【作者】 林秦文；

【导师】 张志翔；

【作者基本信息】 北京林业大学 ， 野生动植物保护与利用， 2009， 博士

【摘要】 假卫矛属(Microtropis Wall.ex Meissner)为卫矛科(Celastraceae)植物,至今世界范围内记载的假卫矛属约60-70余种,分布于东亚、东南亚及中美洲温暖地区,为环太平洋间断分布。该属虽然不大,但自建立以来直到最近,一直不断有新类群发表,而该属植物形态变异复杂,花朵微小观察较难,标本材料缺乏,分类相当困难,属内植物同物异名、名实不符的问题相当常见,至今未有一个世界性的系统修订,因此对该属进行全面修订是很有必要的。本文研究馆藏腊叶标本3000余份,并在野外观察了20多个假卫矛植物居群,重点研究假卫矛属植物关键形态性状变异规律及评价其分类学意义。确认假卫矛属植物有价值的分类性状集中在花部特征,其中花序分枝式样与分枝次数、花萼形状及质地、花瓣形状、花盘的发育情况及与花瓣雄蕊的合生情况、花药的形态、子房的形状等特征具有重要的分类价值。但研究中发现假卫矛的花发育非常缓慢,花从开始发育到成熟开放历时常长达6个月以上,而不同发育阶段的花部特征常存在显著差异,有些种类中还存在雌雄异株的分化现象,这使花部特征的应用存在局限。此外,叶片的形状和质地以及果实的形状和大小在分类中也具有重要的参考价值,但同样由于生长环境和发育阶段的不同而表现出较大的变异。研究中还发现,不同的地理分布和生境下的同一个种类从叶片到花序特征各方面均可表现出较大的变异。因此,在该属的分类中,必须综合运用各方面的尽可能多的性状,而不能仅依靠少数几个性状。本文对该属的16个分类群的叶脉序特征进行了研究。发现该属的叶脉序特征整体上较为一致,均为分枝曲行羽状脉;二级脉的倾斜角度、高级脉的疏密程度在种内有较大的变异,不能作为分类依据;而二级脉的数目,直行或弧形,以及脉岛的发育情况在种间差异较大且较为稳定,可以作为分类的依据。本文对该属及相关属共5属67个分类群的叶表皮微形态进行了电镜扫描观察。发现假卫矛属及相关属植物的叶表皮角质层很厚,表皮细胞结构大都不能分辨,所有种类的气孔器均出现于下表皮,为不规则形排列。角质层纹饰可分为三种类型,一为光滑无纹饰,二为具条纹状纹饰,三为具乳突状纹饰。后两种类型仅出现在少数的种类中,为较特化的性状。叶表皮形态特征在属间没有明显的差异。本文对该属及相关属共4属39个分类群的花粉进行了电镜扫描观察。发现假卫矛属植物的花粉外观为卵圆形或长圆形,明显具三孔沟,表面具陷窝状或网眼状纹饰。多数种类的花粉仅在大小上有微小的区别,其它方面差异微小,但马来西亚地区产的一些种类的花粉相互排列紧密,形成类似花粉块的结构,单个花粉粒的外形很不规则,有较大的差异。此外,所观察的几个属植物的花粉仅在大小上有较显著的差异,其它方面差异微小。通过文献查阅、标本研究、野外考察及实验证据,本文对该属进行了较为全面的分类修订。归并了Lundell(1970)从该属独立出来的包括中美洲种类的属名Quetzalia,确认世界假卫矛属植物47种,在世界各国的大概分布情况是,中国18种,马来西亚15种,印度尼西亚8种,越南8种,印度5种,菲律宾5种,缅甸4种,泰国4种,斯里兰卡2种,墨西哥2种,日本1种,孟加拉国1种,不丹1种,哥斯达黎加1种,危地马拉1种,柬埔寨1种,老挝1种,文莱1种。描述新种3个:大围山假卫矛M.daweishanensis Q.W.Lin et Z.X.Zhang、长果假卫矛M.longicarpa Q.W.Lin et Z.X.Zhang、西藏假卫矛M.xizangensis Q.W.Lin et Z.X.Zhang,均产于中国。重新确认尖尾假卫矛M.caudata、簇果假卫矛M.fasciculata、大果假卫矛M.macrocarpa、菲律宾假卫矛M.philippinensis、红色假卫矛M.rubra、爪哇假卫矛M.javanica为独立的种,另将47个分类群名称新处理为异名。确认7个学名为非假卫矛属植物,做出新命名全缘叶沟瓣Glyptopetalum integrifolium Q.W.Lin,Z.X.Zhang et Q.R.Liu(基原异名M.poilanei Tardieu)及新组合Garcinia gagei(Merr.et Freeman)Q.W.Lin etZ.X.Zhang(基原异名M.gagei Merr.et Freeman)。确认中国记录的越南假卫矛M.fallax、大叶假卫矛M.macrophylla及淡色假卫矛M.pallens系鉴定错误,并确认大果假卫矛M.macrocarpa为中国特有的濒危物种,喙果假卫矛M.rhynchocarpa分布于广东,为中国新记录植物。此外,尚有3个名称由于缺乏材料,暂时存疑。更多还原

【Abstract】 Microtropis Wall.ex Meisner,a medium genus of the family Celastraceae,currently contains about 60-70 species in the world,which are distributing in East and Southeast Asia,and Central American.Although this is no a large genus,but from the day when it is established,the names published under this genus are numerous,but have no yet been well treated for even one time in the worldwide scale.Due to the complex of variation in the morphological characters and the difficulties of observation of the small flowers,the classification of this genus is very difficult and there are many problems in the present species under this genus.Therefore,the work to conduct a comprehensive revision of this genus is very necessary.By studying on more than 3000 sheets of specimens in herbaria and observing of more than 20 populations in fields,we tried to search and evaluate the variation patterns of morphological characters amang the Microtropis plants.The results show that the good characters for taxonomy concentrates on flowers.Inflorescence types and branching times,calyx shape and texture,petal shape, disk state and its condition with petals and stamens,anther shape,and pistil shape are the most important characters in the genus.But we also found that the development of flowers in this genus is very slow and the phase from the beginning of inflorescence primordium to mature or opening of the flowers is often more than 6 months,there are conspicuous differences of flower characters between the materials collected at different phases,and there are still pseudohermaphroditic and diecious phenomenons in some species,so the practical use of flower characters are somewhat limited.The leaf shape and texture,and the fruit shape and size are also very important characters for taxonomy, but variable due to different habitat and different developmental stages.It is noteworthy that the populations of the same species from different geographical locations often show conspicuous and gradual variation in various characters.Therefore,the taxonomy of such a genus must use as many characters as possible,can no rely on a few characters. Leaf architecture features of 16 taxa in Microtropis were studied.The results show that thegeneral features of leaf architecture are quite uniform as camptodromous pinnate venation.Intraspecific the divergence angle of secondary veins,and the density of tertiary veins or higher veins are quite variable,thus are inappropriate for species discrimination.Whereas the number and shape(straight or arcuate) of secondary veins,and the state of vein areolas are quite different and stable between different species,so can be used as characters for taxonomy.Foliar epidermis of 67 taxa in Microtropis and 4 related genera was observed with SEM.The results show that the comeous layer is very thick,the structure of epidermal cells can’t be distinguished,the stomas are irregularly arranged on the lower surface of leaves.Sculpture can be devided as 3 types,smooth,striate,and papillate.Striate sculpture and papillate sculpture are specialized characters,and only occur in a few species.Generally,there are not significant differences of foliar epidermis between the genera observed.Pollen of 39 taxa in Microtropis and 3 related genera was observed with SEM.The results show that most pollen grains observed are elliptoid,globose,or oblong at equatorial view,tricolporate, extine layer foveolate or reticulate.In most species the pollen grains are only slightly different in the size,but a few Malaysian species have specialized pollen grains which are irregular in shape and closely arranged to form structure like pollen mass.Generally,the pollen grains show not significant differences between the genera observed except the size.Finally,a taxonomic revision of the genus Microtropis worldwide was conducted,based on extensive literature survey,both herbarium and field observations,and experimental evidences.The genus Quetzalia Lundell(1970) with central American species are included in Microtropis,and total 47 species in Microtropis worldwide have been accepted,the gross distribution in the countries as following: China 18,Malaysia 15,Indonesia 8,Vietnam 8,India 5,Philippines 5,Myanmar 4,Thailands 4,Sri Lanka 2,Mexico 2,Japan 1,Bangladesh 1,Bhutan 1,Costa Rica 1,Guatemala 1,Cambodia 1,Laos 1, Brunei 1.3 new species M.daweishanensis Q.W.Lin et Z.X.Zhang,M.longicarpa Q.W.Lin et Z.X.Zhang,and M.xizangensis Q.W.Lin et Z.X.Zhang from China are described.M.caudata, M.fasciculata,M.macrocarpa,M.philippinensis,M.rubra,and M.javanica are recognized as independent species,other 47 names are reduced to synonyms.7 taxa are recognized as not Microtropis plants,in which new nomenclature Glyptopetalum integrifolium Q.W.Lin,Z.X.Zhang et Q.R.Liu(Basonym:M.poilanei Tardieu) and new combination Garcinia gagei(Merr.et Freeman) Q.W.Lin et Z.X.Zhang(Basonym:M.gagei Merr.et Freeman) were proposed. M.fallax,M.macrophylla,and M.pallens recorded in Chinese literature are confirmed as misidentification,M.macrocarpa is confirmed as endangered species endemic to China,and M.rhynchocarpa is newly record in Guangdong,China.Finally,there are still 3 names which are lack of any materials and can only be left to be done later.更多还原