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1.
李延辉  张燕   《广西植物》1989,(1):25-29
<正> 多年生草本,茎细长而匍匐,节上生根。叶片膜质,近圆形或肾形,长0.5—1.5厘米,宽0.7—2.5厘米,基部心形,5—7裂,裂片阔倒卵形,边缘有钝齿,掌状脉6—8,上面疏生明显的刺状毛,下面光滑;叶柄长0.7—3厘米,无毛;托叶小,薄膜质,近肾形,具不规则的浅裂。聚伞状伞形花序通常顶生,与叶对生,有花序2—3,花序梗纤细,两侧的花序梗长达1厘米,中间的花序梗仅长1—2毫米,小总苞披针形,长约1毫米,膜质,小伞形花宇有花2—5,花无柄,花瓣卵形,长约0.5  相似文献   

2.
草本高25~30cm,基部多分枝,无根状茎。茎具沟槽,下部疏生微柔毛,上部无毛。基生叶多数,单叶或具3小叶;单叶宽心形,长2~2.9cm,宽2~2.8cm,基部心形,顶端钝,边缘具波状齿,齿具尖头,叶柄长5~8cm,几无毛;3小叶复叶比单叶长;顶生小叶宽长圆形或近椭圆形,长3~3.5cm,宽2~2.4cm,基部宽楔形或截形,顶端钝或急尖,边缘具钝齿,小叶柄长1.4~2.4cm;侧生小叶宽卵形或近圆形,长5~15mm,宽4~14mm,  相似文献   

3.
莫新礼  韦发南   《广西植物》1983,(4):307-311
<正> 蔓生或近直立草本;茎具棱,密生灰白色长硬毛。叶纸质,椭圆形或卵形,长5—9厘米,宽2.5—4厘米,先端钝,基部狭楔形,边缘有疏齿,两面被灰色长硬毛;叶柄长1—1.5厘米,被长硬毛。聚伞花序具4—5朵花,连总梗长约1.5—2.5厘米,总梗及花梗均被长硬毛;花梗长0.8—1.5厘米,花萼钟状,长5—6毫米,脉不明显,萼齿5,近等大,披针形,边缘被长硬毛;花冠白色,长约5厘米,无毛,近二唇形,上唇较短,长约3.5毫米,先端钝,下唇3裂,中裂片长圆形,长约7毫米,宽约4毫长,先端钝圆,雄蕊  相似文献   

4.
梁健英   《广西植物》1986,(4):275-276
<正> 灌木,高2—3米;树皮灰褐色;小枝紫褐色,无毛,疏生小皮孔;托叶条形,纸质,长5—7毫米。叶卵状披针形,长2.5—4.2厘米,宽1—1.5厘米,先端渐尖或尾状渐尖,基部圆楔形,有时稍不对称,边缘有锯齿,有时为重锯齿,齿端有腺体,上面无毛,下面沿中、侧脉略被毛,中脉和侧脉在上面凹陷,在下面突起,侧脉每边13—18条,网脉细密,在上面明显突起,下面不明显,叶柄长3—5毫米,无毛或被微小柔毛。果序长2—4厘米,果序轴纤细,无毛;果稀少;果苞长1—1.3厘米,半卵形或半宽卵形或长圆形,先端钝尖,外侧边缘具不规则的锯齿,内侧边缘全缘,直或微弯;小坚果宽卵形,长2.5—3毫米,宽3.5毫米,先端被柔毛,其余无毛,有明显的肋7—9条。  相似文献   

5.
多年生草本,无毛。不育茎近直立,长3—5厘米,连同花茎密生叶;花茎直立或基部横卧,基部节上生有须根,长5—10厘米。叶互生,长圆形或倒卵形,长5—8毫米,宽2.5—4毫米,先端圆钝,基部具短距。花序顶生,聚伞式蝎尾状,着生多花,常8分枝,直径2—4厘米。花为不等的五基数,无梗;萼片5,三角形和宽线形,离生,不等长,长1—2.5毫米,宽0.7—1毫米,先端钝,基部具距;花瓣5,黄色,长圆状披针形,长4.5—6.5毫米,宽1—1.5毫米,先端具短尖头,基部稍合生;雄蕊10,2轮,对瓣的长2.5—3.5毫米,在基部上1毫米处着生,对萼的长3.2—4.6毫米,花药黄褐色,鳞片5,近扇形,长约0.5毫米;心皮5,卵状披针形,全长3.5—5毫米,花柱长1—1.5毫米,基部约1毫米合生,含多数胚珠。蓇葖果成熟时星状叉开,内侧具囊状隆起。种子近卵形,长约0.6毫米,被微乳头状突起。花期6—7月。产四川南川金佛山,生于海拔1200米的山坡岩石上。本种与日本景天S.japonicum Sieb.ex Miq.相近,但植株的分枝少或无;叶扁  相似文献   

6.
张永田  李秉滔   《广西植物》1988,(1):53-55
<正> 灌木,高1—2米。当年生小枝、叶柄和花梗被细毛,老枝有时有木栓质增厚的棱,无毛。叶纸质,倒卵状椭圆形至倒卵形,长2—4.5厘米,宽1.5—2.5厘米,顶端钝、近圆形、微短尖或稀微凹,基部阔楔形至近圆形,边全缘或微背卷,两面无毛,背面灰棕色,侧脉每边3—5条,近边缘处分叉成网状消失;叶柄长2—6毫米。雄花未见,雌花1—4朵从新枝顶端或近顶端叶腋生出,花梗长约5毫米;萼片5片,卵状三角形,长约1.5毫米,被疏柔毛;子房被疏长柔毛,后无毛,3室,每室有1胚珠,花柱3枚,基部短短地合生,上部  相似文献   

7.
陈秀香   《广西植物》1988,(3):233-234
<正> 灌木,高达2米;小枝褐色,圆柱形,近无毛。叶互生,革质,圆形至卵形或卵状椭圆形,长2—5厘米,宽1.5—2.5厘米,先端圆形或钝,基部圆形或阔楔形,两面无毛,边全缘,中肋上面消凹,下面突起;侧脉不明显,3—5对;叶柄增厚,长3—4毫米,无毛;托叶微小。花单性;雌雄同株,单生于叶腋。雄花:花柄长2—2.5厘米,无毛;萼片5枚,  相似文献   

8.
李光照   《广西植物》1985,(2):85-87
<正> 深裂黄姜花 新种 图 多年生草本,茎高1—2米,直径1—3厘米;根状茎匍匐,粗壮,直径约3厘米,节间长1.5—2厘米。叶矩圆状披针形,长40—65厘米,宽7.5—13厘米,顶端长渐尖,尾状,基部急尖至阔楔形,无柄,腹面深绿色,无毛,背面略带粉绿色,疏被绢丝状柔毛;中脉在叶腹面下凹,在叶背面凸起,侧脉16—22对。叶舌干膜质,三角形至狭三角形,长2—4.5厘米,顶端圆钝,外侧密被绢丝状柔毛。穗状花序顶生,球果状,椭圆形,长15—20厘米,直径4—5厘米;苞片复瓦状排列,卵形至长卵形,绿色,长5—6厘米,宽4—5厘米,顶  相似文献   

9.
张秀实   《广西植物》1983,(4):295-306
<正> 本种极似对叶榕 F.hispida Linn.f.,但叶背面密被开展棕色糙毛,榕果(?)宽25—30毫米,无毛,成熟黄色,干后具纵沟槽,口部苞片为明显莲座状,基生苞片不明显,总花梗长5—10毫米可以区别。  相似文献   

10.
李永康   《广西植物》1985,(4):337-343
<正> 1.表腺琼楠 新种 图1 Beilschmiedia supraglandulosa Y. K. Li, sp. nov. 乔木,高5—6米;芽卵形,顶端渐尖,长4—6毫米,无毛;小枝绿色,干时褐色,明显扁压,无毛。叶薄革质,近对生,长圆状披针形,或椭圆状披针形,长7—10.5厘米,宽2.2—3.5厘米,顶端尾状渐尖,或渐尖,有长1—1.5厘米,镰状弯曲的钝尖头,基部楔  相似文献   

11.
壳斗科木材识别和分类   总被引:3,自引:0,他引:3  
谢福惠  林大新   《广西植物》1984,(3):203-213
从106种壳斗科木材构造特征.作为本科木材识别和分类依据,概括于下: 散孔材,管孔细,单个密布,在生长轮末端一狭带无管孔,宽射线为多列射线,较狭而数较多为水青冈属。辐射孔材,管孔成串径列,宽射线聚合型,在横面反光弱为主,分布不均,促使材身槽棱不整齐,槽底平而宽长的为稠属。辐射孔材,管孔成串径、斜列为主,宽射线聚合型(常见)和栎型,在横面反光强,分布均匀,促使材身槽棱整齐,槽底尖而分隔为青冈属。半环孔材或环孔材,早材管孔沿生长轮不连续排列,在肉眼下可见至明显,晚材管孔成串径列,弯曲或火焰状,宽射线聚合型,常数少且几条聚近分布,大部分树种无宽射线的为锥属。环孔材,早材管孔沿生长轮连续排列,肉眼下明显,侵填体丰富,晚材管孔成串径列,弯曲或火焰状,宽射线栎型为栎属。环孔材,早材管孔沿生长轮连续排列,肉眼下明显,具侵填体,晚材管孔成串径列,弯曲或火焰状,射线细而肉眼下不见为栗属。 各属共同特征,薄壁组织离管带状,似环管(实际为环管管胞),生长轮不同程度波状。  相似文献   

12.
论山毛榉科植物的系统发育   总被引:10,自引:2,他引:8  
本文运用分支分类学方法,对山毛榉科植物进行了系统发育的分析。山毛榉科作为单元发生群包括柯属、锥属、粟属、三棱栎属、水青冈属和栎属。桦木科和南山毛榉属被选择作为外类群。对大量的性状进行评估之后,选择了25对性状作为建立数据矩阵的基本资料。性状极化以外类群比较为主,同时也采用了化石证据和通行的形态演化的基本原则。数据矩阵由7个分类群、2个外类群和25个性状组成。采用最大同步法、演化极端结合法和综合分析法对该数据矩阵进行了分析。在得到的3个树状分支图中按照最简约的原则,选出演化长度最短的谱系分支图作为本文讨论山毛榉科属间的系统演化关系的基础。关于山毛榉科植物的系统发育,作者的观点如下:(A)现存的山毛榉科的6个属形成了4条平行进化的分支路线,它们分别被处理作4个亚科,即:栗亚科,三棱栎亚科,水青冈亚科和栎亚科;(B)平行进化是山毛榉科植物系统发育过程中的主要形式。生殖过程中的一些特征,如:果实第二年成熟,胚珠通常败育等,是影响山毛榉科植物属间基因交流的主要原因。在现存的山毛榉科植物中,柯属是最原始的类群。三棱栎属和锥属的起源也较早,而栗属、水青冈属和栎属是特化的类群。  相似文献   

13.
The taxonomic position of Castanopsis longzhouica C. C. Huang & Y. T. Chang has been controversial. Various authors included it in Castanopsis (D. Don) Spach, or Lithocarpus Bl. based on morphology, palynology and wood anatomy. In order to investigate this issue, sequences of nuclear ITS and the chloroplast genes matK and trnL-F of C. longzhouica were analyzed together with 72 representatives of 7 genera within Fagaceae. As for species of Lithocarpus , there were a 1-bp insertion and two unique 3-bp deletions from ITS2 of C. longzhouica distinguishing it from Castanopsis . The phylogenetic analyses on the separate ITS data and the joint data (ITS+ matK + trnL-F ) strongly supported a derived position of C. longzhouica within a clade consisting of members of Lithocarpus . The result is consistent with previous suggestions based on wood anatomy, suggesting that C. longzhouica should be transferred to Lithocarpus . In addition, the shallow cup-shaped, loose incoherent-scale and indehiscent cupule and the concave scar of C. longzhouica suggests a close relationship to species of Lithocarpus . Based on these data, the new combination Lithocarpus longzhouicus (C. C. Huang & Y. T. Chang) J. Q. Li & L. Chen is proposed.  相似文献   

14.
In the present paper, 3 species of Fagus, 6 of Castanea, 24 of Castanopsis, 26 of Lithocarpus, and 34 of Quercus (sens. lat.), totaling 219 specimens (slides) collected mainly from the province of Kwangtung and the vicinity have been compared, with special reference to their pore arrangement and ray disposition. Taking the Genus as a group, the macroscopic structure of each genus in detail, the end-grain photographs of the representatives and a key to the genera are provided. After comparing the wood structure, the present writer is of the opinion that it is better to correlate the genus Castanopsis Spach with the genus Lithocarpus Blume together, as has been done in some works.[2,14] In regard to the ring porosity in woody angiosperms it has a close relationships with the habitat[8,10],i.e., diffuse-porous woods usually present in evergreen trees, while ring-porous ones in deciduous trees, and of course the anatomical features too, therefore is appropriate for the genus Quercus L. to include Cyclobalanopsis (Endl.) Oerst. as a natural group.  相似文献   

15.
Wood samples of 49 specimens representing 31 species and 11 genera of woody balsaminoids, i.e., Balsaminaceae, Marcgraviaceae, Pellicieraceae, and Tetrameristaceae, were investigated using light microscopy and scanning electron microscopy. The wood structure of Marcgraviaceae, Pellicieraceae, and Tetrameristaceae is characterized by radial vessel multiples with simple perforation plates, alternate vessel pitting, apotracheal and paratracheal parenchyma, septate libriform fibers, and the presence of raphides in ray cells. Tetrameristaceae and Pellicieraceae are found to be closely related based on the occurrence of unilaterally compound vessel-ray pitting and multiseriate rays with long uniseriate ends. The narrow rays in Pelliciera are characteristic of this genus, but a broader concept of Tetrameristaceae including Pelliciera is favored. Within Marcgraviaceae, wide rays (more than five-seriate) are typical of the genus Marcgravia. Furthermore, there is evidence that the impact of altitude and habit plays an important role in the wood structure of this family. The wood structure of Balsaminaceae cannot be compared systematically with other balsaminoids because of their secondary woodiness. Balsaminaceae wood strongly differs due to the presence of exclusively upright ray cells in Impatiens niamniamensis, the absence of rays in Impatiens arguta, and the occurrence of several additional paedomorphic features in both species.  相似文献   

16.
The wood structure of 71 species representing 24 genera of the pantropical Lecythidaceae s.l., including the edible Brazil nuts (Bertholletia excelsa) and the spectacular cannon-ball tree (Couroupita guianensis), was investigated using light and scanning electron microscopy. This study focused on finding phylogenetically informative characters to help elucidate any obscure evolutionary patterns within the family. The earliest diverging subfamily Napoleonaeoideae has mixed simple/scalariform vessel perforations, scalariform vessel-ray pitting, and high multiseriate rays, all features that are also present in Scytopetaloideae. The wood structure of Napoleonaea is distinct, but its supposed close relative Crateranthus strongly resembles Scytopetaloideae. The isolated position of Foetidia (Foetidioideae) can be supported by a unique type of vessel-ray pitting that is similar in shape and size to intervessel pitting (distinctly bordered, <5 μm). The more derived Planchonioideae and Lecythidoideae share exclusively simple perforations and two types of vessel-ray pitting, but they can easily be distinguished from each other by the size of intervessel pitting, shape of body ray cells in multiseriate rays, and the type of crystalliferous axial parenchyma cells. The anatomical diversity observed is clearly correlated with differences in plant size (shrubs vs. tall trees): the percentage of scalariform perforations, as well as vessel density, and the length of vessel elements, fibers, and multiseriate rays are negatively correlated with increasing plant size, while the reverse is true for vessel diameter.  相似文献   

17.
18.
Our main goals were to identify diagnostic characters at the species, genus, and subfamily levels, find anatomical features with potential for future morphological and molecular (combined) phylogenetic analyses, and to reconstruct the evolution of wood anatomical characters in two subfamilies of Primulaceae in a molecular phylogenetic framework. We investigated twenty-seven species from the woody Myrsinoideae (4 genera) and Theophrastoideae (2 genera) using scanning electron, light, and epifluorescence microscopy. Samples were prepared using standard protocols. Based on the wood anatomical characters, we were able to identify synapomorphies and to detect evolutionary trends of interest for the genera and subfamilies. Both subfamilies share the presence of diffuse porosity, simple perforation plates, septate fibres, and scanty paratracheal axial parenchyma. Theophrastoideae species have rays?>?10 cells wide and short (<?350 µm) vessel elements, and Myrsinoideae have breakdown areas in rays and longer vessel elements. Ardisia and Stylogyne have scalariform intervessel pits, Myrsine exhibit breakdown areas in rays, and two Cybianthus species from subgenus Weilgetia have distinguishing features (e.g., scalariform perforation plate in C. nemoralis and the absence of rays in C. densiflorus). Overall, when combining characters, we were able to segregate the Neotropical Primulaceae subfamilies and genera from each other and from the subfamily Maesoideae based on wood anatomy.  相似文献   

19.
Dicotyledonous woods from the Upper Cretaceous of Southern IllinoiS. Five species of fossil dicotyledonous wood are described from an Upper Cretaceous (Maestrichtian; locality in Alexander County, IllinoiS. U.S. A. Paraquercimum cretaceum has structure similar to the Fagaceae (evergreen Oak- Lithocarpus ) and Casuarinaceae and represents the earliest known occurrence of this structural type (large solitary pores and uniseriate and large multiseriale rays). Paraphyltanthoxyhin illirioisense and Icacinoxylon alternipunctata are species of genera represented at other Cretaceous and Early Tertiary localities In large diameter trees. Parabombacaceoxylon magniporosum has large diameter pores and scalariform perforation plates, a combination of characters that is extremely rare in the extant flora. Paraapocynaceoxylon barghoorni has a combination of characters represented in extant Apocynaceae. These five species lack growth rings, have high vulnerability indices (mean vessel diameter divided by mean number of vessels per square millimeter, and a relatively high proportion of ray parenchyma. They lack specialized wood anatomical characters, and a compilation of vessel element lengths in these and other Cretaceous woods indicates that short vessel elements (a derived character) were less frequent in the Cretaceous than in extant dicotyledonous trees.  相似文献   

20.
Qiang Sun  Peng Lin 《Hydrobiologia》1997,352(1-3):61-65
We describe the wood structure of Aegiceras corniculatum and its differences under various soil salinities. This species had diffuse-porous wood with poorly defined growth rings. Vessels which had single perforations occurred abundantly and in multiples and were storeyed. Intervascular pits between contiguous vessels were alternate bordered ones while half-bordered pit-pairs existed between both vessel-ray and vessel-parenchyma. Homogenous xylem rays were multiseriate and uniseriate. Fiber-tracheids with bordered pits often had thinner walls. Xylem parenchyma cells were scant and distributed diffusely and paratracheally. Differences in the structural and quantitative characters of vessels, xylem rays and fiber-tracheids under diverse soil salinities are described. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

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