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1.
A small prostrate herb, Euphorbia salsicola , a woody shrublet with curious tubers, E. scatorhiza , and a small tree with decorative bracts, E. thulinii , are described as new species of Euphorbia. Within subgenus Lyciopsis the morphological variability of E. cuneata in Somalia is discussed and a new subspecies cretacea is described. E. gypsophila , a closely related but distinct species found only on gypsum is also described as new, together with E. dunensis , a shrublet from the coastal dunes and E. tripartita , another shrub in the same subgenus related to E. matabelensis. As far as present records show, all the new taxa are endemic in Somalia.  相似文献   

2.
VENTER, H.J. T. & FIELD, D. V., 1989. A new species of Stomatostemma (Periplocaceae) from Mozambique, Africa. A new species of Stomatostemma is described from Mozambique. 11 is [he second species distinguished in the genus Stomatostemma N.E. Br., the other being S. monteiroae (Oliv.) N.E. Br., which was also described from Mozambique. The new species is distinguished from.V. monteiroae by being a virgate shrub, by the pendulous terminal branches and inflorescences, by the long and frail peduncles and pedicels and by the long clavate corona lobes.  相似文献   

3.
本文发表了石竹科一新属,假卷耳属PseudocerastiumC.Y.Wu,X.H.GuoetX.P.Zhang。该属模式种为假卷耳PseudocerastiumstellarioidesX.H.GuoetX.P.Zhang,近于卷耳属,繁缕属和鹅肠菜属。另报道一个中国地理分新分布种,异型花缕StellariadiverisfloraMaxim.。  相似文献   

4.
A new rheophytic species of Philodendron, viz. P. carajasense E. G. Gonç. & A. J. Arruda sp. nov., is described from the Carajás region, northern Brazil. This is the second rheophyte described in the genus, the first being P. flumineum E. G. Gonç. to which P. carajasense seems to be related. The new species is also compared with the closely related sympatric P. guttiferum, but the latter lacks the rheophytic habit. The new species is thought to be endemic to the Carajás region.  相似文献   

5.
A new species ofEmericella isolated from forest soil in the Oman,E. omanensis, is described and illustrated. It differs from the other known species of the genus in having bivalvate ascospores with a tuberculate or verruculose convex wall. The new species is compared with the closely related speciesE. desertorum andE. echinulata.  相似文献   

6.
Two new species ofXanthoriaare described and illustrated, and comments about their differences from related taxa are provided. These are:X. ascendensfrom bark and shrub remains in sea-shore sand dunes and hillsides in Argentina, Chile and Peru, andX. ucrainica, from bark, stones, and some man-made substrata in the Ukraine, Sweden, United Kingdom, Germany, Austria and Asian Russia.  相似文献   

7.
Kniphofia monticola Blackmore sp. nov., from Mulanje Mountain in Malawi is described. This new species is most closely related to K. splendida E. A. Bruce, a widely distributed species in tropical and southern Africa.  相似文献   

8.
Arenaria dawuensis A. J. Li&Q. Ban,a new species of the Caryophyllaceae from Dawu County,Sichuan,China,is described and illustrated. It is related to A. fimbriata(E. Pritz. )Mattf. in having fusiform roots,cymose inflorescence,two linear styles,but differ  相似文献   

9.
对产自越南的荨麻科楼梯草属植物一新种金喜楼梯草(Elatostema kimhyense Y.G.Wei & V.T.Do)作了描述和绘图。该种生长于海拔350~400和1 100~1 200 m的石灰岩山地林下。该新种与越南楼梯草(E.vietnamense Q.Lin & L.D.Duan)接近,区别在于其拥有肉质茎,羽状脉,叶背面、苞片和小苞片被微硬毛。  相似文献   

10.
A new species in theEpidendrum difforme complex is described and illustrated,E. oldemanii. Closely related toE. amapense, E. oldemanii is distinguished by the absence of a midlobe to the labellum.  相似文献   

11.
In addition to the known mutisicoumarin A, the aerial parts of the shrub Mutisia friesiana afforded five new methylphenones, two new 5-methylcoumarins and a new related chromone. Their structures were elucidated by spectroscopic methods 13C NMR data for mutisicoumarin A are reported for the first time. Mutisiphenones A and B and mutisicoumarin A showed antifungal activity against the phytopathogenic fungus Cladosporium cucumerinum.  相似文献   

12.
Aims Shrub encroachment is a common global change phenomenon occurring in arid and semi-arid regions. Due to the difficulty of partitioning evapotranspiration into shrub plants, grass plants and soil in the field, there are few studies focusing on shrub encroachment effect on the evapotranspiration and its component in China. This study aims to illustrate shrub encroachment effect on evapotranspiration by the numerical modeling method. Methods A two-source model was applied and calibrated with the measured evapotranspiration (ET) by the Bowen ratio system to simulate evapotranspiration and its component in a shrub encroachment grassland in Nei Mongol, China. Based on the calibrated model and previous shrub encroachment investigation, we set three scenarios of shrub encroachment characterized by relative shrub coverage of 5%, 15% and 30%, respectively, and quantified their effects caused by shrub encroachment through localized and calibrated two-source model. Important findings The two-source model can well reconstruct the evapotranspiration characteristics of a shrub encroachment grassland. Sensitivity analysis of the model shows that errors for the input variables and parameters have small influence on the result of partitioning evapotranspiration. The result shows that shrub encroachment has relatively small influence on the total amount of ET, but it has clear influence on the proportion of the components of evapotranspiration (E/ET). With shrub coverage increasing from 5% to 15% and then 30%, the evapotranspiration decreased from 182.97 to 180.38 and 176.72 W·m-2, decreasing amplitude values of 0.34% and 0.44%, respectively. On average, E/ET rises from 52.9% to 53.9% and 55.5%, increasing amplitude values to 2.04% and 3.25%. Data analysis indicates that shrub encroachment results in smaller soil moisture changes, but clear changes of ecosystem structure (decreasing ecosystem leaf area index while increasing vegetation height) which lead to the decrease of transpiration fraction through decreasing canopy conductance. The research highlights that, with the shrub encroachment, more water will be consumed as soil evaporation which is often regarded as invalid part of evapotranspiration and thus resulting in the decrease of water use efficiency.  相似文献   

13.
香花油茶——山茶属短柱茶组一新种   总被引:1,自引:0,他引:1  
马锦林  叶航  叶创兴 《广西植物》2012,32(6):753-755
描述了山茶属短柱茶组新种Camellia osmantha Ye CX,Ma JL et Ye H.新种为灌木,花白色,微有香气.其苞被不分化为苞片和萼片,多数,10~12枚,花瓣6~8枚,均易脱落;雄蕊长短不一,大部分分离;花柱短,基部连生,先端分离,与短柱茶组特征一致.新种花有香气与窄叶短柱茶C.fluviantlis Hand.-Mzt.接近,但前者叶常为倒卵形,具尾尖,后者叶狭披针形,渐尖.  相似文献   

14.
Abstract. The Turkish Eupholidoptera species are reviewed and a key to them provided. Five new species are described alongwith the previously unnknown male of E.excisa (Karabaĝ), and females of E.tauricola (Ramme) and E. werneri Ramme. Following examination of specimens from Cyprus the previously unknown male of E.cypria Ramme is described. A new subspecies of E.cypria is described from southern Turkey. Diagnostic characters of all species are given. A check-list and a distribution map are provided for the Turkish species of Eupholidoptera.  相似文献   

15.
王文采 《广西植物》2019,39(3):291-293
描述了自重庆南部发现的荨麻科楼梯草一新种,江津楼梯草(Elatostema jiangjinense)。此新种与锐齿楼梯草(E. cyrtandrifolium)近缘,两者的区别在于江津楼梯草的叶在狭侧具2条二级脉,托叶卵形或披针形,以及雄总苞片在顶端具长角状突起。  相似文献   

16.
PANGUA, E., PRADA, C, PAJARON, S. & SALVO, E., 1992. A new Aspleniutn hybrid from Valencia (Spain) related to A. majoricum Litard . A new diploid Asplenium hybrid, found in the Iberian Peninsula (Valencia, Benifairo de Valldigna), is described and the name Asplenium x protomajoricum proposed. The plants exhibit c. 72I at meiosis. The cytology and morphology of the hybrid and its occurrence between the assumed parentals suggest that it originated from a cross between A. fontanum and A. petrarchae subsp. bivalens. The occurrence of A. petrarchae subsp. bivalens in eastern Spain is confirmed cytologically. The occurrence of A. majoricum on the mainland is also discussed.  相似文献   

17.
Bianchinotti MV 《Mycologia》2004,96(4):911-916
Two species of Nitschkia are described from bark and wood of a legume shrub, native to the semiarid regions of Argentina. Nitschkia campylospora is characterized by asci with a variable number of ascospores, mainly 16, and curved ascospores; hairy ascomata and large ascospores are two distinct features of Nitschkia pilosa. The new species are compared with most similar species. A key to Nitschkia species is provided with the inclusion of comments on those from Argentina and neighboring countries.  相似文献   

18.
19.
Shifts between facilitation and interference and their importance in shaping plant population and community dynamics have received wide recognition. Nevertheless, the causes and spatio-temporal scales of these shifts are poorly understood, yet strongly debated. This study tested the hypothesis that age-related changes in canopy structure shift the effect of a nurse shrub on their protégé from facilitation to interference, using as a model system the interaction between the dwarf shrub Sarcopoterium spinosum and conspecific new recruits, in the shrubland of the transition area between the Mediterranean and the semi-arid climatic zones of Israel. Foliation level (i.e. the percentage of canopy surface area covered with leaves), a measure of shrub canopy structure, increased with age. Shading level was significantly and positively related to foliation level. Densities of new recruits in the shrubland showed a unimodal response to canopy structure and cover: the highest densities were associated with canopies presenting low and medium foliation levels (providing 71 and 82% shade, respectively), while high foliation levels (93% shade) and open spaces among canopies were characterized by very low densities. A related field experiment using shading nets revealed that seedling survival rates followed a similar unimodal pattern, with the highest survival (ca 60%) detected in moderate shade (70%), twice as much as in full sun, and the lowest survival (ca 10%) observed in extreme shade (90%). These results support the study hypothesis on age-dependent interactions. Thus, in a semi-arid shrubland ecosystem, the transition of the "nurse shrub" from "young" to "old" stage can shift facilitation to interference. Hence, the age structure of established shrub populations determines a) the availability of suitable sites for seedling recruitment and b) the balance between facilitation versus interference effects on seedling establishment.  相似文献   

20.
A new species, Asplundia altiscandens E. S. Leal from the Brazilian Amazon, is described and illustrated. It belongs to subgenus Asplundia and is related to A. ferruginea and A. nonoensis. Diagnostic characters, a distribution map and taxonomic comments are provided.  相似文献   

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