丝瓜藓属(Pohlia Hedw.)的系统位置及属内种间关系探讨

丝瓜藓属的系统地位及属内种间关系存在争议。本研究首次利用核糖体DNA内转录间区(ITS)序列数据对丝瓜藓属及相关科属植物进行系统发育分析。最大简约法,最大似然法及贝叶斯推论法构建的系统树均表明,ITS序列数据不支持将丝瓜藓属划归提灯藓科。丝瓜藓属植物与缺齿藓属植物构成一个单系分支。Brotherus(1903),Ochi(1959),Shaw(1984)及Hill等(2006)等学者提出的丝瓜藓属属下分类均不是单系类群。     

中国新记录——毛齿藓短蒴变种(新拟)

该研究首次报道了毛齿藓短蒴变种(新拟)在中国的分布和毛齿藓属在新疆的分布。研究表明：(1)毛齿藓短蒴变种的主要识别特征为：叶基部鞘状,突然狭窄成线状披针形,背仰,叶缘平展,中肋充满叶上部,背面粗糙,远轴面有厚壁细胞束分化,叶细胞长方形至短长方形;有假根生芽胞;孢蒴椭球形,稍弓形弯曲,蒴齿线状披针形,二裂至近基部。(2)毛齿藓属的3个分类单位在中国均有分布,毛齿藓短蒴变种以较短的孢蒴和蒴柄区别于原变种,以有根生芽胞、叶基部呈明显鞘状、叶缘平展区别于云南毛齿藓的无假根生芽胞、叶基部略呈鞘状、叶缘背卷。(3)在牛毛藓科中有许多类群与毛齿藓短蒴变种形态相似,但仅有毛齿藓属的叶在横切面上主细胞的远轴面有厚壁细胞束,而其他类群的叶在横切上主细胞的近轴面和远轴面均有厚壁细胞束。该变种的叶背仰不同于牛毛藓科其他属的叶直立;以具鞘部的叶、表面光滑的孢蒴、内弯的蒴齿区别于无鞘部的叶、表面有纵沟槽的孢蒴、直立的蒴齿的牛毛藓属。(4)该变种属北极 高山分布类型,表现出了明显的欧洲 亚洲 北美洲间断分布模式,可作为研究气候变化、海陆变迁的重要材料。     

中国丝瓜藓属直蒴组的分类学研究

采用经典分类学研究方法,对河北师范大学植物标本馆(HBNU)等国内多个标本馆保存的中国丝瓜藓属直蒴组(Pohlia Hedw.section Cacodon Lindb.ex Broth.)及其近缘类群植物标本共计130余号进行了分类学分析鉴定,并对所确定的中国产直蒴组物种的芽胞大小、形状及叶原基数量和长度等形态学特征进行比较分析,以期为中国丝瓜藓属直蒴组的分类学研究提供理论依据。结果表明:(1)经鉴定中国丝瓜藓属直蒴组植物共有8种——夭命丝瓜藓[Pohlia annotina(Hedw.)Lindb.]、糙枝丝瓜藓[P.camptotrachela(Ren.Card.)Broth.]、林地丝瓜藓[P.drummondii(Müll.Hal.)Andr.]、疣齿丝瓜藓[P.flexuosa Harv.]、纤毛丝瓜藓[P.hisae T.J.Kop.et J.X.Luo]、异芽丝瓜藓[P.leucostoma(BoschSande Lac.)M.Fleisch.]、念珠丝瓜藓[P.lutescens(Limpr.)H.Lindb.]和卵蒴丝瓜藓[P.proligera(Kindb.ex Breidl.)Lindb.ex Arnell]。(2)中国丝瓜藓属直蒴组植物的重要鉴别特征是在假根或叶腋处生有芽胞,而且芽胞形状以及叶原基形状和数量在直蒴组中存在差异,如念珠丝瓜藓具有假根生芽胞,而疣齿丝瓜藓具有两型芽胞。(3)对所鉴定的中国丝瓜藓属直蒴组8种植物的识别特征、生境及其与相近种的关系进行了详细描述,并绘制了形态特征墨线图。     

念珠丝瓜藓(缺齿藓科)形态特征及其在中国的新分布

通过对中国产丝瓜藓属Pohlia(缺齿藓科Mielichhoferiaceae)植物系统地分类学研究,对本属一具有假根生念珠状排列的芽胞的种——念珠丝瓜藓的形态解剖学特征和地理分布进行了修订,并讨论了念珠丝瓜藓的生境,以及与其相近种泛生丝瓜藓、明齿丝瓜藓和黄丝瓜藓等进行了比较分析。根据标本信息,确定念珠丝瓜藓在中国的分布由原来的5省区扩大到10省区,并绘制了该种在中国的分布图。     

真藓属（Bryum Hedw.）蒴齿形态特征及其分类学意义

通过光学显微镜和扫描电子显微镜观察了中国产真藓属（Bryum Hedw.）12种植物蒴齿的形态特征。结果显示,根据真藓属齿片的曲向可以分为近直立、齿片伸入齿条间和齿片向外反曲等3种类型。根据齿毛的有无,也可分为3个类群。同时利用STATISTICA 6.0统计软件对12种真藓属植物进行聚类分析及主成分分析。研究结果显示,齿片的曲向类型、齿毛是否发育等形态特征可作为真藓属植物种间的分类依据,为藓类植物蒴齿形态特征与分类和系统进化关系的研究提供了新的资料。     

青藓科（Brachytheciaceae）植物假鳞毛形态及其分类学意义

青藓科是侧蒴藓类植物中种类最为丰富、分类学问题较多的类群之一。以青藓科19属、44种，594份标本为研究对象，对其假鳞毛特征进行了系统研究。结果表明：①青藓科假鳞毛均为三角形至半圆形的叶状假鳞毛；根据其顶端特征又可划分为两种类型：顶端平截或钝，顶端具毛尖；②除青藓属（Brachythecium）外，其余18属内不同种间的假鳞毛形态基本一致；③假鳞毛形态特征在青藓科植物属级水平分类上具有一定的分类学价值。     

帕米尔木灵藓和细齿木灵藓（木灵藓科）的形态特征及其在中国的新分布

该文报道了采自新疆的木灵藓属中国2个新记录种——帕米尔木灵藓(Orthotrichum pamiricum)和细齿木灵藓(O.scanicum)。帕米尔木灵藓的识别特征为:叶尖钝,气孔隐型,多着生于孢蒴下部,外齿层齿片8对,干燥时蒴齿背曲,内齿层蒴条16,上部内曲;细齿木灵藓的识别特征为:叶尖部具细齿,气孔半隐型,蒴帽具分散的透明毛,内齿层和外齿层均16片,具8条黄色细沟,干燥时中部以上具沟。对这2种藓类的形态特征、生境和地理分布及与其相似种的形态学进行了比较分析,并绘制了每种的形态结构墨线图。木灵藓属植物在中国的新分布记录进一步表明,新疆地区富含生物多样性,并与中亚植物区系存在密切关系。     

中国新疆柳叶藓科、青藓科和灰藓科植物区系研究

通过对新疆柳叶藓科(Amblystegiaceae)、青藓科(Brachytheciaceae)和灰藓科(Hypnaceae)植物标本的野外采集和室内鉴定,报道了中国新疆地区柳叶藓科15属33种,青藓科12属51种,灰藓科11属30种,共计38属114种。其中,中国青藓科新记录种2种,新疆新记录4属37种。优势属10个,且以青藓属(Brachythecium BrushSchimp.)为代表的北温带成分为主;单种属19个,体现了新疆藓类植物区系的古老性和多样性。新疆3科藓类植物区系成分可划分为9种类型,其中北温带成分居主导地位,占中国新疆3科藓类植物总种数的52.08%,东亚成分次之,占25.01%,热带成分甚微。对中国新疆与中国内蒙古、中国西藏以及俄罗斯、蒙古、哈萨克斯坦、巴基斯坦和印度7个邻近地区的区系比较发现,印度物种丰富度最高,俄罗斯和中国新疆次之;中国新疆与中国内蒙古、俄罗斯在物种组成上相似度最高。地理成分区系谱及聚类分析结果表明,中国新疆与中国内蒙古地区的植物区系关系最为接近,而且与俄罗斯密切相关。     

木灵藓科分类与系统学研究：历史、问题和展望

木灵藓科(Orthotrichaceae)是藓类植物中的第3大科。该科不仅种类多, 生态类型特殊, 而且是世界公认的多样化程度高、分类难度大、系统关系复杂的类群。当代木灵藓科植物分类系统学研究主要集中在该科的地区志编写和专属分类修订。目前, 除了热带美洲、热带非洲的变齿藓属(Zygodon)和火藓属(Schlotheimia)部分类群外, 木灵藓科主要类群的分类修订工作已基本完成, 但是有关亚科和属的划分和地位以及各属之间的关系等方面仍存在众多争议。木灵藓科分支系统学研究也不够系统全面, 有的仅应用了单个基因片段, 或者只涉及少数类群。因此, 需要基于更多的分子和形态学性状, 进一步开展世界木灵藓科植物的系统发育研究, 建立一个更趋自然的木灵藓科分类系统。     

16种丛藓科（Pottiaceae）植物蒴齿形态特征及其系统学意义

通过扫描电镜（SEM）观察了16种国产丛藓科（Pottiaceae）植物蒴齿的形态特征,结果表明：丛藓科植物的蒴齿为单齿类,齿条1~3回左旋或直立,多具基膜,并密被疣,这些共同特征说明了丛藓科植物蒴齿具有一定的相似性;但在齿条形状和旋转情况及基膜特征等方面又有区别,明显分为3种类型,显示了不同属、种间的遗传分化。最后,本文还讨论了蒴齿特征与干旱环境的适应。     

基于核核糖体DNA ITS序列的真藓科系统发育新证据

主要是利用核基因组的核糖体DNA内转录间隔区（nrDNA ITS）序列数据探讨了Buck和Goffinet（2000）限定的真藓科内各属间及属内种间的系统发育关系。ITS序列的最大简约法（MP）及贝叶斯推论（BI）分析结果显示：不支持Cox（1999）利用rps4/trnL-trnF数据分析将丝瓜藓属移至提灯藓科的结论。ITS数据分析与Holyoak（2007）利用trnL-F,trnG和atpB-rbcL序列数据分析将Bryum algovicum、B.caespiticium、B.capillare、B.pseudotriquetrum和Plagiobryum zierii划归Ptychostomum的结论一致,同时,为Spence(2005)依据形态学特征将B.pallescen、B.pallens、B.uliginosum、B.amblyodon和B.lonchocaulon划归Ptychostomum提供ITS分子证据支持。基于以上研究,建议将以上提到的真藓属种和平蒴藓移至Ptychostomum。     

Preliminary study on phylogenetic position and delimitation of the ciliate arthrodontous genera of the moss family Mniaceae

The history of the generic and sectional concepts in the traditional moss family Mniaceae is summarised. The division of the Mniaceae into nine genera has been generally accepted. A phylogenetic analysis, based on 35 Mniaceae samples as ingroup and one Leptostomataceae and three Bryaceae samples as outgroups was completed. A total of 113 new sequences were obtained and 4139 aligned characters were included in the combined dataset. Bayesian inferences based on the combined data set showed five well supported clades, which, as a whole, form the monophyletic family Mniaceae. The number of genera in the traditional Mniaceae is 9 and the number of species is 74. All the genera appear monophyletic except Plagiomnium; accepting Orthomnion at the generic level makes Plagiomnium paraphyletic. The principle that only monophyletic taxa are allowed and may be named necessitates the uniting of Plagiomnium and Orthomnion. The necessary combinations are made. The taxonomy of the genera and sections is discussed. Rhizomnium section Macromnium T.J.Kop. & Y.Sun, sect. nov. is described and the new combination Rhizomnium chlorophyllosum (Kindb.) T.J.Kop. is made. The controversy of paraphyly – monophyly in accepting and naming taxa is discussed and Plagiomnium versus Orthomnion given as an example. All the present genera and species seem to have diverged in the area of the Laurasian supercontinent and the speciation of most genera took place in the temperate forested areas of western and eastern North America, Europe and south-eastern Asia.     

Phylogenetic relationships of Ruteae (Rutaceae): new evidence from the chloroplast genome and comparisons with non-molecular data

Phylogenetic analyses of three cpDNA markers (matK, rpl16, and trnL–trnF) were performed to evaluate previous treatments of Ruteae based on morphology and phytochemistry that contradicted each other, especially regarding the taxonomic status of Haplophyllum and Dictamnus. Trees derived from morphological, phytochemical, and molecular datasets of Ruteae were then compared to look for possible patterns of agreement among them. Furthermore, non-molecular characters were mapped on the molecular phylogeny to identify uniquely derived states and patterns of homoplasy in the morphological and phytochemical datasets. The phylogenetic analyses determined that Haplophyllum and Ruta form reciprocally exclusive monophyletic groups and that Dictamnus is not closely related to the other genera of Ruteae. The different types of datasets were partly incongruent with each other. The discordant phylogenetic patterns between the phytochemical and molecular trees might be best explained in terms of convergence in secondary chemical compounds. Finally, only a few non-molecular synapomorphies provided support for the clades of the molecular tree, while most of the morphological characters traditionally used for taxonomic purposes were found to be homoplasious. Within the context of the phylogenetic relationships supported by molecular data, Ruta, the type genus for the family, can only be diagnosed by using a combination of plesiomorphic, homoplasious, and autapomorphic morphological character states.     

Extensive length variation in the cpDNA trnT-trnF region of hemiparasitic Pedicularis and its phylogenetic implications

The cpDNA trnT-trnF region, a molecular marker widely used in the phylogenetic reconstruction at lower taxonomic levels, is relatively conserved in size and structure. In this region single length variation over 100 bp is much less common than small deletion for congeneric species of angiosperms. Here we examined evolutionary patterns of the trnT-trnF region in 43 species of Pedicularis, a species-rich genus with adaptive radiation. Four independent large deletions, varying from 203 to 297 bp in length, were detected from nine species of the genus, which might result from slipped-strand mispairing. These deletions occurred in different locations of the cpDNA region and in different clades of the phylogenetic tree, indicating that the deletion of large cpDNA fragments may be very frequent in the hemiparasitic lineage of the family Orobanchaceae. Parsimony analyses showed that section Cyathophora of Pedicularis, endemic to the Sino-Himalayan region, was a strongly supported monophyletic group. This section could have a recent origin followed by rapid radiation, considering that it is characterized by a large deletion in the trnT-trnF region and a relatively low interspecific sequence divergence.     

A tribute to Dr Royce E. Longton

Abstract

The relationships within the Bryaceae, with emphasis on the genus Bryum, were studied based on morphological and anatomical characters and using cladistic methods. The analysis was performed with thirty-six species representing the different parts of the family, and with Funaria hygrometrica Hedw., Mnium hornum (Dicks.) Lindb., and Tayloria lingulata Hedw. as outgroups. The Bryaceae, and the subfamilies Bryoideae, Mielichhoferioideae, and Pohlioideae, as defined by several earlier authors appear to be paraphyletic. The genus Bryum seems to be paraphyletic, because Leptobryum pyriforme (Hedw.) Wils., Osculatia columbica De Not., and Rhodobryum giganteum (Schwaegr.) Paris, appear as ingroups within this genus when the tree is rooted with Funaria. Mnium hornum came out as the sister taxon of a clade including Pohlia cruda (Hedw.) Lindb. and P. longicollis (Hedw.) Lindb., whereas P. drummondii (Müll. Hall.) A.L. Andrews, appears not to be closely related to the other two Pohlia species studied here, making this genus paraphyletic. Mielichhoferia mielichhoferiana (Funck.) Loeske, appears as the sister taxon of Schizymenium bryoides Harv., suggesting that both these genera are paraphyletic. Overall, the stabilities of the clades are low and it is suggested that combined analyses of morphological, anatomical, and molecular data are needed to get better resolved and more stable trees.     

Phylogeny of Carpinus and subfamily Coryloideae (Betulaceae) based on chloroplast and nuclear ribosomal sequence data

Phylogenetic studies were conducted for Carpinus and the subfamily Coryloideae (Betulaceae) using sequences of the chloroplast matK gene, the trnL-trnF region (trnL intron, and trnL [UAA] 3' exon-trnF [GAA] intergenic spacer) and the psbA-trnH intergenic spacer, and the nuclear ribosomal ITS regions. The combined analyses of the three chloroplast regions suggest that Coryloideae is monophyletic; Ostryopsis is sister to the Carpinus - Ostrya clade; Corylus is monophyletic and sister to the Ostrya - Carpinus - Ostryopsis clade; Ostrya is paraphyletic; and within Carpinus, species of sect. Carpinus from eastern Asia form a monophyletic group, whereas the positions of C. betulus from Europe and C. caroliniana from eastern North America are unresolved within the Carpinus clade. The cpDNA tree generated in this study is largely congruent with the previously published ITS results, but the ITS tree places Carpinus sect. Distegocarpus as sister to the Ostrya - Carpinus sect. Carpinus clade. Future work is needed to examine the relationships within the Ostrya - Carpinus clade, evaluate the generic status of Ostrya, and test the phylogenetic position of Ostryopsis.     

Phylogenetic relationships within Luzula DC. and Juncus L. (Juncaceae): A comparison of phylogenetic signals of trnL-trnF intergenic spacer, trnL intron and rbcL plastome sequence data

Juncus and Luzula are the largest, almost cosmopolitan, genera in the Juncaceae. Relationships within Juncus and Luzula and among other genera of Juncaceae (Distichia, Marsippospermum, Oxychloë, Patosia and Rostkovia) remain incompletely resolved. RbcL sequence data resolved a part of the supraspecific phylogeny, but many clades remain polytomic. For this reason, the non‐coding cpDNA regions, trnL intron and trnL‐trnF intergenic spacer, were sequenced. We intended to create hypotheses of relationships within Juncaceae and to test the classification of the sections, but a primary goal to this study was to assess the relationships within Juncus and Luzula and to test for monophyly of groups recognized from rbcL data (especially the monophyly of genus Luzula and the Southern Hemisphere Clade (SHC)). Furthermore, we tested the influence of different rooting and ingroup composition on the tree topology. The parsimony analyses revealed several well‐supported lineages. The traditionally distinguished genus Luzula is monophyletic and Juncus is non‐monophyletic. Two subgenera of Luzula (Pterodes and Luzula) are non‐monophyletic, while subg. Marlenia forms a sister group to the whole Luzula clade (trnL‐F data set). Within Juncus, both subgenus Juncus and subgenus Agathryon are non‐monophyletic. SHC is clustered not only with the South African J. lomatophylus and J. capensis, but also together with members of the section Juncus, Caespitosi and Graminifolii. These sections form a well‐separated sister group to the SHC. Within the genera Juncus and Luzula, monophyly is demonstrated for a number of groups (e.g., Juncus section Stygiopsis, Luzula section Luzula) but questioned for others (e.g., Juncus section Graminifolii). The unusual, separate positioning of Juncus trifidus and J. monanthos were clarified by trnL‐trnF sequence data, but vary within the tree topology depending on outgroup selection and also due to LBA phenomenon. © The Willi Hennig Society 2006.     

Using molecular data to test the monophyly of Lallemantia in the subtribe Nepetinae (Mentheae,Lamiaceae)

Phylogenetic relationships among the species of Lallemantia and its close allies (Lamiaceae, Mentheae) were investigated using nuclear (ITS) and plastid (trnL, trnL/F, trnS/G, rpl32, and rpl32-trnL) DNA sequences. Phylogenetic results from Bayesian and parsimony analyses show that (1) Lallemantia is monophyletic, (2) Hymenocrater is nested within Nepeta, and (3) Lallemantia is more closely related to Dracocephalum than other genera in Nepetinae. Based on the molecular results, the genus Lallemantia comprises two disparate lineages, with each lineage supported by distinct morphological characters (e.g. floral structures and pollen grains).     

Phylogenetics of Quiinaceae (Malpighiales): evidence from trnL-trnF sequence data and morphology

We present the first parsimony analyses of the Neotropical family Quiinaceae using nucleotide sequence data from the non-coding trnL intron and trnL-trnF intergenic spacer of the plastid genome, analysed separately as well as in combination with morphology. Both molecules and combined data recover Quiinaceae as a well-supported monophyletic group. Quiinaceae form a polytomy together with their potential sister groups, the monophyletic Ochnaceae s.str. and the monotypic Medusagynaceae from the Seychelles in the Indian Ocean. Froesia is resolved as sister to the rest of the family. Other members of the family, Lacunaria, Quiina, and Touroulia, are all recovered as monophyletic despite the inclusion of strikingly distinctive representatives (L. oppositifolia and Q. pteridophylla). Relationships among the last three genera, however, are yet uncertain. Optimising characters of breeding system onto the molecular phylogeny reveals that bisexual flowers (Froesia) are the ancestral state in Quiinaceae, whereas androdioecy (Quiina, Touroulia) and dioecy (Lacunaria) are derived breeding systems.