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1.
Cyclamen somalense Thulin & Warfa, spec. nova, the first member of the genus known from tropical Africa, is described from the Al Miskat Mts in NE. Somalia. The new species is closely related to the E. MediterraneanC. persicum Mill. The disjunct Mediterranean element in the mountain flora of northern Somalia, to whichC. somalense belongs, is believed to be largely a relict of Tertiary origin.  相似文献   

2.
A small succulent, spiny Euphorbia is described as a new species, E. patentispina , endemic to Somalia, with a limited distribution in the northeast region of Bari. Its relationship to other species of the same group—those producing subsessile capsules and a single spine from each spine shield—occurring in northern Somalia is discussed.  相似文献   

3.
The new species Kleinia caespitosa, from crevices in limestone rocks at 1850–1900 m in northern Somalia, is described and illustrated. It is compared to the widespread and sympatric K. grantii, as well as to K. saginata in Oman.  相似文献   

4.
The new species Boswellia globosa, from the foothills of the limestone escarpment along the Gulf of Aden in northern Somalia, and Commiphora lacerata, from a rocky limestone slope near the coast of the Indian Ocean in north‐eastern Somalia, are described and illustrated.  相似文献   

5.
Abstract

Digitaria brunoana (Gramineae), a new species from Somalia. - Digitaria brunoana, a new species occurring on the coastal sand dunes at Gesira near Mogadishu (Somalia), is described. This new taxon is related to D. longiflora which is distributed in the Tropical Africa.  相似文献   

6.
The rare Tasmanian endemic Eucalyptus risdonii is thought tohave arisen as a result of small, heterochronic changes to the genome ofits more widespread sister species, E. tenuiramis. Previousmorphological studies have shown that genetic differentiation betweenpopulations of E. risdonii and southern E. tenuiramisis continuous and much smaller than the separation between the southernand northern morphotypes of E. tenuiramis. However,morphological traits may be influenced by selection, possibly leading toconvergence, requiring an independent measure of genetic variation. Westudied allozyme frequency variation in E. risdonii, southernE. tenuiramis (parapatric with E. risdonii), northernE. tenuiramis (disjunct from southern populations), and E.coccifera (as an outgroup). Each morphotype had a level of geneticdiversity close to the average reported in ten other eucalypt specieswith similar distributions but the coefficients of populationdifferentiation within morphotypes were lower than in most othereucalypt species. The overall difference between morphotypes wasextremely small, possibly as a result of recent and rapiddifferentiation, but may also be the result of gene flow from otherpeppermint taxa, including E. amygdalina and E.pulchella. Southern E. tenuiramis has greater geneticaffinity with E. risdonii than with northern E.tenuiramis which supports recent evolutionary divergence of E.risdonii. In this study we have shown that taxonomic units are notnecessarily aligned with an equitable partition of the gene pool andthat conservation units should be much broader than single taxa in orderto preserve evolutionary processes.  相似文献   

7.
Eighteen new species of Euphorbia subgenus Euphorbia are described and their relationships discussed. All are endemic to Somalia, with limited distributions in the northern Regions. One, E. phillipsioides , has been identified mistakenly for some time as E. phillipsiae , which is shown to be conspecific with E. golisana. E. xylacantha , considered by N. E. Brown to be synonymous with E. monacantha , is reinstated as a distinct but variable species.  相似文献   

8.
9.
The taxonomy of the desert shrub genus Fagonia is revised in detail. In total 167 names are accounted for, lectotypes are selected for 33 names, and two names are neotypified. A key to the 34 species is presented, as well as distribution maps for each species. Three new species are described and illustrated, F. densispina and F. latistipulata from Somalia, and F. hadramautica from Yemen. Of the accepted species, 24 are restricted to the Old World and eight to the New World. Most of the Old World species are confined to the Saharo‐Sindian region, with two extending to parts of Macaronesia. Eight species are endemic to the Somali‐Masai region, and two are restricted to southern Africa. In the New World four species are endemic to Baja California, two to northern Baja California and adjacent parts of southwestern USA, one to the province of Coahuila in northeastern Mexico, and one to Chile and Peru. The names of all four species of Fagonia currently on the IUCN Red List of Threatened Plants are put into synonymy.  相似文献   

10.
An integrative taxonomic approach, including molecular phylogenetic reconstructions based on plastid rps4-trnF and nuclear ITS sequences, statistical analysis of morphological-anatomical characters, and classical taxonomy, indicates that the reduction of 13 Amphidium species to three in a recent morphological revision represents a case of too extensive lumping. Instead, six Amphidium species can be distinguished based on molecular and morphological data, the widespread Amphidium lapponicum, A. mougeotii, and A. tortuosum, as well as the Macaronesian endemic A. curvipes, the North American endemic A. californicum, and a newly discovered species from Central Asia (southern Siberia and northern Mongolia), A. asiaticum sp. nov. Diagnostic morphological characters for all six species are discussed. The present data confirm that species diversity of Amphidium is highest in the Holarctic, where all six species occur.  相似文献   

11.
Tetragonia pentandra , previously believed to be an endemic of Socotra, is reported from northern Somalia. T. retusa sp. nov., a very distinctive endemic of central Somalia with features that partly link Tetragonia and Tribulocarpus , is described and illustrated.  相似文献   

12.
Aim To relate genetic diversity to topographic features and to investigate genetic interactions between Eucalyptus species in a local centre of endemism and diversity in south‐eastern Australia. Location Grampian Ranges, Victoria, Australia. Methods We documented chloroplast DNA (cpDNA) variation for a group of endemic Eucalyptus species (E. serraensis, E. verrucata and E. victoriana) that dominate rocky, high‐elevation ridgelines of the Grampian Ranges and for one closely‐related, widespread species (E. baxteri) occupying flanking slopes and valleys. We documented genetic patterns across the landscape using cpDNA microsatellites, and related them to topographic features (exposed west‐facing versus protected east‐facing slopes and valleys). We also determined the extent of local haplotype sharing between populations of endemic species and neighbouring E. baxteri downslope with cpDNA microsatellites, and haplotype sharing between the endemic group and more distantly related species (E. obliqua, E. pauciflora and E. willisii) with sequences of the JLA+ chloroplast region. Results We detected 26 cpDNA microsatellite haplotypes in a relatively small area of c. 20 km × 50 km. Populations of E. baxteri on east‐facing slopes and valleys had greater cpDNA microsatellite diversity than E. baxteri and endemic species on exposed west‐facing slopes. Endemic species frequently shared chloroplast haplotypes with E. baxteri downslope. Sharing of JLA+ haplotypes with species outside the endemic group was mostly restricted to E. victoriana, which had cpDNA more similar to the species from other sections of Eucalyptus (E. obliqua, E. willisii and E. pauciflora). Main conclusions Intensive sampling of related species on small isolated mountain ranges allowed us to relate genetic diversity to fine‐scale habitats and to document extensive local haplotype sharing between species. This study contributes to a general understanding of the environmental conditions that enable plant population persistence by linking concentrations of genetic diversity to particular habitats.  相似文献   

13.
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   

14.

Background

For more than a decade, most parts of Somalia have not been under the control of any type of government. This “failure of state” is complete in the central and southern regions and most apparent in Mogadishu, which had been for a long period in the hands of warlords deploying their private militias in a battle for resources. In contrast, the northern part of Somalia has had relatively stable control under regional administrations, which are, however, not internationally recognized. The present study provides information about drug abuse among active security personnel and militia with an emphasis on regional differences in relation to the lack of central governmental control—to our knowledge the first account on this topic.

Methods and Findings

Trained local interviewers conducted a total of 8,723 interviews of armed personnel in seven convenience samples in different regions of Somalia; 587 (6.3%) respondents discontinued the interview and 12 (0.001%) were excluded for other reasons. We assessed basic sociodemographic information, self-reported khat use, and how respondents perceived the use of khat, cannabis (which includes both hashish and marijuana), psychoactive tablets (e.g., benzodiazepines), alcohol, solvents, and hemp seeds in their units. The cautious interpretation of our data suggest that sociodemographic characteristics and drug use among military personnel differ substantially between northern and southern/central Somalia. In total, 36.4% (99% confidence interval [CI] 19.3%–57.7%) of respondents reported khat use in the week before the interview, whereas in some regions of southern/central Somalia khat use, especially excessive use, was reported more frequently. Self-reported khat use differed substantially from the perceived use in units. According to the perception of respondents, the most frequent form of drug use is khat chewing (on average, 70.1% in previous week, 99% CI 63.6%–76.5%), followed by smoking cannabis (10.7%, 99% CI 0%–30.4%), ingesting psychoactive tablets (8.5%, 99% CI 0%–24.4%), drinking alcohol (5.3%, 99% CI 0%–13.8%), inhaling solvents (1.8%, 99% CI 0%–5.1%), and eating hemp seeds (0.6%, 99% CI 0%–2.0%). Perceived use of khat differs little between northern and southern Somalia, but perceived use of other drugs reaches alarmingly high levels in some regions of the south, especially related to smoking cannabis and using psychoactive tablets.

Conclusions

Our data suggest that drug use has quantitatively and qualitatively changed over the course of conflicts in southern Somalia, as current patterns are in contrast to traditional use. Although future studies using random sampling methods need to confirm our results, we hypothesize that drug-related problems of armed staff and other vulnerable groups in southern Somalia has reached proportions formerly unknown to the country, especially as we believe that any biases in our data would lead to an underestimation of actual drug use. We recommend that future disarmament, demobilization, and reintegration (DDR) programs need to be prepared to deal with significant drug-related problems in Somalia.  相似文献   

15.
Genetic variation was examined by electrophoresis in 14 populations of Stellaria arenicola, an endemic of the Athabasca sand dunes in northern Saskatchewan, Canada, and seven populations of S. longipes, its progenitor. Three of the 5. longipes populations were sympatric with the endemic. Populations of the endemic were found to have fewer alleles per polymorphic locus (2.21 vs. 2.37), fewer polymorphic loci (29.9 vs. 33.8), and lower genetic diversity (0.087 vs. 0.107) than populations of the progenitor. Genetic identities for all pairs of populations were high (0.932 to 1.000). The endemic had one novel allele and shared ten alleles with progenitor populations from the sand dunes that were not found in other populations of S. longipes. Populations of both species were found to partition most of their genetic variation within populations. An investigation of the multilocus outcrossing rates revealed that S. arenicola had higher rates of selling and biparental inbreeding than S. longipes. This study suggests that partial genetic isolation through a shift in the breeding system, in addition to previously reported strong directional selection, has been important in the sympatric evolution of the endemic S. arenicola. The close genetic relationship between populations of S. arenicola and S. longipes found on the Athabasca sand dunes supports the suggestion that the endemic evolved while sympatric to the gene pool of the progenitor species that is found presently in the region.  相似文献   

16.

Background  

Q fever, a worldwide zoonotic disease caused by Coxiella burnetii, is endemic in northern Spain where it has been reported as responsible for large series of human pneumonia cases and domestic ruminants' reproductive disorders. To investigate pathogen exposure among domestic ruminants in semi-extensive grazing systems in northern Spain, a serosurvey was carried out in 1,379 sheep (42 flocks), 626 beef cattle (46 herds) and 115 goats (11 herds). Serum antibodies were analysed by ELISA and positive samples were retested by Complement Fixation test (CFT) to detect recent infections.  相似文献   

17.
Ten endemic Chinese bird genera are currently recognized: Nipponia, Tetraophasis, Chrysolophus, Crossoptilon, Ithaginis, Pseudopodoces, Rhopophilus, Kozlowia, Urocynchramus and Latoucheornis. Of these genera, Nipponia, Ithaginis, Pseudopodoces, Rhopophilus, Kozlowia, Urocynchramus and Latoucheornis are monotypic, while Tetraophasis, Chrysolophus and Crossoptilon are polytypic. In this paper, we first set up a database of the geographic distribution and suitable habitat requirements for each species of these endemic genera. Secondly we produced a modified habitat-based prediction of their distribution using GIS (ArcView 3.1) software overlap analysis. We then explored the spatial–temporal distribution patterns of different genera. By comparing the richness of the endemic genera in distributed areas, we identified centers of endemic avian biodiversity. These are: the northern and eastern Hengduanshan Mountains, and the Qinling, Dabashan and Minshan Mountain regions. Finally, we identified conservation hotspots with a higher priority based on these centers. These results may provide a valuable tool for identifying and conserving areas with high endemic biodiversity and methods for researching the biogeography of endemic genera, the evolutionary history of fauna and species differentiation.  相似文献   

18.
We describe and illustrate four new species, Peliosanthes choriandra, P. tatianae and Tupistra orlovii from central to northern Laos, and Rohdea filosa from northern Vietnam. These are all very local in distribution and endemic to the respective countries. We also report new localities and their ecological conditions for five other species of Peliosanthes (P. argenteostriata, P. hirsuta, P. irinae, P. micrantha and P. nivea) recently described from Laos and/or Vietnam. Furthermore, Peliosanthes nivea is recorded as new to the flora of Laos.  相似文献   

19.
王文采 《广西植物》2017,37(5):541-546
该文描述了荨麻科三新种:(1)自中国重庆市发现的荨麻科荨麻属一新种,城口荨麻。此种与异株荨麻有亲缘关系,区别特征为此种的茎被少数刺毛,叶片多为心形,雄、雌花序均不分枝,瘦果在中央稍凹陷。(2)自中国广西发现的荨麻科赤车属一新种,来宾赤车。此种与特产云南东南部的富宁赤车相近缘,与后者的区别在于本种茎的毛开展或向上弯曲,叶片长椭圆形,基部斜楔形,雌花具3~4枚花被片,其中1~2枚较大花被片在背面顶端具一长筒状突起。(3)自缅甸北部发现的荨麻科楼梯草属一新种,克钦楼梯草。此种在体态上与骤尖楼梯草甚为相似,与后者的区别在于本种的每一茎节具正常叶和一退化叶,托叶狭披针状条形和无脉,雌总苞苞片无角状突起,雌小苞片较大,呈楔状长圆形,雌花具一小花被片,以及雌蕊具一宽倒卵球形柱头。  相似文献   

20.
Parasenecio auriculata is a woodland perennial herb widely distributed in Northeastern Asia, constituted by a poorly understood polyploidy with a diploid (2n=2x=60) and a tetraploid (2n=4x=120). In this study, for a better understanding of the polyploidal evolution, cytogeography and morphological variation were analyzed in Japanese P. auriculata, including two varieties; var. bulbifera endemic to central Hokkaido and var. kamtschatica widely distributed in northern Honshu and Hokkaido. The occurrence of two polyploidal levels was reconfirmed. While var. bulbifera is predominantly tetraploid, var. kamtschatica is comprised of diploid and tetraploid. Morphological variation among 22 quantitative characteristics is continuous and not distinctive among cytotypes or varieties, but plant size tended to be larger in the order, diploid of var. kamtschatica, var. bulbifera, and tetraploid of var. kamtschatica. The cytotype distribution showed a conspicuous geographical pattern. Besides var. bulbifera endemic to the central Hokkaido, the diploid of var. kamtschatica is mainly found in Southern Hokkaido, and the tetraploid has a disjunct distribution in eastern and northern Hokkaido and northern Honshu. Such a geographical pattern is possibly attributable to the differentiation of climatic preference among cytotypes and varieties, and may have been established in association with the climatic cline along the Japanese archipelago.  相似文献   

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