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1.
Genus Eurydoxa Filipjev in China is reviewed and noted for the first time. Based on the present study, two species are recognized, including rhodopa Diakonoff and advena Filipjev. All available information for the species is reviewed and provided.  相似文献   
2.
Taxa of conservation interest are frequently identified using morphological or ecological characters. These characters are assumed to represent evolutionary importance, population structure and/or phylogenetic relationships in such organisms. We tested this assumption using two species complexes of the moth genus Hemileuca (Saturniidae). Both have populations threatened by habitat loss and need conservation protection. Legislation protects one taxon with apparent ecological differences. We sequenced 624 base pairs of mtDNA from the COI gene for geographically distant populations of the Hemileuca maia species complex and the H. electra species complex. Resultant phylogenies contradict prior assumptions about relationships in both species complexes. The legislatively protected Bog Buckmoth is paraphyletic with widespread H. maia, and its use of a novel hostplant seems to be a local adaptation. Divergent morphology and hostplant use among H. electra subspecies are associated with modest genetic divergence (0.48%). However, a group of unrecognized populations that are morphologically similar and geographically close to H. electra electra have mtDNA that is divergent by an average of 4.1%. There is disagreement regarding prioritization of ecological divergence over neutral genetic distance in conservation. We place ecological variation in a phylogenetic context and recommend that exploration of genetic relationships be undertaken when populations are threatened. Adaptive ecological variation should be evaluated in a phylogenetic context to understand its conservation importance. This study illustrates the importance both of phylogenetic context and the use of independent characters in assessing biodiversity for conservation prioritization.  相似文献   
3.
Some anatomical, adult shell and larval features of Unto coffer Krauss are described and compared to those reported in previous accounts of this and other species. The findings necessitate the removal of U. caffer from the nominal genus Cafferia Simpson, for which it is the type species, and its return to the genus Unio Pbilipsson, in the Unionidae: Unioninae. Cafferia consequently becomes a junior subjective synonym of Unto.

Unio caffer is characterized in part by zigzag beak sculpture, dimorphic septal spacing between the marsupial, outer (comparatively dense) and the non-marsupial, inner (more distant) demibranchs and also within the marsupial demibranchs, the presence of perforated marsupial septa and imperforate non-marsupial septa, the occurrence of hermaphrodites in some but apparently not all populations, production of subtriangular glochidia with a hook at the ventral margin of each valve, short-term incubation of larvae in the marsupial demibranchs, and by its disjunct occurrence in the southern Ethiopian region (other Unio occurring only in the Palearctic).

These adult shell and anatomical features relate this species to those of several nominal genera in the Oriental region, although the latter are distinguished from it by the production of subovate, hookless glochidia.  相似文献   
4.
韩辉林  李成德 《林业研究》2007,18(2):144-146
本文报道了分布于黑龙江省塔和地区的2个中国夜蛾科新记录种:北方纬夜蛾Atrachea japonica (Leech, 1889) 和暗绿丫金翅夜蛾Autographa macrogamma (Eversmann, 1842),同时首次将以新种记述于韩国和台湾省的中文夜蛾Neustrotia rectilineata Ueda, 1987在大陆予以报道.对标本材料的外部形态特征、生殖器图片和世界性分布予以记述.所用标本材料收藏在东北林业大学林学院昆虫实验室.  相似文献   
5.
An Olethreutine speciesCymolomia hartigiana (Saxesen, 1840), attacking toAbies nephrolepis Max., is reported for the first time from Daxing'anling, Heilongjiang, China. The morphological characteristics are briefly re-described with illustrations. Also its damage and biology are noted. Foundation item: This study was carried out under the financial support by KOSEF (Korea Science & Engineering Foundation) with the program of “Korea and China Young Scientist Exchange Program” (2002–2003). Biography: *BYUN Bong-Kya (1963-), male, Ph.D., Researcher in Korea National Arboretum, Korea. Responsible editor: Chai Ruihai  相似文献   
6.
Modern molecular technologies are having a substantial impact in many fundamental and applied areas of parasitology. In particular, polymerase chain reaction (PCR)-coupled approaches have found broad applicability because their sensitivity permits the enzymatic amplification of gene fragments from minute quantities of nucleic acids from tiny amounts of parasite material. Also, high-resolution electrophoretic and genomic methods are finding increased utility. This paper briefly discusses some developments and applications of DNA methods to parasites and highlights their usefulness or potential for those of veterinary importance. Selected examples of applications with implications in fundamental (systematics, population genetics, epidemiology and ecology) and applied (diagnosis, prevention and control) areas are presented. The focus is mainly on tools for the accurate identification of parasitic nematodes and protozoa of socio-economic importance, the diagnosis of infections and the detection of genetic variability using PCR-coupled mutation scanning technology.  相似文献   
7.
落叶松属系统学研究概况   总被引:4,自引:0,他引:4  
落叶松属系统学、分类学的研究在俄罗斯已有很长历史,基本可以划分为三个阶段,即18 ̄19世纪的落叶松属系统学研究的初始阶段。20世纪初期落叶松属研究的发展阶段及现代落叶松属系统学的深入研究阶段。随着研究的深入,使落叶松系统学及这研究日趋完善,演化路线越见清晰,种及种下分类越趋合理。但由于研究者利用的研究手段不同。研究范围不同。所以还存在有一些有争议的地方,除此之外,这些争论也是由该种的生物学特性所决  相似文献   
8.
Venturiales     
Members of Venturiales (Dothideomycetes) are widely distributed, and comprise saprobes, as well as plant, human and animal pathogens. In spite of their economic importance, the general lack of cultures and DNA data has resulted in taxa being poorly resolved. In the present study five loci, ITS, LSU rDNA, tef1, tub2 and rpb2 are used for analysing 115 venturialean taxa representing 30 genera in three families in the current classification of Venturiales. Based on the multigene phylogenetic analysis, morphological and ecological characteristics, one new family, Cylindrosympodiaceae, and eight new genera are described, namely Bellamyces, Fagicola, Fraxinicola, Fuscohilum, Neofusicladium, Parafusicladium, Pinaceicola and Sterila. In addition, 12 species are described as new to science, and 41 new combinations are proposed. The taxonomic status of 153 species have been re-evaluated with 20 species excluded from Venturiales. Based on this revision of Venturiales, morphological characteristics such as conidial arrangement (solitary or in chains) or conidiogenesis (blastic-solitary, sympodial or annellidic), proved to be significant at generic level. Venturia as currently defined represents a generic complex. Furthermore, plant pathogens appear more terminal in phylogenetic analyses within Venturiaceae and Sympoventuriaceae, suggesting that the ancestral state of Venturiales is most likely saprobic.  相似文献   
9.
蝉总科昆虫以其雄性能发出响亮而多样的鸣声著称。长期以来,不同学者相继对其发音机制及发音器官形态结构在系统学、生态学等方面进行了广泛研究,积累了丰富的资料。在此基础上,对蝉总科昆虫的发音机制、鸣声类型及其行为功能方面的研究进展进行综述,并从蝉总科高级阶元分类系统的建立、鸣声的进化与物种形成、鸣声在种级单元分类及分子系统发育研究中的应用等角度,探讨发音器官形态结构及其鸣声在蝉总科昆虫系统学、生态学研究中的重要性;阐述鸣声比对及DNA条形码技术在蝉总科近缘物种和疑难物种区分、隐存物种发现、生物多样性评估及基因树冲突解析等方面的重要意义。针对当前研究中存在的一些问题,强调今后在解析蝉总科系统发育关系和演化历史研究中综合采用形态特征、鸣声特征和分子数据的必要性,以及蝉总科昆虫的声学、行为学研究结果在害虫声学诱集防治及仿生学领域可能具有的潜在价值。  相似文献   
10.
气孔器微形态及其在本科植物分类中的意义气孔器最常见于叶片上,在叶片发育过程中,叶分生组织产生原表皮细胞与其它部分相隔离,原表皮细胞又转变成次生分生组织,再由这些分生组织形成保卫细胞和副卫细胞而组成气孔器。从起源而言,它是植物登陆后在适应环境的长期演化...  相似文献   
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