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1.
棕囊藻属的分类现状   总被引:10,自引:2,他引:8  
陈丽芬  章群  许忠能  刘宁宁  胡韧 《生态科学》2003,22(1):93-94,85
棕囊藻属藻类生活史复杂、地理差异显著、游动单细胞个体微小,至今尚无明确的分类标准。在目前已报道的9个种中,Sournia(1988)认为只有两个种比较可靠,即形成胶群体的P.pouchetii(sensu lato)(包括P.globosa)和不形成胶群体的P.scrobiculata;一些学者将P.puchetii(sensu lato)进一步细分成P.pouchetii(sensu stricto)、P.globosa,P.antarctica等3种,为方便起见,多数学者将形成胶群体的棕囊藻定名为P.pouchetii,或写成未定种的形式Phaeocystis sp.棕囊藻属分类的混乱制约了相关研究的深入,解决棕囊藻分类混乱问题有赖于新的技术和方法的使用。  相似文献   

2.
杉科、柏科是松柏类裸子植物中的重要类群,其系统分类研究一直是裸子植物的研究热点之一.但是杉科与柏科之间及其内部各属之间的系统发生关系却一直存在争议.一般认为杉科、柏科单独成科.近年来的分子系统学及分支系统学研究结果证实:除了金松属以外,杉科和柏科为一单系群,应合并为一个科Cupres-saceae sensu lato(广义柏科),其主要分支类群的系统发生关系也已经基本确立,而金松属则单独成立金松科.  相似文献   

3.
Giemsa C-banding was applied to the chromosome complements of six diploid species belonging to six genera in Chrysanthemum sensu lato (Anthemideae) distributed in Egypt.Four types of C-banding distribu...  相似文献   

4.
Based primarily on internal anatomy,the genus Agama(sensu lato)of Agamidae was subdivided into six genera:Agama,Laudakia,Trapelus,Pseudotrapelus,Brachysaura,and Xenagama[1,2].  相似文献   

5.
I<正>NTRODUCTION Changbaishan Nature Reserve is one of the most important forest reserves in China and it is very rich in wood-rotting fungi (Dai, 1997, 2000, 2003; Dai et al., 2003). Nearly 100 species of the Corticiaceae sensu lato  相似文献   

6.
新小竹属Neomicrocalamus为耿伯介先生于1983年发表,1986年他本人又将该属并入总序竹属Racemobambos中。但新小竹属具有假小穗及假花序而不同于总序竹属而仍宜保留为独立的属,前者应纳入(竹剌)竹族Bambuseae中,后者应纳入节柱竹族(广义的)Arthrostylidieae(sensu lato)。  相似文献   

7.
正Lyme disease is an emerging tick-borne disease in the U.S.,Europe,and Asia including China,and has become the most common vector-borne disease in both Europe and North America.Infection is caused by the spirochetal pathogen Borrelia burgdorferi sensu lato,transmitted via tick bites.The clinical manifestations of Lyme disease range from fever and skin lesions(erythema migrans)to multisystem disorders such as arthritis,carditis,and neuroborreliosis  相似文献   

8.
蜡样芽胞杆菌族(Bacillus cereus sensu lato)包括几个具有密切系统发育关系的芽胞杆菌物种,产生的毒素种类繁多,备受人们关注。质粒在菌株中的水平转移,会改变其表型、致病性和毒力,同时也带来分类的问题。通过综述几种蜡样芽胞杆菌毒素的结构特性、作用机制及其危害或生物应用,从质粒水平转移的角度介绍蜡样芽胞杆菌族成员错综复杂的关系。  相似文献   

9.
狭义多年异担子菌Heterobasidion annosum (Fr.) Bref. sensu stricto是广义多年异担子菌H. annosum sensu lato复合种之一,该病原菌引起的根腐病和根干基腐朽病在欧洲、北美针叶林造成严重损失。按照国际植物保护公约的有害生物风险分析原则(ISPM No.11),从地理分布、定殖可能性、扩散可能性、经济重要性和管理难度等方面对该病菌进行了定性分析,同时按照有害生物危险性评价指标体系及赋值标准,获得该病菌风险R值。结果显示:狭义多年异担子菌风险评估R值为2.38,属于高度危险林业有害生物,传入我国的风险较大、危害大,目前尚未列入我国禁止进境检疫性有害生物名录中。因此,建议将该病原菌尽快列入名录,以加强口岸检疫,严防其传入我国。  相似文献   

10.
黄美华 《动物学研究》1980,1(2):275-276
竹叶青Trimeresurus stejnegeri Schmidt卵胎生,烙铁头Trimeresurus mucrosquamatus(Cantor)卵生,有关这方面的具体资料尚缺。我们先后获得两条竹叶青母蛇产仔和一条烙铁头产卵,今列表简报如下:  相似文献   

11.
郭鹏 《四川动物》2005,24(3):428-431
2004年以来,广义竹叶青蛇的系统学研究取得了较大的进展。本文对这近一年来的最新进展进行概括和报道。  相似文献   

12.
广义烙铁头属三种烙铁头的核型及分类地位初步探讨   总被引:2,自引:0,他引:2  
报道3种烙铁头蛇的核型。其中,烙铁头2n=36=16M(14V+2SV/V)+20m,ZW型性决定,Z为V型,W为SI/SV型,Z明显大于W;菜花烙铁头2居群2n=36=16M(14V+2SI)+20m,ZW型性决定,Z为V型,W为SI型,Z明显大于W;云南竹叶青2n=36=16M(12V/SV+2SV/SI+2SI)+2m,无异型性染本,对3种的核型及烙铁头属已知核型进行了比较分析,并对云南竹叶  相似文献   

13.
亚洲蝮亚科蛇属间系统发生支序分析 (蛇亚目:蝰科)   总被引:1,自引:0,他引:1  
郭鹏  张服基 《生命科学研究》2000,4(3):262-266,280
在大量比较形态研究的基础上,选择了5个特征方面28个性状,以支序分析方法探讨了分布于亚洲蝮亚科蛇5属14种的系统发生关系,结果表明:该亚科蛇类可以划分为3个不同的类群,第一个类群包括尖吻蝮属、瘤鼻蝮属、红口腹属,它们具有较多的祖征,代表了该科中原始一类,基中红口蝮可能是最原始的一属;亚洲蝮属单独形成一个类群;第三个类群为原广义的烙铁头蛇属,包括竹叶青蛇属、原矛蝮属、烙铁头蛇属、黑绿烙铁头蛇属、莽山  相似文献   

14.
The Trimeresurus group is an important radiation of over 40 Asian pit viper species. Once considered congeneric, four genera are generally currently recognized (Trimeresurus sensu stricto, Ovophis, Protobothrops, and Tropidolaemus) but relationships within and between these are still unclear. This study, based on mitochondrial cytochrome b sequences, is the first to include a large number of species (21) and demonstrates that the current taxonomy does not adequately represent either the relationships or the genetic diversity present in the complex. Although many deeper nodes are not strongly supported, the following novel conclusions are all well supported: (1) the paraphyly of Trimeresurus sensu stricto, (2) the presence of several divergent clades within Trimeresurus sensu stricto, (3) the paraphyly of some widespread, medically significant, species, (4) the nonmonophyly of Ovophis, and (5) the monophyly of Protobothrops. Mapping of morphological characters onto the mitochondrial tree further supports the four groups proposed for Trimeresurus sensu stricto.  相似文献   

15.
LUQUE, T. & VALDÉS, B., 1984. Karyological studies on Spanish Boraginaceae: Lithospenum L. sensu lato . All of the Spanish taxa of Lithospermum L. sensu lato (Lithospermum sensu stricto, Neatostema, Buglossoides and Lithodora ), with the exception of Buglossoides gartonii (Bentham) I. M. Johnston, have been studied karyologically. The karyological characters allow the separation of three groups which do not correspond exactly with the morphological limits of the four genera actually recognized for Spain within Lithospermum sensu lato .
Se estudian cariológicamente los taxones españoles de Lithospermum L. sensu lato (Lithospennum sensu stricto, Neatostema, Buglossoides y Lithodora ), salvo Buglossoides gastonii (Bentham) I. M. Johnston. Por los caracteres cariológicos se pueden separar tres grupos cuyos límites no coinciden exactamente con los de los cuatro géneros actualrnente reconocidos para España dentro de Lithospcnum sensu lato .  相似文献   

16.
Relationships among the morphologically diverse members of Saxifragaceae sensu lato were inferred using 130 18S rDNA sequences. Phylogenetic analyses were conducted using representatives of all 17 subfamilies of Saxifragaceae sensu lato, as well as numerous additional taxa traditionally assigned to subclasses Magnoliidae, Caryophyllidae, Hamamelidae, Dilleniidae, Rosidae, and Asteridae. This analysis indicates that Saxifragaceae should be narrowly defined (Saxifragaceae sensu stricto) to consist of ~30 herbaceous genera. Furthermore, Saxifragaceae s. s. are part of a well-supported clade (referred to herein as Saxifragales) that also comprises lteoideae, Pterostemonoideae, Ribesioideae, Penthoroideae, and Tetracarpaeoideae, all traditional subfamilies of Saxifragaceae sensu lato, as well as Crassulaceae and Haloragaceae (both of subclass Rosidae). Paeoniaceae (Dilleniideae), and Hamamelidaceae, Cercidiphyllaceae, and Daphniphyllaceae (all of Hamamelidae). The remaining subfamilies of Saxifragaceae sensu lato fall outside this clade. Francoa (Francooideae) and Bauera (Baueroideae) are allied, respectively, with the rosid families Greyiaceae and Cunoniaceae. Brexia (Brexioideae), Parnassia (Parnassioideae), and Lepuropetolon (Lepuropetaloideae) appear in a clade with Celastraceae. Representatives of Phyllonomoideae, Eremosynoideae, Hydrangeoideae, Escallonioideae, Montinioideae, and Vahlioideae are related to taxa belonging to an expanded asterid clade (Asteridae sensu lato). The relationships suggested by analysis of 18S rDNA sequences are highly concordant with those suggested by analysis of rbcL sequences. Furthermore, these relationships are also supported in large part by other lines of evidence, including embryology. serology, and iridoid chemistry.  相似文献   

17.
Tu MC  Wang HY  Tsai MP  Toda M  Lee WJ  Zhang FJ  Ota H 《Zoological science》2000,17(8):1147-1157
Based on sequence variation in 806 bp of the mitochondrial 12S rRNA gene, phylogenetic relationships were inferred for 14 species of Trimeresurus (sensu lato) including all East Asian members. Samples analyzed also included representatives of all assemblages of species that are frequently treated as separate genera except for T. mangshanensis, a type species of the recently described monotypic genus Ermia. Results support some previous accounts chiefly from morphological studies, such as distinct divergence of T. wagleri from the remainder, and monophyly of T. mucrosquamatus, T. flavoviridis, T. jerdonii, T. elegans and T. tokarensis. On the other hand, our results negated a putative close affinity of T. monticola and T. okinavensis, and indicated the sister relationship of the latter with T. gracilis. Phylogenetic relationships revealed in this study suggested that the genus Trimeresurus dispersed into the Ryukyu region at least three times, and that T. flavoviridis and T. tokarensis from the central Ryukyus constitute a relict clade.  相似文献   

18.
More than a decade after a study on the transmission cycle of Borrelia burgdorferi sensu lato in the Siebengebirge, a nature reserve near Bonn, Germany, questing nymphal and adult Ixodes ricinus ticks were collected again in three selected areas of the same low mountain range and examined for infection with B. burgdorferi sensu lato. Between May and October 2001, a total of 1,754 ticks were collected by blanket dragging; 374 ticks were analyzed for B. burgdorferi sensu lato by both an immunofluorescence assay (IFA) and at least two different PCR tests, whereas 171 ticks were analyzed by PCR only. By combining all assays, an average of 14% of the ticks tested positive for B. burgdorferi sensu lato, 5.5, 15.8, and 21.8% in the three collection areas. Of the nymphs and adults examined, 12.9 and 21.1%, respectively, were found to be spirochete infected. A lower total infection prevalence was obtained by IFA (14.4%) than by a nested PCR approach (16.5%), but both were higher than that obtained by a simple PCR approach (11.9%). Compared with data collected over a decade ago, the mean infection prevalence of B. burgdorferi sensu lato in the ticks was significantly higher for all three biotopes, whereas a similar pattern of habitat-specific infection prevalence was observed. Genotyping of B. burgdorferi sensu lato revealed high relative prevalences of B. valaisiana (identified in 43.1% of infected ticks) and B. garinii (32.3%), whereas B. afzelii (12.3%) and B. burgdorferi sensu stricto (1.5%) were relatively rare. We conclude that B. burgdorferi sensu lato infection has increased in this region over the last 15 years due to presently unknown changes in ecological conditions, perhaps related to climate change or wildlife management.  相似文献   

19.
To evaluate the prevalence rate of tick-borne bacterial pathogens, unfed adult Ixodes ricinus ticks were collected from vegetation in 2001, 2003, and 2004 at 18 localities throughout Serbia. A total of 287 ticks were examined by PCR technique for the presence of Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum, and Francisella tularensis. The highest prevalence rate was that for B. burgdorferi sensu lato (42.5%), followed by A. phagocytophilum (13.9%) and F. tularensis (3.8%). The presence of five B. burgdorferi sensu lato genospecies, namely, B. burgdorferi sensu stricto, B. afzelii, B. garinii, B. lusitaniae, and B. valaisiana was identified by restriction fragment length polymorphism (RFLP) analysis. The most frequent B. burgdorferi sensu lato genospecies was B. lusitaniae, followed by B. burgdorferi sensu stricto. Co-infection by B. burgdorferi sensu stricto and B. lusitaniae was frequently observed. Co-infection by B. burgdorferi sensu lato and A. phagocytophilum and co-infection by B. burgdorferi sensu lato and F. tularensis appeared in 24 ticks. Sequencing of p44/msp2 paralogs of Serbian A. phagocytophilum showed that they were unique and distinct from those of A. phagocytophilum in US and UK. This is the first report of B. garinii, B. lusitaniae, B. valaisiana, as well as A. phagocytophilum and F. tularensis infected ticks in Serbia. These findings indicate a public health threat in Serbia of tick-borne diseases caused by B. burgdorferi sensu lato, A. phagocytophilum and F. tularensis.  相似文献   

20.
Lyme borreliosis (LB) group spirochetes, collectively known as Borrelia burgdorferi sensu lato, are distributed worldwide. Wild rodents are acknowledged as the most important reservoir hosts. Ixodes scapularis is the primary vector of B. burgdorferi sensu lato in the eastern United States, and in the southeastern United States, the larvae and nymphs mostly parasitize certain species of lizards. The primary aim of the present study was to determine whether wild lizards in the southeastern United States are naturally infected with Lyme borreliae. Blood samples obtained from lizards in Florida and South Carolina were tested for the presence of LB spirochetes primarily by using B. burgdorferi sensu lato-specific PCR assays that amplify portions of the flagellin (flaB), outer surface protein A (ospA), and 66-kDa protein (p66) genes. Attempts to isolate spirochetes from a small number of PCR-positive lizards failed. However, PCR amplification and sequence analysis of partial flaB, ospA, and p66 gene fragments confirmed numerous strains of B. burgdorferi sensu lato, including Borrelia andersonii, Borrelia bissettii, and B. burgdorferi sensu stricto, in blood from lizards from both states. B. burgdorferi sensu lato DNA was identified in 86 of 160 (54%) lizards representing nine species and six genera. The high infection prevalence and broad distribution of infection among different lizard species at different sites and at different times of the year suggest that LB spirochetes are established in lizards in the southeastern United States.  相似文献   

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