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1.
The phylogenetic relationships of elasmobranchs, especially sharks, are unclear. All previously made research and hypotheses indicate that there are still unsolved relationships within and between the class Chondrichthyes. To find out the relationship and sister group of this genus, the ribosomal ITS1-2 regions sequence has been chosen to differentiate the genus Carcharhinus from the blue shark (genus Prionace) and from some other genus species as an outgroup. The results show that the blue shark is a member of the genus Carcharhinus, suggesting that maybe the blue shark belongs also to the genus Carcharhinus instead of Prionace, or that there is a misclassification, Prionace being not a separate genus.  相似文献   

2.
The genus Dysoxylum is a large genus comprising of about a dozen species, distributed in India. This is the genus which is rich in compounds like terpenoids and alkaloids. The isolated compounds from the genus were reported to have interesting biological activities. This review contains the chemical structures, along with their biological activities reported in the literature.  相似文献   

3.
对瓢蜡蝉科Issidae扁足瓢蜡蝉属Neodurium Fennah进行了订正。记述中国扁足瓢蜡蝉属4种,包括1新种,钩扁足瓢蜡蝉Neodurium hamatum sp.nov.,提供了形态及雌雄性外生殖器等特征图。制作了本属分布于中国的7个种的分种检索表。钩扁足瓢蜡蝉,新种N.hamatum sp.nov.(图1~24)新种与Neodurium postfasciatum Fennah相近似,其区别主要在于:前翅有爪缝,但端部较模糊,肛节端部不弯曲,阳茎具1对钩状突起。新种模式标本保存在西北农林科技大学昆虫博物馆。正模♂,云南勐仑,2009-07-23,张磊采。副模1♀,云南勐仑,2009-07-12,张磊采。词源:新种种名据其阳茎具钩状突起而定名。  相似文献   

4.
Cyclorhiza, a new genus based upon Ligusticum waltonii Wolff, is here proposed. From the ample materials now in our herbarium, we found that the genus differs from the species of Ligusticum. As the result of our study, the systematic position of this new genus should be considered as a member of the tribe Smyrnieae Koch. Chuanminshen, another new monotypic genus, is here also proposed. It was often considered as not different from Changium Wolff, but it is a cleary deliminated natural genus being quite remote from Changium Wolff. This new genus is quite reasonably to be placed in the tribePeucedaneae.  相似文献   

5.
A re-examination of Lepidostrobus Brongniart   总被引:1,自引:0,他引:1  
Lepidostrobus is a genus that was established by Brongniart for Palaeozoic lycopod cones. Since then the genus has been used for a variety of cones that have similar characters. There is now compelling evidence that the genus represents a heterogeneous group of monosporangiate and bisporangiate cone species and that it should be divided. Lepidostrobus is rediagnosed as a genus of microsporangiate cones. Ftemingites Carruthers is rediagnosed as a genus of those bisporangiate cones formerly included in Lepidostrobus.  相似文献   

6.
中国筇竹属植物志资料   总被引:4,自引:0,他引:4  
筇竹属是近年来新建立的一个属。本属原发表时仅有3种,标本採自四川、云南、贵州及湖北西部。以后又陆续发表了4种。作者在编写中国植物志筇竹属的过程中,对本属又做了初步整理,其中包括一新种及一新变型也在此一并发表。本文引证的标本均藏于本院标本室(代号SWFC)。  相似文献   

7.
鮊属和红鮊属模式种的订正   总被引:1,自引:1,他引:1  
鲤科鮊亚科中的鱼类是东亚特有的一个类群,在我国分布甚广,种类较多,为常见的经济鱼类.有关鱼类的分类已有不少学者作过研究,本文主要讨论Cutter alburnus Basilewsky和Cutter erythropterus Basilewsky两个种的性状经订正后而涉及鮊属(Cutter)和红舶属(Erythroculter),与模式种的性状相一致的问题,并根据现有材料将鮊鱼类进行分类整理.    相似文献   

8.
Abstract. The South African genus Pameridea and its two species are redescribed. The tribe Pamerideini, founded for this genus only, is removed from synonymy with Mirini (subfamily Mirinae) and transferred to Dicyphini (subfamily Bryocorinae), falling as a synonym of the subtribe Dicyphina. The bugs live only on intensely viscid small shrubs of the genus Roridula. This plant genus is the only member of its family but the bug genus is closely related to two widespread tropical dicyphine genera.  相似文献   

9.
DNA sequences of the mitochondrial nd6 gene and the non-repetitive part of the pseudo-control region (PsiCR) were isolated from 101 individuals to analyze the phylogenetic relationships among all buzzards of the genus Buteo and other buteonine genera. Comparisons of the two marker sequences indicate that the PsiCR evolved two times faster than the nd6 gene. The PsiCR proved to be an efficient, neutral genetic marker sequence for phylogenetic analyses at the intrageneric level, especially suitable for analyses based on old tissues, where only short fragments can be obtained. The molecular data set implies a neotropical origin of the genus Buteo. Monophyly of the genus Buteo as currently defined is contradicted due to the positions of Asturina nitida, Geranoaetus melanoleucus, Buteo magnirostris, and Buteo leucorrhous. These findings suggest several taxonomic consequences. A. nitida and G. melanoleucus should be included into the genus Buteo. Moreover, B. leucorrhous should be transferred into the genus Percnohierax (which clusters with Parabuteo), and B. magnirostris into the genus Rupornis. According to this classification of the genus Buteo, the basal lineage of the genus is formed by a clade containing Buteo polyosoma, Buteo poecilochrous, and Buteo melanoleucus. The "woodland buteos" form a paraphyletic assemblage with B. magnirostris as a clearly separated lineage basal to the genus Buteo.  相似文献   

10.
11.
The bacterial genus Serpula Stanton et al. 1991 is illegitimate due to the existence of a fungal genus Serpula Pers. ex S. F. Gray. Consequently, a new genus designation, Serpulina, is proposed for this spirochete genus. Serpula hyodysenteriae, the type species, and Serpula innocens Stanton et al. 1991, therefore, become Serpulina hyodysenteriae comb. nov. and Serpulina innocens comb. nov.  相似文献   

12.
The genus Dichocarpum was established by W. T. Wang and Hsiao in 1964, who divided the genus into 2 sections: Sect. Dichocarpum including 10 species distributed on the mainland of E. Asia, and Sect. Hutchinsonia including 9 species native to Japan. M. Tamura and L. A. Lauener made a revision of the genus in 1968, who divided the genus into 4 sections, three for the species of the mainland of E. Asia, including 3 series and 10 species, and the other for the species of Japan, including 2 subsections, 3 series and 9 species. In the present paper, the genus is divided into 2 sections and 6 series, including 15 species and 3 varieties, and a putative phylogeny of the genus is proposed. The genus may be close to the genus Asteropyrum, and these two genera are rather specialized in Thalictroides (Ranunculaceae), because they have three very similar characters: the petal with a long claw, the stephanocolpate pollen and the chromosome morphology. The genus has 2n=24, 35(36?), which indicates that its basic number is X=6, and the species on the mainland of E. Asia (Sect. Dichocarpum) may well be paleotetraploids, whereas those in Japan (sect. Hutchinsonia) are paleohexaploids. Most of the advanced species are distributed in Japan and the most primitive ones in China and the Himalayas, the distribution pattern seggests that the Japanese members of this genus might have immigrated from China in the Tertiary, and differentiated and evolved there. The putative phylogeny of the genus is shown in Fig. 2 (at series level)  相似文献   

13.
Genomic information has already been applied to prokaryotic species definition and classification. However, the contribution of the genome sequence to prokaryotic genus delimitation has been less studied. To gain insights into genus definition for the prokaryotes, we attempted to reveal the genus-level genomic differences in the current prokaryotic classification system and to delineate the boundary of a genus on the basis of genomic information. The average nucleotide sequence identity between two genomes can be used for prokaryotic species delineation, but it is not suitable for genus demarcation. We used the percentage of conserved proteins (POCP) between two strains to estimate their evolutionary and phenotypic distance. A comprehensive genomic survey indicated that the POCP can serve as a robust genomic index for establishing the genus boundary for prokaryotic groups. Basically, two species belonging to the same genus would share at least half of their proteins. In a specific lineage, the genus and family/order ranks showed slight or no overlap in terms of POCP values. A prokaryotic genus can be defined as a group of species with all pairwise POCP values higher than 50%. Integration of whole-genome data into the current taxonomy system can provide comprehensive information for prokaryotic genus definition and delimitation.  相似文献   

14.
Leymus is a genus in the Triticeae tribe, Poaceae. The taxa of this genus are allopolyploid species which possess the Ns and Xm genomes. According to cytological, cytogenetic and molecular genetic analyses, some species of Hystrix and Elymus ought to be transferred to this genus. A world revision of the genus Leymus is needed. In this paper we summarize experimental results, provide a key to sections, species and varieties, and list all the taxa we recognize in Leymus with their synonyms. This synopsis is a new taxonomic system to be used for the revision of Leymus.  相似文献   

15.
海洋放线菌盐孢菌属研究进展   总被引:1,自引:0,他引:1  
1991年,Jensen等从热带及亚热带海洋样品中分离获得了放线菌目专性海洋放线菌类群MAR1。根据形态学特征、生理生化特征及16S rRNA基因分析,提议该类群为新属——盐孢菌属(Salinospora)。2005年,盐孢菌属被正式报道,并将Salinospora更正为Salinispora。盐孢菌属是放线菌目第一个被报道的专性海洋微生物属,可以产生丰富的活性次级代谢产物,使盐孢菌属成为海洋微生物研究的热点。短短几年内,相继报道了许多研究成果。本文从盐孢菌属的建立过程、属及所含种的分类特征、生理生态学研究、次级代谢产物和分子生物学研究等方面对盐孢菌属的研究进展进行综述。  相似文献   

16.
中国杭子梢属植物的研究   总被引:2,自引:0,他引:2  
傅沛云 《植物研究》1987,7(4):11-55
本文叙述了杭子梢属(gen.Campylotropis)植物的研究历史,说明在中国一共记录过59种杭子梢属植物,经过著者的研究整理,确定并提出了14种新的异名名称,经过详细考订,本属植物在中国已确知为29种、6变种、6变型。其中包括经发现和研究整理的新种4、新变种3、新变型3、新组合变种2、新组合变型3。此外尚有2个存疑种有待今后采集调查解决。本文历述了关于本属是否应该并入胡枝子属(gen.Lespedeza)这一问题所存在的长期争议之后,详细论述了本属与胡枝子属在特征上的异同诸点、进行了比较和分析,据此,明确地肯定本属与胡枝子属亲缘关系极为相近,但特征的分化已经必须确认本属应是与胡枝子属有明确区别的独立的属。此外,从特征分析中也可得出本属应是由胡枝子属大胡枝子组(sect.Macrolespedeza)演化发展而来的。本文在讨论了属内主要特征的演化趋势与种群关系之后,论述了本属在世界主要分布地区的种数和分布概况,同时将此与胡枝子属大胡枝子组的分布概况作了比较和分析,明确地认定我国机子梢属植物的大部分种类是本国西南地区发生的(中国有20个特有种),我国的西南地区是本属植物的分布中心,也是本属植物从较原始特征开始分化的一个特征分化多样化中心,并且此地区正是胡枝子属大胡枝子组与本属多数种类包括较原始种类分布相交叉的地区,因而我国的西南地区有可能即是本属植物的起源中心,并且这一起源应是与胡枝子属大胡枝子组植物分布到中国西南地区以后的分化发展想联系的。  相似文献   

17.
A morphological and osteological study on a large number of specimens, together with zoogeographical data, indicate that the genus Bathyclarias , previously synonymized with the genus Dinotopterus , is a valid genus. It is rehabilitated in this paper. Bathyclarias is endemic to Lake Malawi, while Dinotopterus is confined to Lake Tanganyika.  相似文献   

18.
19.
根据叶表皮特征试论国产三齿稃亚族的属间关系   总被引:4,自引:3,他引:1  
根据植物叶片表皮结构,尤其下表皮特征,对国产三齿稃亚族6个属(包括1个引进属)进行了属间关系的分析。结果表明:国产三齿稃亚族中固沙草属最原始,草沙蚕属最高级,双稃草属、千金子属、三齿稃属和隐子草属演化居于其间;隐子草属可能直接起源于固沙草属,并在自身基础上派生了较为高级的三齿稃属;双稃草属与千金子属渊源关系直接,前者可能通过后者问接起生于固沙草属;草沙蚕属具有别于它属的性状级次,可能是起源于固沙草属、独树1支的顶级类群。这一结果不仅修正了前人演化理论的差误,而且为今后探讨该亚族的地理起源、散布路线提供了资料。  相似文献   

20.
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