A Taxonomic Study Of Marchntiophyta In The East Yunnan-Guizhou Plateau

The East Yunnan-Guizhou Plateau is one of the regions with the most abundant bryophyte taxa in China.Due to the large variety and complex composition,no systematic taxonomic study has been carried out so far.Therefore,a comprehensive taxonomic study of liverworts in this region can not only reveal the diversity composition of liverworts in this region,but also serve as an important supplement to bryophyte flora and taxonomy in China.At the same time,it can fill the last vacancy in the study of higher plant species composition in southwest China.Thirdly,it has important theoretical guiding significance for further scientific research,rational development and utilization and protection of liverworts in this area.Based on classical taxonomic methods,a comprehensive examination and detailed morphological anatomy have been conducted on a large number of herbaria housed in GACP.Field supplementary investigation and collection were conducted in the key areas of the East Yunnan-Guizhou Plateau.A comprehensive taxonomic study of liverworts in this region has been completed,and the composition of species diversity and Flora patterns of liverworts in this region has been analyzed.The main research results were as follows:1.Based on the examination and morphological anatomy of more than 9000 liverwort specimens collected from the East Yunnan-Guizhou Plateau and a large number of literatures,427 taxa(including 14 varieties and 9 subspecies)belonging to 90 genera and 47 families are recognized as occurring in this area.Among them,there are 360 taxa(including 13 varieties and 7 subspecies)of leafy gametophyte in 67 genera and 29 families and 67 taxa(including 1 variety and 2 subspecies)of thallus in 22 genera and 18 families.The detailed morphological description and taxonomic discussion of most taxa are provided.There are 301 microanatomical plates(including 262 micrographic plates and 39 hand-drawn plates)are provided for 361 taxa.At the same time,the number of liverworts in this area is second only to Yunnan and Taiwan province,which is similar to the species of the neighboring Guangxi Zhuang Autonomous Region.The number of liverworts taxa in this area was second only to Yunnan Province and Taiwan Province,ranking the third in China,which is close to neighboring Guangxi Zhuang Autonomous Region.The number of liverworts taxa in this area was second only to Yunnan Province and Taiwan Province,ranking the third in China,which is close to neighboring Guangxi Zhuang Autonomous Region.The land area of this area only accounts for 1.88% of the national land area,while the number of liverworts species accounts for nearly 40.57% of the national total.2.In this study,a new variant Frullania ericoides var.planescens(Verd.)S.Hatt was merged into Frullania ericoides(Nees)Mont.3.Eighty-four taxa are newly reported to the East Yunnan-Guizhou Plateau.Among them,Mesoptychia chinensis Bakalin,Vilnet & Xiong sp.nov.is new to science;Anastrophyllum minutum var.acuminatum(Horik.)T.Cao & J.Sun and Radula lacerata Steph.are firstly discovered in mainland China;Lophozia silvicola H.Buch,Calypogeia angusta Steph.,Mesoptychia ussuriensis(Bakalin)L.S?derstr.et Vá?a,Chiastocaulon herzogii(Inoue)S.D.F.Patzak,Frullania cobrensis Gottsche,Lejeunea papilionacea Prantl,Lejeunea spiniloba Lindenb.,Porella longifolia(Steph.)S.Hatt.,Porella perrottetiana var.angustifolia Pócs,Metzgeria fukuokana Kuwahara,Moerckia flotoviana(Nees)Schiffn.and Riccia nipponica S.Hatt.are reported to China for the first time.It is worth noting that,Chiastocaulon Herzogii(Inoue)S.D.F.Patzak has not been reported since Inoue published it as a new species in 1971 based on the only specimen collected by Herzog in Sumatra,Indonesia,this discovery is the second reported distribution of this species worldwide;Frullania Cobrensis Gottsche and Lejeunea spiniloba Lindenb,which have been considered endemic to North America,are found to be disjuncted from tropical Asia to tropical America;Porella longifolia(Steph.)S.Hatt.was originally endemic to northern Sumatra,Indonesia,but it has been reported for many times in Sichuan Province,Chongqing Municipality,Yunnan Province,Tibet Autonomous Region,Guangxi Zhuang Autonomous Region and other places in China.It has since been removed from the Flora of China,and this discovery reconfirms its distribution in China;Porella Perrottetiana var.angustifolia Pócs has only been reported in northern Vietnam before,however,this variety is actually a relatively common taxon in karst areas in southwest China.In addition,Balantiopsidaceae H.Buch,Jackiellaceae R.M.Schust.,Myliaceae Schljakov,Tetralophozia(R.M.Schust.)Schljakov,Alobiellopsis R.M.Schust.,Isotachis Mitt.,Jackiella Schiffn.,Mylia Gray,Myriocoleopsis Schiffn.,Calycularia Mitt.and Moerckia Gottsche(new to China)were firstly recorded in this area.The discovery of a large number of newly distributed taxa greatly enrich the species composition of liverworts in this area and is an important supplement to the floristic composition of liverworts in this area.4.This study provides respectively a detailed description for three new recorded species in China: Chiastocaulon herzogii(Inoue)S.D.F.Patzak,Porella longifolia(Steph.)S.h.and Porella perrottetiana var.angustifolia Pócs.5.The species diversity composition of liverworts in the East Yunnan-Guizhou Plateau is analyzed,and 15 dominant families with species number ?10 are found,including Lejeuneaceae Cavers,Plagiochilaceae Müll.Frib.,Frullaniaceae Lorch,Porellaceae Cavers,Lepidoziaceae Limpr.and so on.There were 354 species(83.10%)of 50 genera(56.18%)in 15 dominant families,which constituted the dominant body of liverworts in the East Yunnan-Guizhou Plateau.Among the dominant families,Lejeuneaceae Cavers is the largest family including 14 genera and 96 taxa(It accounts for 42.67% of the species of Lejeuneaceae in China),next is Plagiochilaceae Müll.Frib.composing of 2 genera and 43 taxa(It accounts for 49.43% of the species of Plagiochilaceae in China),meanwhile,there are more than 20 taxa in Frullaniaceae Lorch,Porellaceae Cavers and Lepidoziaceae Limpr.On the other hand,there are19 dominant genera whose number of taxa ?6 are recognized,as follows: Plagiochila(Dumort.)Dumort.,Cololejeunea(Spruce)Steph.,Frullania Raddi,Porella L.,Lejeunea Lib.And so on.The largest genus is Plagiochila(Dumort.)Dumort(40 taxa),followed by Cololejeunea(Spruce)Steph.(36 taxa).In addition,there are more than 20 taxa in Frullania Raddi,Porella L.and Lejeunea Lib.And more than 10 taxa in Solenostoma Mitt.,Scapania(Dumort.)Dumort.,Bazzania Gray,Radula Dumort.and Riccardia Gray.6.The results of floristic analysis show that liverworts in this area show distinctive East Asian characteristics,with 200 species accounting for 49.26%.Among the East Asian element,83 species are from Sino-Japan,accounting for 20.44%.Meanwhile,32 species are Endemic to China,accounting for 7.88%.There were 74 Trop.Asia species and 55 North temperate species,accounting for 18.23% and 13.55% respectively in total species.These three flora patterns,including 329 species accounting for 81.03% of the total species and constituting the main component of liverwort flora in this area.