Juncus × Diffusus

''Juncus'' is a genus of monocotyledonous flowering plants, commonly known as rushes. It is the largest genus in the family Juncaceae, containing around 300 species.

Description

Rushes of the genus ''Juncus'' are herbaceous plants that superficially resemble grasses or sedges. They have historically received little attention from botanists; in his 1819 monograph, James Ebenezer Bicheno described the genus as "obscure and uninviting".

The form of the flower differentiates rushes from grasses or sedges. The flowers of ''Juncus'' comprise five whorls of floral parts: three sepals, three petals (or, taken together, six tepals), two to six stamens (in two whorls) and a stigma with three lobes. The stems are round in cross-section, unlike those of sedges, which are typically somewhat triangular in cross-section.

In ''Juncus'' section ''Juncotypus'' (formerly called ''Juncus'' subg. ''Genuini''), which contains some of the most widespread and familiar species, the leaves are reduced to sheaths around the base of the stem and the bract subtending the inflorescence closely resembles a continuation of the stem, giving the appearance that the inflorescence is lateral.

Distribution and ecology

''Juncus'' has a cosmopolitan distribution, with species found throughout the world, with the exception of Antarctica. They typically grow in cold or wet habitats, and in the tropics, are most common in montane environments.

Fossil record

Several fossil fruits of a ''Juncus'' species have been described from middle Miocene strata of the Fasterholt area near Silkeborg, Denmark.Angiosperm Fruits and Seeds from the Middle Miocene of Jutland (Denmark) by Else Marie Friis, The Royal Danish Academy of Sciences and Letters 24:3, 1985

Classification

The genus ''Juncus'' was first named by Carl Linnaeus in his 1753 '. The type species of the genus was designated by Frederick Vernon Coville, who in 1913 chose the first species in Linnaeus' account, '' Juncus acutus''. ''Juncus'' can be divided into two major groups, one group with cymose inflorescences that include bracteoles, and one with racemose inflorescences with no bracteoles.

The genus is divided into the following subgenera and sections:
* ''Juncus'' subg. ''Juncus''
** sect. ''Juncus''
** sect. ''Graminei'' (Engelm.) Engelm.
** sect. ''Caespitosi'' Cout.
** sect. ''Stygiopsis'' Kuntze
** sect. ''Ozophyllum'' Dumort.
** sect. ''Iridifolii'' Snogerup & Kirschner
* ''Juncus'' subg. ''Poiophylli'' Buchenau
** sect. '' Tenageia'' Dumort.
** sect. ''Steirochloa'' Griseb.
** sect. ''Juncotypus'' Dumort.
** sect. ''Forskalina'' Kuntze

Species

''Plants of the World Online'' accepts the following species in the genus ''Juncus'':

*'' Juncus acuminatus'' Michx.
*'' Juncus acutiflorus'' Ehrh. ex Hoffm.
*'' Juncus acutus'' L.
*'' Juncus aemulans'' Liebm.
*'' Juncus alatus'' Franch. & Sav.
*'' Juncus alexandri'' L.A.S.Johnson
*'' Juncus allioides'' Franch.
*'' Juncus alpigenus'' K.Koch
*'' Juncus × alpiniformis'' Fernald
*'' Juncus alpinoarticulatus'' Chaix
*'' Juncus amabilis'' Edgar
*'' Juncus amplifolius'' A.Camus
*'' Juncus amuricus'' (Maxim.) V.I.Krecz. & Gontsch.
*'' Juncus anatolicus'' Snogerup
*'' Juncus anceps'' Laharpe
*'' Juncus andersonii'' Buchenau
*'' Juncus andinus'' Balslev
*'' Juncus antarcticus'' Hook.f.
*'' Juncus anthelatus'' (Wiegand) R.E.Brooks & Whittem.
*'' Juncus arcticus'' Willd.
*'' Juncus aridicola'' L.A.S.Johnson
*'' Juncus articulatus'' L.
*'' Juncus astreptus'' L.A.S.Johnson
*'' Juncus atratus'' Krock.
*'' Juncus australis'' Hook.f.
*'' Juncus austrobrasiliensis'' Balslev
*'' Juncus baekdusanensis'' M.Kim
*'' Juncus balticus'' Willd.
*'' Juncus bassianus'' L.A.S.Johnson
*'' Juncus batrachium'' Veldkamp
*'' Juncus benghalensis'' Kunth
*'' Juncus beringensis'' Buchenau
*'' Juncus biflorus'' Elliott
*'' Juncus biglumis'' L.
*'' Juncus biglumoides'' H.Hara
*'' Juncus bolanderi'' Engelm.
*'' Juncus brachycarpus'' Engelm.
*'' Juncus brachycephalus'' (Engelm.) Buchenau
*'' Juncus brachyphyllus'' Wiegand
*'' Juncus brachyspathus'' Maxim.
*'' Juncus brachystigma'' Sam.
*'' Juncus brasiliensis'' Breistr.
*'' Juncus brevibracteus'' L.A.S.Johnson
*'' Juncus brevicaudatus'' (Engelm.) Fernald
*'' Juncus breviculmis'' Balslev
*'' Juncus breweri'' Engelm.
*'' Juncus × brueggeri'' Domin
*'' Juncus bryoides'' F.J.Herm.
*'' Juncus bryophilus'' W.W.Sm.
*'' Juncus bufonius'' L.
*'' Juncus bulbosus'' L.
*'' Juncus burkartii'' Barros
*'' Juncus caesariensis'' Coville
*'' Juncus caespiticius'' E.Mey.
*'' Juncus canadensis'' J.Gay ex Laharpe
*'' Juncus capensis'' Thunb.
*'' Juncus capillaceus'' Lam.
*'' Juncus capillaris'' F.J.Herm.
*'' Juncus capitatus'' Weigel
*'' Juncus castaneus'' Sm.
*'' Juncus cephalostigma'' Sam.
*'' Juncus cephalotes'' Thunb.
*'' Juncus chiapasensis'' Balslev
*'' Juncus chlorocephalus'' Engelm.
*'' Juncus chrysocarpus'' Buchenau
*'' Juncus clarkei'' Buchenau
*'' Juncus compressus'' Jacq.
*'' Juncus concinnus'' D.Don
*'' Juncus concolor'' Sam.
*'' Juncus confusus'' Coville
*'' Juncus conglomeratus'' L.
*'' Juncus continuus'' L.A.S.Johnson
*'' Juncus cooperi'' Engelm.
*'' Juncus cordobensis'' Barros
*'' Juncus coriaceus'' Mack.
*'' Juncus × correctus'' Steud.
*'' Juncus covillei'' Piper
*'' Juncus crassistylus'' A.Camus
*'' Juncus curtisiae'' L.A.S.Johnson
*'' Juncus curvatus'' Buchenau
*'' Juncus cyperoides'' Laharpe
*'' Juncus debilis'' A.Gray
*'' Juncus decipiens'' (Buchenau) Nakai
*'' Juncus × degenianus'' Boros
*'' Juncus densiflorus'' Kunth
*'' Juncus deosaicus'' Noltie
*'' Juncus diastrophanthus'' Buchenau
*'' Juncus dichotomus'' Elliott
*'' Juncus diemii'' Barros
*'' Juncus diffusissimus'' Buckley
*'' Juncus × diffusus'' Hoppe
*'' Juncus digitatus'' C.W.Witham & Zika
*'' Juncus distegus'' Edgar
*'' Juncus dolichanthus'' L.A.S.Johnson
*'' Juncus dongchuanensis'' K.F.Wu
*'' Juncus × donyanae'' Fern.-Carv.
*'' Juncus dregeanus'' Kunth
*'' Juncus drummondii'' E.Mey.
*'' Juncus dubius'' Engelm.
*'' Juncus dudleyi'' Wiegand
*'' Juncus dulongjiongensis'' Novikov
*'' Juncus durus'' L.A.S.Johnson & K.L.Wilson
*'' Juncus duthiei'' (C.B.Clarke) Noltie
*'' Juncus ebracteatus'' E.Mey.
*'' Juncus echinocephalus'' Balslev
*'' Juncus ecuadoriensis'' Balslev
*'' Juncus edgariae'' L.A.S.Johnson & K.L.Wilson
*'' Juncus effusus'' L.
*'' Juncus elbrusicus'' Galushko
*'' Juncus elliottii'' Chapm.
*'' Juncus emmanuelis'' A.Fern. & J.G.García
*'' Juncus engleri'' Buchenau
*'' Juncus ensifolius'' Wikstr.
*'' Juncus equisetinus'' Proskur.
*'' Juncus ernesti-barrosi'' Barros
*'' Juncus exiguus'' (Fernald & Wiegand) Lint ex Snogerup & P.F.Zika
*'' Juncus exsertus'' Buchenau
*'' Juncus falcatus'' E.Mey.
*'' Juncus × fallax'' Trab.
*'' Juncus fascinatus'' (M.C.Johnst.) W.M.Knapp
*'' Juncus fauriei'' H.Lév. & Vaniot
*'' Juncus fauriensis'' Buchenau
*'' Juncus fernandez-carvajaliae'' Romero Zarco & Arán
*'' Juncus filicaulis'' Buchenau
*'' Juncus filiformis'' L.
*'' Juncus filipendulus'' Buckley
*'' Juncus fimbristyloides'' Noltie
*'' Juncus firmus'' L.A.S.Johnson
*'' Juncus flavidus'' L.A.S.Johnson
*'' Juncus fockei'' Buchenau
*'' Juncus foliosus'' Desf.
*'' Juncus fominii'' Zoz
*'' Juncus fontanesii'' J.Gay ex Laharpe
*'' Juncus fugongensis'' S.Y.Bao
*'' Juncus × fulvescens'' Fernald
*'' Juncus ganeshii'' Miyam. & H.Ohba
*'' Juncus georgianus'' Coville
*'' Juncus gerardi'' Loisel.
*'' Juncus giganteus'' Sam.
*'' Juncus glaucoturgidus'' Noltie
*'' Juncus gonggae'' Miyam. & H.Ohba
*'' Juncus × gracilescens'' F.J.Herm. ex Wadmond
*'' Juncus gracilicaulis'' A.Camus
*'' Juncus gracillimus'' (Buchenau) V.I.Krecz. & Gontsch.
*'' Juncus greenei'' Oakes & Tuck.
*'' Juncus gregiflorus'' L.A.S.Johnson
*'' Juncus grisebachii'' Buchenau
*'' Juncus guadeloupensis'' Buchenau & Urb.
*'' Juncus gubanovii'' Novikov
*'' Juncus gymnocarpus'' Coville
*'' Juncus haenkei'' E.Mey.
*'' Juncus hallii'' Engelm.
*'' Juncus harae'' Miyam. & H.Ohba
*'' Juncus heldreichianus'' T.Marsson ex Parl.
*'' Juncus hemiendytus'' F.J.Herm.
*'' Juncus heptopotamicus'' V.I.Krecz. & Gontsch.
*'' Juncus hesperius'' (Piper) Lint
*'' Juncus heterophyllus'' Dufour
*'' Juncus himalensis'' Klotzsch
*'' Juncus holoschoenus'' R.Br.
*'' Juncus homalocaulis'' F.Muell. ex Benth.
*'' Juncus howellii'' F.J.Herm.
*'' Juncus hybridus'' Brot.
*'' Juncus hydrophilus'' Noltie
*'' Juncus imbricatus'' Laharpe
*'' Juncus inflexus'' L.
*'' Juncus ingens'' N.A.Wakef.
*'' Juncus interior'' Wiegand
*'' Juncus × inundatus'' Drejer
*'' Juncus jacquinii'' L.
*'' Juncus jaxarticus'' V.I.Krecz. & Gontsch.
*'' Juncus jinpingensis'' S.Y.Bao
*'' Juncus kelloggii'' Engelm.
*'' Juncus khasiensis'' Buchenau
*'' Juncus kingii'' Rendle
*'' Juncus kleinii'' Barros
*'' Juncus krameri'' Franch. & Sav.
*'' Juncus kraussii'' Hochst.
*'' Juncus kuohii'' M.J.Jung
*'' Juncus laccatus'' P.F.Zika
*'' Juncus laeviusculus'' L.A.S.Johnson
*'' Juncus lancangensis'' Y.Y.Qian
*'' Juncus × langii'' Erdner
*'' Juncus leiospermus'' F.J.Herm.
*'' Juncus × lemieuxii'' B.Boivin
*'' Juncus leptospermus'' Buchenau
*'' Juncus lesueurii'' Bol.
*'' Juncus leucanthus'' Royle ex D.Don
*'' Juncus leucomelas'' Royle ex D.Don
*'' Juncus liebmannii'' J.F.Macbr.
*'' Juncus littoralis'' C.A.Mey.
*'' Juncus llanquihuensis'' Barros
*'' Juncus lomatophyllus'' Spreng.
*'' Juncus longiflorus'' (A.Camus) Noltie
*'' Juncus longii'' Fernald
*'' Juncus longirostris'' Kuvaev
*'' Juncus longistamineus'' A.Camus
*'' Juncus longistylis'' Torr.
*'' Juncus luciensis'' Ertter
*'' Juncus luzuliformis'' Franch.
*'' Juncus macrandrus'' Coville
*'' Juncus macrantherus'' V.I.Krecz. & Gontsch.
*'' Juncus macrophyllus'' Coville
*'' Juncus marginatus'' Rostk.
*'' Juncus maritimus'' Lam.
*'' Juncus maroccanus'' Kirschner
*'' Juncus maximowiczii'' Buchenau
*'' Juncus megacephalus'' M.A.Curtis
*'' Juncus megalophyllus'' S.Y.Bao
*'' Juncus meianthus'' L.A.S.Johnson ex K.L.Wilson
*'' Juncus membranaceus'' Royle
*'' Juncus mertensianus'' Bong.
*'' Juncus micranthus'' Schrad. ex E.Mey.
*'' Juncus microcephalus'' Kunth
*'' Juncus milashanensis'' A.M.Lu & Z.Y.Zhang
*'' Juncus militaris'' Bigelow
*'' Juncus minimus'' Buchenau
*'' Juncus minutulus'' (Albert & Jahand.) Prain
*'' Juncus modicus'' N.E.Br.
*'' Juncus mollis'' L.A.S.Johnson
*'' Juncus × montellii'' Vierh.
*'' Juncus × montserratensis'' Marcet
*'' Juncus × murbeckii'' Sagorski
*'' Juncus mustangensis'' Miyam. & H.Ohba
*'' Juncus nepalicus'' Miyam. & H.Ohba
*'' Juncus nevadensis'' S.Watson
*'' Juncus nodatus'' Coville
*'' Juncus × nodosiformis'' Fernald
*'' Juncus nodosus'' L.
*'' Juncus novae-zelandiae'' Hook.f.
*'' Juncus nupela'' Veldkamp
*'' Juncus obliquus'' Adamson
*'' Juncus × obotritorum'' Rothm.
*'' Juncus occidentalis'' Wiegand
*'' Juncus ochraceus'' Buchenau
*'' Juncus ochrocoleus'' L.A.S.Johnson
*'' Juncus orchonicus'' Novikov
*'' Juncus × oronensis'' Fernald
*'' Juncus orthophyllus'' Coville
*'' Juncus oxycarpus'' E.Mey. ex Kunth
*'' Juncus oxymeris'' Engelm.
*'' Juncus pallescens'' Lam.
*'' Juncus pallidus'' R.Br.
*'' Juncus paludosus'' E.L.Bridges & Orzell
*'' Juncus papillosus'' Franch. & Sav.
*'' Juncus parryi'' Engelm.
*'' Juncus patens'' E.Mey.
*'' Juncus pauciflorus'' R.Br.
*'' Juncus pelocarpus'' E.Mey.
*'' Juncus perpusillus'' Sam.
*'' Juncus persicus'' Boiss.
*'' Juncus pervetus'' Fernald
*'' Juncus petrophilus'' Miyam.
*'' Juncus phaeanthus'' L.A.S.Johnson
*'' Juncus phaeocephalus'' Engelm.
*'' Juncus pictus'' Steud.
*'' Juncus planifolius'' R.Br.
*'' Juncus polyanthemus'' Buchenau
*'' Juncus polycephalus'' Michx.
*'' Juncus potaninii'' Buchenau
*'' Juncus prismatocarpus'' R.Br.
*'' Juncus procerus'' E.Mey.
*'' Juncus prominens'' (Buchenau) Miyabe & Kudô
*'' Juncus przewalskii'' Buchenau
*'' Juncus psammophilus'' L.A.S.Johnson
*'' Juncus punctorius'' L.f.
*'' Juncus pusillus'' Buchenau
*'' Juncus pygmaeus'' Rich. ex Thuill.
*'' Juncus pylaei'' Laharpe
*'' Juncus radula'' Buchenau
*'' Juncus ramboi'' Barros
*'' Juncus ranarius'' Songeon & E.P.Perrier
*'' Juncus ratkowskyanus'' L.A.S.Johnson
*'' Juncus rechingeri'' Snogerup
*'' Juncus regelii'' Buchenau
*'' Juncus remotiflorus'' L.A.S.Johnson
*'' Juncus repens'' Michx.
*'' Juncus requienii'' Parl.
*'' Juncus revolutus'' R.Br.
*'' Juncus rigidus'' Desf.
*'' Juncus roemerianus'' Scheele
*'' Juncus rohtangensis'' Goel & Aswal
*'' Juncus × ruhmeri'' Asch. & Graebn.
*'' Juncus rupestris'' Kunth
*'' Juncus × sallandiae'' Corporaal & Schaminée
*'' Juncus salsuginosus'' Turcz. ex C.A.Mey.
*'' Juncus sandwithii'' Lourteig
*'' Juncus sarophorus'' L.A.S.Johnson
*'' Juncus saximontanus'' A.Nelson
*'' Juncus scabriusculus'' Kunth
*'' Juncus scheuchzerioides'' Gaudich.
*'' Juncus scirpoides'' Lam.
*'' Juncus secundus'' P.Beauv. ex Poir.
*'' Juncus semisolidus'' L.A.S.Johnson
*'' Juncus setchuensis'' Buchenau
*'' Juncus sherei'' Miyam. & H.Ohba
*'' Juncus sikkimensis'' Hook.f.
*'' Juncus socotranus'' (Buchenau) Snogerup
*'' Juncus sonderianus'' Buchenau
*'' Juncus soranthus'' Schrenk
*'' Juncus sorrentinoi'' Parl.
*'' Juncus sparganiifolius'' Boiss. & Kotschy ex Buchenau
*'' Juncus spectabilis'' Rendle
*'' Juncus sphacelatus'' Decne.
*'' Juncus sphaerocarpus'' Nees
*'' Juncus spumosus'' Noltie
*'' Juncus squarrosus'' L.
*'' Juncus stenopetalus'' Adamson
*'' Juncus stipulatus'' Nees & Meyen
*'' Juncus striatus'' Schousb. ex E.Mey.
*'' Juncus × stuckeyi'' Reinking
*'' Juncus stygius'' L.
*'' Juncus subcaudatus'' (Engelm.) Coville & S.F.Blake
*'' Juncus subglaucus'' L.A.S.Johnson
*''Juncus subnodulosus'' Schrank
*'' Juncus subsecundus'' N.A.Wakef.
*'' Juncus subtilis'' E.Mey.
*'' Juncus subulatus'' Forssk.
*'' Juncus subulitepalus'' Balslev
*'' Juncus supiniformis'' Engelm.
*'' Juncus taonanensis'' Satake & Kitag.
*'' Juncus tenageia'' Ehrh. ex L.f.
*'' Juncus tenuis'' Willd.
*'' Juncus texanus'' (Engelm.) Coville
*'' Juncus textilis'' Buchenau
*'' Juncus thomasii'' Ten.
*'' Juncus thompsonianus'' L.A.S.Johnson
*'' Juncus thomsonii'' Buchenau
*'' Juncus tiehmii'' Ertter
*'' Juncus tingitanus'' Maire & Weiller
*'' Juncus tobdeniorum'' Noltie
*'' Juncus torreyi'' Coville
*'' Juncus trachyphyllus'' Miyam. & H.Ohba
*'' Juncus trichophyllus'' W.W.Sm.
*'' Juncus triformis'' Engelm.
*'' Juncus triglumis'' L.
*'' Juncus trigonocarpus'' Steud.
*'' Juncus trilocularis'' Zika
*'' Juncus turkestanicus'' V.I.Krecz. & Gontsch.
*'' Juncus uncialis'' Greene
*'' Juncus uniflorus'' W.W.Sm.
*'' Juncus uruguensis'' Griseb.
*'' Juncus usitatus'' L.A.S.Johnson
*'' Juncus vaginatus'' R.Br.
*'' Juncus × valbrayi'' H.Lév.
*'' Juncus validus'' Coville
*'' Juncus valvatus'' Link
*'' Juncus vaseyi'' Engelm.
*'' Juncus venturianus'' Castillón
*'' Juncus virens'' Buchenau
*'' Juncus wallichianus'' J.Gay ex Laharpe
*'' Juncus xiphioides'' E.Mey.
*'' Juncus yui'' S.Y.Bao

References

{{Authority control

Poales genera
Taxa named by Carl Linnaeus