is need to study the same DNA regions (e.g. rbcL, trnl-F, rps16) for similar taxa to enable different data sets to be aligned in combination.

The intensity of sampling varies among tribes. Although Chrysitricheae, Cypereae, Hypolytreae, Scirpeae and Cariceae are among the better studied tribes, more effort is needed to elucidate phylogenetic relationships within Cryptangineae, Bisboeckelerieae, Fuireneae, Schoeneae, and Sclerieae.

Acknowledgements

A number of the contributors acknowledge funding from various sources. AMM acknowledges funding from the Belgian Fund for Scientific Research-Flanders (FWO-Vlaanderen, G.0104.01N); K.U.Leuven (grant F/02/052); University of Cape Town (Smuts Fellowship); and the Norwegian Council of Universities’ Committee for Development Research and Education (NUFU project 53/03). GAV acknowledges funding from the National Research Council, South Africa.

Open Access

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Copyright information

© The Author(s) 2008

Authors and Affiliations

  • A. Muthama Muasya
    • 1
    • 6
  • David A. Simpson
    • 2
  • G. Anthony Verboom
    • 1
  • Paul Goetghebeur
    • 3
  • Robert F. C. Naczi
    • 4
  • Mark W. Chase
    • 2
  • Erik Smets
    • 6
    • 5
  1. 1.Botany DepartmentUniversity of Cape TownCape TownSouth Africa
  2. 2.Royal Botanic GardensKewUK
  3. 3.Department of BiologyGhent UniversityGhentBelgium
  4. 4.Department of Agriculture & Natural ResourcesDelaware State UniversityDoverUSA
  5. 5.National Herbarium of the NetherlandsLeidenThe Netherlands
  6. 6.Laboratory of Plant SystematicsLeuvenBelgium