植物研究雑誌 J. J. Jpn. Bo t. 76: 76: 339-343 (200 1)

Delineation Delineation of Schoenoplectus sect. Malacogeton () ， New Combination ，and Distinctions of Species

a b S. S. Galen SMITH and Eisuke HA YASAKA

aDepartment aDepartment of Biology ，University of Wisconsin-Whitewater ， Whitewater ，Wisconsin ， 53190 U.S. A.; bBotanical bBotanical Garden ，Graduate School of Science ，Tohoku University ，Sendai ， 980-0862 JAPAN

(Received (Received on 乱1ay 14 ， 2001)

The new combination ，Schoenoplectus sec t. Malacogeton (Ohwi) S. G. Smith & Hayasaka ， is made and a description of the section is provided. Schoenoplectus nipponicus ，Sc h. etuberculatus ，Sch. torreyi and Sch. subterminalis 訂 e included in sec t. Malacogeton ， and a key to these is given. We recognize the sections Schoenoplectus ， Actaeogeton ， Malacogeton and Supini in the genus Schoenoplectus ， and a key to the sec- tions tions and a list of North American and East Asian species included in each section are provided. provided.

Key words: Cyperaceae ， new combination ， Schoenoplectus sec t. Malacogeton ， taxonomy

The polymorphic and polyphyletic 2000 ， Koyama et al. 2000 ， Smith and L. L. s. la t. in recent ye 紅 s has been subdivided Yatskievych 1996 ，Wilson 1981). Of these into into about 17 genera (Bruhl 1995 ， segregate genera Schoenoplectus is comp 紅 a- Goetghebeur 1998 ， Wilson 1981 ， 1989). tively large ， with species distributed world- Scirpus Scirpus as stric t1 y defined includes about 30 wide ， the number of which is v紅 iously species species occurring mainly in the temperate re- estimated at 50 spp. (Goetghebeur 1998) ，60 gions gions of the Northem Hemisphere ， with S. spp. (Wilson 1981) ，80 spp. (Hooper 1985) ， sylvaticus sylvaticus L. as the type species (Wilson or over 130 spp. (Koyama et al. 2000). For 1989). 1989). The rest of Scirpus s. la t. has been North America and East Asia ，34 species are placed placed in Actinoscirpus (Ohwi) R. W. Haines here recognized (Appendix 11). Following & Lye ， Amphiscirpus Oteng ・.Yeboah ， Goetghebeur and Simpson (1 991) ，we here Bolboschoenus (Asch.) Palla ， Blysmopsis define Schoenoplectus as excluding Oteng- Yeboah ，Blysmus Schul t.， Eleogiton Bolboschoenus and the monotypic Link ， Ficinia Schrad. ， Isolepis R.Br. ， Actinoscirpus ，which are sometimes included O 砂 ca ηum Nees ，Phylloscirpus C.B.Clarke ， in it (Lye 1995 ， Strong 1994). Pseudoschoenus (C.B.Clarke) Oteng- Schoenoplectus as currently delimited is Yeboah ， Schoenoplectus (Rchb.) Palla ， commonly characterized by its pseudolateral Scirpoides Scirpoides Seg. ， Sumatroscirpus Oteng- ，i. e. ， the proximal usu- Yeboah ，Trichophorum Pers. ，and Websteria ally erect and resembling the culm (Wilson S.H.Wright S.H.Wright by recent cyperologists (Bruhl 1981). Close examination shows that this is 1995 ， Goetghebeur and Simpson 1991 ， a superficial character ，however ， because the Goetghebeur 1998 ，Hayasaka and Ohashi proximal involucI 叫 of many species

-339- 340 植物研究雑誌第76 巻第6号 平成13 年12 月 now included in Schoenoplectus usually characters such as long leaf blades with un- closely closely resemble the foliage leaf blades and usual architecture ， weak often 訂 e commonly divergen t. Thus other charac- terminated by tubers ， and often aquatic habi- ters ters are now used ，especially embryo form tat and flaccid habi t. Close examination (van (van der Veken 1965 ， Wilson 1981) ，stolon shows that these four species all belong to presence ， tuber presence and form ，ligule Scirpus sec t.乱 1alacogeton Ohwi [= presence ，culm branching ，leaf position ， leaf Schoenoplectus subg. 孔1alacogeton (Ohwi) structure ，spikelet a町 angement ，floral scale Oteng-Yeboah]. The required new combina- indument ， and culm anatomy. tion is provided as follows.

Species Species relationships within Schoeno ・ plectus 紅 e not clear because of large mor- Schoenoplectus (Rchb.) Palla in Verh. K. phological phological variation in the characters of the K. Zoo l. -Bo t. Ges. Wien 38 (Sitzungsber.): rhizomes ，leaves ，inflorescences ，achenes ， 49 (1888) ， nom. cons. floral floral bristles and other structures that have Sec t. Malacogeton (Ohwi) S.G.Smith & been been used to define the infrageneric taxa. To Hayasaka ， comb. nov. clarify clarify the species relationships within the Scirpus L. subgen. Schoenoplectus Rchb. genus ，a modern infrageneric system should sec t. Malacogeton Ohwi in Mem. Coll. Sci. be be established. This was attempted by Kyoto Imp. Univ. se r. B ， 18: 97 (1944). Oteng-Yeboah Oteng-Yeboah (1974) and Raynal (1976b) ， Scirpus sec t. Bolboschoenus Asch. ser. but but neither of their treatments 征 e satisfac- Malacogeton (Ohwi) T. Koyama in J. Fac. tory tory (Wilson 1981). In his brief paper ， Sci. Univ. Tokyo ，sec t. 3 ，7: 288 (1 958).

Oteng-Yeboah Oteng-Yeboah (1 974) recognized and pro 四 Schoenoplectus subgen. Malacogeton vided vided a key to the three subgenera (Ohwi) Oteng-Yeboah in Notes Roy. Bo t. Schoenoplectus ， Actaeogeton and Malacoge- Gard. Edinb. 33: 315 (1 974). ton ， but he neither gave descriptions for the Perennials ， erect or flaccid ， 40-200 cm subgenera subgenera nor the included species except high. Rhizomes long ，weak ， very soft ， often for for the type species. Raynal (1 976a ，b ， 1977) terminated by fleshy tubers to ca. 3 mm recognized recognized the four sections Schoenoplectus ， thic k. Culms trigonous or terete ， ca. 0.5-5 Actaeogeton ，Supini ， and Pterolepis; with mm thic k. Leaves basal ， ca. 3 to more than emphasis emphasis on sec t. Supini ， in which he recog- 20; sheaths often free from culm and resem- nized nized 21 species ， mainly from Africa. His bling blades; sheath fronts hyaline ，splitting detailed detailed study of Sch. sec t. Supini should be early ，usually pinnate- fibrillose; blades 2 to extended extended to the rest of the species to provide ca. 20 per culm ，some species forming emer- a more complete classification for Schoeno- gent ，erect blades an d/ or submerged ，flaccid

plectus. plectus. The present paper ， which empha- blades ，cross-section mostly trigonous or lat 同 sizes sizes East Asian and North American erally flattened ， apices often blunt and ec- species ，contributes to the establishment of a centric; distal bl 争de longer than sheath ， ca. Ill odern in 仕ageneric system for the genus. It 0.2-10 mm wide. Inflorescences of one

also also provides the name Schoenoplectus sec t. spikelet or capitate or 1x ーto 3x ー branched; 乱1alacogeton and other information needed proximal bract erect ，structure like foliage for for the senior author' s 位eatment of the genus leaf blades ，ca. 1-32 cm long. Spikelets 1 to in in an upcoming volume of the Flora of N orth 20 per ， 5-25 x 3-6 mm. Floral America America (Flora of North America Editorial scales narrowly oblong-ovate ， 4-7 mm long ， Committee Committee 2001). smooth or awn sparsely spinulose ，some- In In Schoenoplectus three species in eastern times sp 訂 sely ciliolate distally ，flanks each N orth America and one in East Asia share usually with 2 to ca. 10 prominent veins (at December 2001 Journa1 of Japanese Botany Vo 1. 76 No. 6 341 least least in proximal part of spikelet) ， apices ing achene; eastern North American subacute ，entire or minutely notched ，awn coastal plains …・・ -

(extension (extension of midrib) ca. 0.1-0.5 mm. …...・ H ・.Schoenoplectus etuberculatus

Perianth Perianth bristles stout ， from ca. 1/2 of 同 to 3. Leaf blades ca. 1-2 mm wide; floral twice twice achene length ，retrorsely to antrorsely scales awned ， the apical midrib exten- spinulose. spinulose. Anthers ca. 2-3.5 mm long. Styles sions 0.2 -0 .5 mm; inflorescence of 1 to 4 3-fid 3-fid or 2-fid. Achenes yellow- to dark spikelets; not forming submerged mead- brown when ripe ， ovoid to obovoid ，promi- ows; widespread in eastern North

nently nently beaked ， compressed-trigonous or America ...・ H ・...・ H ・.Schoenoplectus torreyi biconvex ，2 -4 .5 mm ， smooth. Flowers ab- 3. Leaf blades 1 mm or less wide; floral sent sent from basal sheaths. Fresh-water lakes ， scales mucronate ， the apical midrib ex- ponds ，streams ，ditches ， often deeply emer- tensions to 0.1 mm; inflorescence of one gent gent or submerged aquatic ， in deep water erect spikelet; forming submerged mead- flaccid flaccid and sometimes entirely vegetative. ows of vegetative in deep or flow- Chromosome numbers reported: 2n = 42 ， ing water; widespread in N orth America ， 70 ，74 ， 76. mostly eastern... …・ Type species: Schoenoplectus n伊'/)onicus …. .Schoenoplectus subterminalis (Makino) (Makino) Sojak. The type species is Sch. nipponicus ， not Koyama (1 958 ， under Scirpus) confused Sch. Sch. etuberculatus as stated by Oteng- the species of Sch. sec t. Malacogeton with Yeboah (1 974) ， because Ohwi (1 944) ， in his those of Bolboschoenus ， which is now key key to species of Scirpus subg. treated as a distinct genus even when Scirpus Schoenoplectus ， established Scirpus sec t. is treated in a broader sense including Malacogeton ， and included only Scirpus Schoenoplectus (Kozhevnikov 1988). Oteng- nipponicus. nipponicus. Koyama (1 958) reduced Scirpus Yeboah (1 974) reg 紅 ded Sc h. sec t. nipponicus nipponicus to S. etuberculatus subsp. Malacogeton as intermediate between n伊ponicus ， and Oteng-Yeboah (1 974) ap- Schoenoplectus and Bolboschoenus but parently parently adopted Koyama's treatment of S. closer to the former in having a 'net-like nipponicus nipponicus and gave Sch. etuberculatus as ground tissue' and other characters. the the type species of Sch. subg. Malacogeton. Schoenoplectus sec t. Malacogeton is here We think the diagnostic characters of Sch. considered to be distinguishable from the sec t. Malacogeton 紅 'e not sufficient to 回 at other sections as indicated in the key to the it it as a subgenus ， but still great enough to rec- sections below (Appendix 1). A close rela- ognize ognize it as a distinct section. tionship between Sc h. sec t. Malacogeton and Sc h. sec t. Schoenoplectus was suggested by Key to species of sect. Malacogeton van der Veken (1965) based on embryo mor- 1. 1. Inflorescences branched ， of 3 to 25 phology.

spikelets …...・ H ・.....・ H ・.....・ H ・.....・ H ・.....・ H ・-… 2 The leaf architecture of sec t. Malacogeton 1. 1. Inflorescences unbranched ， of 1 to 5 appear to be unique in Schoenoplectus. Both

spikelets …...・ H ・.....・ H ・..…...・ H ・..…...・ H ・..… ..3 Sch. etubercul α tus and Sch. subterminalis 2. 2. Styles bifid; achenes biconvex ，ca. 2 mm may form submerged ，flaccid leaf blades long; long; perianth bristles two times longer an d/ or emergent ， erect blades as described than than achene; East Asia... and illustrated by Schuyler (1 972). In the … Schoenoplectus nipponicus emergent blades of Sc h. n伊'/)onicus ， Sch. 2. 2. Styles trifid; achenes trigonous ，2.5 -4 .5 etuberculatus ， and Sch. torreyi ， the cross- mm long; perianth bris t1 es about equal- sections just distal to the ligules are thickly 342 342 植物研究雑誌第76 巻第6号 平成13 年12 月

V -shaped to trigonous ， then in the central re- ed. 5: 191-317. National Taiwan University ， gions gions become acutely trigonous or laterally Taipei. flattened flattened with one edge channeled ， then to- Kozhevnikov A. E. 1988. Cyperaceae. In: Charkevicz S. S. S. (ed よ Plantae Vasculares Orientis Extremi ward the apex become asymmetrically Sovietici 3: 175 -4 03. Nauka ，Leningrad. flattened-trigonous. flattened-trigonous. In the wider leaf blades Lye K. A. 1995. Cyperaceae. In: Thulin M. (ed よFl ora of of Sc h. etuberculatus and Sc h. torreyi ， the of Somalia 4: 98-147. Royal Botanic Gardens ， apices apices are blunt and markedly asymme 住ic ， Kew. with with the actual apex tumed to one side. Oteng-Yeboah A. A. 1974. Taxonomic studies in Cyp- eraceae-Cyperoideae. eraceae-Cyperoideae. Notes Roy. Bo t. Gard. Schoenoplectus sec t. MaIacogeton is an Edinb. Edinb. 33: 311-316. example example of flowering plants with a disjunct Raynal J. 1976a. Notes Cyperologiques: 25. Le genre distribution distribution pattern between East Asia and Schoenoplectus 1. Sur quelques especes Sud- North North America ，p ぽ ticularly referred to as Africaines. Adansonia ， se r. 2， 15: 537-542. East East Asian-eastern North American distribu- 一一一. 1976b. Notes Cyperologiques: 26. Le genre Schoenoplectus Schoenoplectus 11. L'amphic 征 pie et la sec t. Supini. tion tion type ， such as in Panax ，Symplocarpus ， Adansonia ， se r. 2， 16: 119 ー155. Zizania ， and Hamamelis (Wen 1999). 一一一. 1977. Addendum to notes Cyperologiques 26. Adansonia ， se r. 2， 16: 530. We thank the curators of Tohoku Schuyler A. E. 1972. Morphological and anatomical University University Herbarium (TUS) and many differences in leaf blades of three North American N orth American Herbaria for the loan of aquatic bulrushes (Cyperaceae: Scirpus). Bartonia 41: 41: 57-60. specimens ， and Mark Strong for helping the Smith Smith S. G. and Yatskievych.G. 1996. Notes on the senior senior author prep 訂 'e an early version of an genus Scirpus sensu lato in Missouri. Rhodora 98: infrageneric infrageneric classification of Schoenoplectus. 168-179. Strong Strong M. T. 1994. Taxonomy of Scirpus ， References References Trichophorum ， and Schoenoplectus (Cyperaceae) in in Virginia. Bartonia 58: 29-68. Bruhl Bruhl J. 1995. Sedge genera of the world: relation- Tang T. and Wang F.-T. 196 1. Scirpus. In: Chien S.-S. ships ships and a new classification of the Cyperaceae. and and Chun W.-Y. (eds よFl ora Reipublicae Aus t. Sys t. Bot. 8: 125-305. Popularis Popularis Sinicae 11: 2-34. Science Press ，Beijing. Flora Flora of North America Editorial Committee (作 ed む吋.) s. van van der Veken P. 1965. Contribution a l' embryogra- 、 200 1. 日1J. F 凹ora ぱ0f North America north of Mexico. 4+ phie phie systematique des Cyperaceae-Cyperoideae. vols. ， Oxford Univ. Pr ess ，New York and Oxford. Bull. Bull. Jard. Bo t. Etat Bruxelles 35: 285-354. Goetghebeur Goetghebeur P. 1998. Cyperaceae. In: Kubitzki K. Wen J. 1999. Evolution of eastem Asian and eastem (ed よThe families and genera of vascular plants 4: North North American di 司unct distributions in flowering 141-190. 141-190. Springer ，Berlin. plants. plants. Ann. Rev. Eco l. Sys t. 30: 421 -4 55. 一一一. and Simpson D. A. 199 1. Critical notes on Wilson Wilson K. L. 198 1. A synopsis of the genus Scirpus Actinoscirpus ， Bolboschoenus ，Isolepis ，Phyllo- sens. sens. la t. (Cyperaceae) in Australia. Telopea 2: scirpus scirpus and Amphiscirpus (Cyperaceae). Kew Bul l. 153-172. 153-172. 46: 46: 169-178. 一一. (931) 1989. Proposal to conserve 468 Scirpus L. Hayasaka Hayasaka E. and Ohashi H. 2000. New combinations (Cyperaceae) with (Cyperaceae) S. sylvaticus L. as type. Taxon in in Japanese Schoenoplectus (Cyperaceae). J. Jpn. 38: 38: 316-320. Bo t. 75: 223-225. Hooper Hooper S. S. 1985. Cyperaceae. In: Townsend C. C. Appendix 1. Key to the Sections of Schoeno ・ and and Guest E. (eds よFl ora of Ir aq 8: 331 -4 06 ， plectus plectus Ministry Ministry of Agriculture & Agrarian Reform ， 1. 1. Achenes rugulose ，blackish when ripe; floral scale Republic Republic of Ir aq. apices apices entire; plants densely tufted ， rhizomes very Koyama T. 1958. Taxonomic study of the genus short ， or in Sch. lineolatus spreading by long rhi- Scirpus Scirpus L. J. Fac. Sci. Univ. Tokyo ，sec t. 3 ，7: 271- 366. 366. zomes... ・H ・.....・ H ・-…・・ H ・H ・-… H ・H ・-… H ・H ・-…....・ H ・...・ H ・-・ .2 1. 1. Achenes smooth ，yellow- to dark brown when ripe; 一一一， Kuoh C.-S. and Leong W.-C. 2000. Cyperaceae. floral floral scale apices clearly em 紅 ginate to bifid ， or In: In: Huang T. ーC. & al. (eds.) ， Flora of Taiwan ，2nd entire entire or nearly so in sec t. Malacogeton; plants December December 2001 Joumal of Japanese Botany Vo l. 76 No. 6 343

widely widely spreading by rneans of rhizornes ....・ H ・-…… 3 (Torr.) Sojak; Sc h. torreyi (Olney) Palla 2. 2. One (rarely 2) node and leaf usually present on It is possible that Sch. ehrenbergii (Boc k.) S吋ak culrn culrn above basal leaf sheaths; plants often with (see fig. 7 in Tang and Wang 1961) of China and S. E. flowers flowers in bas}l leaf sheaths; perianth bristles ab- Russia rnight be included in sec t. Malacogeton ， but we sent sent frorn spikelet flowers ，sornetirnes present in exclude it here pending further inforrnation.

basal basal flowers. …...・ H ・.....・ H ・-…....・ H ・.....・ H ・.sect. Supini 2. 2. All nodes crowded at base of culrn; plants never Schoenoplectus sec t. Actaeogeton (Rchb.) J.Raynal forrning forrning flowers in basalleaf sheaths; perianth bris- Sch. かscorubens (T.Koyarna) T.Koyarna; Sch.

tles tles present or absen t....・ H ・H ・H ・..… sec t. Actaeogeton hondoensis (Ohwi) Sojak; Sch. hotarui (Ohwi) Holub; 3. 3. Fl oral scale flanks each with 2 to ca. 10 prorninent Sch. juncoides (Roxb.) Palla; Sch. komarovii (Roshev.) veins ， at least in proxirnal p紅 t of spikelet ，apices Sojak; Sch. lineolatus (Franch. & Sav.) T.Koyarna; entire entire or obscurely ernarginate; rhizornes weak ， Sch. mucronatus (L.) Palla [type species]; Sc h. soft soft when rnature ， tubers often terrninating rhi- ohwianus (T.Koyarna) Holub; Sch. orthorhizomatus zornes; zornes; often subrnerged aquatic; North Arnerica (Arai & Miyarn.) Hayasaka & H.Ohashi; Sc h.

and and East Asia... ・H ・H ・H ・..…...・ H ・..… .sec t. Malacogeton purshianus (Fem.) M.T.Strong; Sch. smithii (A. Gray) 3. 3. Floral scale flanks without veins (except often on S吋ak; Sch. subbisetosus (T.Koyarna) Sojak; Sch. basal basal scales) ， apices clearly ernarginate to deeply triangulatus (Roxb.) Sojak; Sch. wallichii (Nees) bifid; bifid; rhizornes strong ， hard when rnature ，tubers T.Koyarna absent; absent; ernergent aquatic or on wet soils (Sch. lacustris lacustris sornetirnes subrnerged aquatic); world- Schoenoplectus sec t. Supini (Cherrn.) J.Raynal

wide.. ・H ・.....・ H ・...・ H ・....・ H ・...・ H ・... sec t. Schoenoplectus Sch. articulatus (L.) Palla; Sch. erectus (Poir.) Palla ex J.Raynal; J.Raynal; Sch. hallii (A. Gray) S.G.Srnith; Sc h. Appendix 11. List of Sections and Included sα ximontanus (Fem.) J.Raynal; Sc h. supinus (L.) Palla Species Species from North America and East Asia [type species] Schoenoplectus Schoenoplectus sec t. Schoenoplectus Sch. Sch. acutus (Muh l. ex Bigelow) A. Love & D.Love; The infrageneric classification of Schoenoplectus Sch. Sch. americanus (Pers.) Volkart; Sch. californicus given herein is based rnainly on East Asian and North (C. A. Mey) Sojak; Sch. deltarum (Schuyler) Sojak; Sch. Arnerican species. A rnore cornplete infrageneric sys- heterochaetus heterochaetus (Chase) Sojak; Sch. lacustris (L.) Palla tern based on world-wide species is needed. It is possi- [type [type species]; Sc h. litoralis (Schrad.) Palla; Sch. ble that rnore than four sections rnight be recognized pungens pungens (Vahl) Palla; Sch. tabemaemontani (C. C. within the genus ， because sorne African species ，e. g. ， Grne l.) Palla; Sc h. triqueter (L.) Palla Sch. muriculatus (Kuk.) J.Browning and Sch. paludicola paludicola (Kunth) Palla ex J.Raynal cannot definitely Schoenoplectus Schoenoplectus sec t. Malacogeton (Ohwi) S.G.Srnith be assigned to either of the four sections. In 仕asectional ， & Hayasaka taxa rnight also be recognized after a rnore detailed Sc h. etuberculatus (Steud.) Sojak; Sc h. nipponicus study of species ，especially in sec t. Schoenoplectus. (M 北ino) S吋ak [type species]; Sch. subterminalis

スミス S. G 人早坂英介b .フトイ属シズイ節(カ ヤツリグサ科)の学名の新組み合わせ，節の定義 と種の区別 点を明らかにした.また フトイ属に 4 節 sec t. フトイ属シズイ節の学名の新組み合わせ Schoenoplectus フトイ節; sec t. Malacogeton シズイ Schoenoplectus Schoenoplectus (Rchb.) Palla sec t. Malacogeton 節， sec t. Actaeogeton (Rchb.) J.Raynal カンガレイ (Ohwi) (Ohwi) S.G.Srnith & Hayasaka を提唱し，節の形態 節， sec t. Supini (Cherrn.) 1. Raynal ホソガタホタル 的な特徴を記載した.シズイ節には北米に 3 種 イ節を認めてこれらの節への検索表を示し，それ Sc h. etuberculatus (Steud.) S吋ak ， Sch. subterminalis ぞれの節に含まれる北米と東アジアの種を一覧し (Torr.) (Torr.) Sojak ， Sch. torreyi (Olney) Palla ，および東ア た. ジアに 1 種 Sc h. nipponicus (Makino) S吋ak シズイ (a ウイスコンシン大学生物学部，

がある.これらの種への検索表を示し，種の区別 b東北大学大学院理学研究科付属植物園)