Studies On Taxonomy And Flora Of Hypnaceae (Musci) In Inner Mongolia, China

The Hypnaceae is a big family of pleurocarps,including about 60 genera, distributing worldwide in many kinds of substrates.The Hypnaceae are one of the most diversified moss groups.There are many concepts for the delimination, subdivision,and infrafarnilial relationships of the family.Through the systematic research of the Hypnaceae in Inner Mongolia,on the one hand,the species composition and phytogeographical compositions will be known,which will enrich data for bryoflora research in China,on the other hand,the basic information of the Hypnaceae syatematic evelution will be supplied,furthermore,the researchful results are an important composition of plant biodiversity in Inner Mongolia,offering theoretical basis for exploitation and utilizing of its plant resources.Based on field investigation,collection of specimens,and books and literatures about mosses,the author made a systematic study on the Hypnaceae in this area,15 genera and 33 species(including 1 variety and 2 forma) were identified.Among which,1 genus and 3 species are newly recorded in China,1 genus and 4 species are are new to Inner Mongolia.The author made morphological description to the taxa, drawed pictures of new recorded species. In order to know more about the bryoflora in this region and its relationships to those of the correlated areas including Yunnan,Hengduan MTS,Qinling,Hebei, Xizhang,Dongbei,Xinjiang,Shandong and Henan,the author compared the species abundance,the generic similarity coefficient,the phytogeographical elements,and analyzed the floristic spectrum using the method of Principal Component Analysis (PCA).The conclusions are as follows:The dominant phytogeographical composition is North temperate element(63.636%),and Temperate Asian element listed at the second(18.75%).This result reflects the temperate zone of this region, which is consistent with its geographical position and distribution of Spermatophyte. High similarities were found between the bryoflora in this area and that in Hebei,Which relate to their geographical location and climatic condition. Comparision and analysis about the Hypnaceae in 12 districts are conducted.With the development of recent bryophyte molecular phylogenesis,the mature of cladistics,as well as the emergence of biological software,combining the traditional taxonomy with molecular information and cladistic data,have an important meaning to elucidate the phylogeny of morphologically diverse Hypnaceae. phylogenetic analysis based on the internal transcribed spacers(ITS) of 18S-26S rDNA and the ribosome protein system 4 of chloroplast(rps4)have been conducted using maximum parsimony method(MP)and neighbor joining method(NJ).Based on 30 morphological characters,33 speices of the Hypnaceae were cladistically analyzed using maximum parsimony method(MP).The results are as following:(1)molecular studies suggest that the Hypnaceae as well as its type genus Hypnum Hedw itself are polyphyletic,and cladistic data also support Hypnum Hedw itself is polyphyletic.(2) Homornallium(Scjimp.) Loesk.is close to Pylaisiella Kindb.ex Grout.,â… agree with Fleischer's idea and put the Homomallium(Scjimp.) Loesk.,along with Platygyrium B.S.G.,Pylaisiella Kindb.ex Grout.in the subfamily Pylaisioideae.(3)Both the molecular data and the cladistic data show that some species of Gollania Broth. composing sister clades and this genus may be monophyletic;phylogenetic tree by MP method(100%)with ITS sequence and cladistic data well support that some species of this genus composing sister clades and this genus may be monophyletic;cladistic data favor Taxiphyllum taxiramenu and Taxiphyllum giraldii composing a sister clade,â… coud not conclude whether these genera are monophyletic bacause of insufficent information.For further discussions,additions of other gene sequence are needed.(4)molecular data indicate that some species of Hypnum Hedw are closely related to Breidleria Loeske,Pseudostereodon(Broth.) Fleisch.,Ptilium De Not.,Ctenidium(Schimp.) Mitt.,Eurohypnum Ando.phylogenetic tree by MP(75%) and NJ(82%) method with rps4 sequence support that Taxiphyllum taxiramenu and Hondaella caperata are sister clade.(5) phylogenetic tree by MP(75%) and NJ(82%) method withITS sequence indicate that Isopterygiopsis pulchella and Taxiphyllum taxiramenu are sister clade.(6) cladistic data also show that the above mentioned two species have some relations.(7)rps4 sequence,ITSsequence as well clatistic data have some value in discussing the phylogeny between genera within familia of mosses,some conclusions gained are consistent with the achievements in traditional taxonomy.unless molecular data,clatistic data and the traditional taxonomy are combined will they not help the development of the phylogenesis.