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1.
中国淡水钩虾一新种(甲壳纲:端足目:钩虾科)   总被引:1,自引:0,他引:1  
记述了采自四川九寨沟自然保护区的淡水钩虾1新种,四川钩虾Gammarus sichuanensisi sp.nov.新种的形态特征和与近似种的区别在文中均有详细的论述,同时附有详细的特征图,模式标本保存于中国科学院动物研究所。  相似文献   

2.
记述了采自湖北省宣恩县长潭河的淡水沟虾1新种,溪水钩虾Gammarus riparius sp.nov.。该种隶属于G.balcanicus-group,其鉴别特征为:第2触角鞭节无鞋形感觉器,4-5腹节背部无刺或刚毛。文中对新种的形态特征和与近似种的区别均有详细的论述,并附有详细的特征图。新种模式标本保存在中国科学院动物研究所。  相似文献   

3.
记述了采自北京的端足目钩虾科钩虾属一新种,琥珀钩虾Gammarus electrus sp.nov。文中详细描述了其形态特征和与近似种的比较,同时附有特征图。模式标本采自北京植物园樱桃沟等地,保存于中国科学院动物研究所。  相似文献   

4.
中国无眼钩虾一新种记述(甲壳纲,端足目,钩虾科)   总被引:2,自引:1,他引:1  
记述了中国钩虾属1新种,盲钩虾Gammarus aocu-lus sp.nov.,文中详细描述了其形态特征和与近似种的区别,并附有特征图。模式标本保存于中国科学院动物研究所。  相似文献   

5.
记述了分布在新疆乌拉泊水库、米泉铁厂沟和乌鲁木齐市郊的淡水钩虾1新种,华美钩虾Gammarus decorosus sp.nov.。文中详细描述了其形态特征和与近似种的比较,同时附有特征图。模式标本保存于中国科学院动物研究所。  相似文献   

6.
记述了采自安徽华阳洞的假褐钩虾属1新种,洞穴假褐钩虾Pseudocrangonyx cavernarius sp.nov.。该种区别于同属其它种为:第1小颚内叶具4根刚毛,第2尾肢外肢为内肢的66%,第3尾肢肢节为柄节的3.25倍,尾节末端微裂。文中附有详细的特征图。模式标本保存于中国科学院动物研究所。  相似文献   

7.
记述采自中国四川省洞穴钩虾属1新种,奇异钩虾Gammarus praecipuus sp.nov.(图1~56).新种与钩虾属其它物种的区别在于:眼睛缺失;第1小颚外叶具有31个齿,明显多于其它钩虾属物种的11个齿;第1尾肢内、外肢无侧刺或毛;第3尾肢内肢为外肢长的一半.正模♂;副模:2♂♂,2♀♀,四川省江油市新春乡藏王寨无名洞,2010年5月12日,林玉成采.模式标本保存在中国科学院动物研究所.词源:新种种名源自该种具有特殊的洞穴特征,如第1小颚外叶具多个齿以及第1尾肢内、外肢无侧刺或毛;形容词.  相似文献   

8.
记述了采自安徽巢湖忠庙的端足目畸钩虾科大螯属一新种,巢湖大螯蜚Grandidierella chaohuensis sp.nov.文中详细描述了其形态特征和与近似种的区别,同时附有特征图。模式标本保存于中国科学院动物研究所。  相似文献   

9.
报道了采自云南的端足目异钩虾科沼泽宽肢钩虾1新属1新种,Eurypodogammarus helobius gen.nov.et sp.nov..宽肢钩虾属区别于其它属在躯体粗壮,每个基节鳃只有1个附鳃.文中详细描述了新属新种的个体特征及其与近似属种的比较,同时附有特征图.研究标本保存于中国科学院动物研究所.  相似文献   

10.
强壮藻钩虾的繁殖及胚胎发育的形态学观察   总被引:1,自引:0,他引:1  
强壮藻钩虾隶属于节肢动物门甲壳纲端足目钩虾亚目的一种小型水生生物,在20世纪80年代初由任先秋首次记录并进行形态学描述,主要分布在中国黄海、渤海、东海、日本和北太平洋海岸。强壮藻钩虾主要生活在有机物丰富的海水中并常栖息于大型水草中,可全年在野  相似文献   

11.
12.
The anomuran crabs are among the best known crustacean groups from the Pacific coast. However, this group is poorly known from the Caribbean coast of Costa Rica. In this compilation based on the literature and the collection at the Zoology Museum, Biology School, University of Costa Rica, we report the presence of 114 species of the Infraorder Anomura for Costa Rica, 20 species from the Caribbean, 96 species from the Pacific (two are present on both coasts). Twenty-nine species are new reports for Costa Rica, 15 from the Caribbean coast (74% of the total of species from that coast) and 14 from the Pacific (15% of the total from the Pacific). The range often species is extended to Costa Rica, siete from the Caribbean and three from the Pacific. Six species are reported for the first time from Cocos Island, where there are also four endemic species.  相似文献   

13.
By definition, a vitamin is a substance that must be obtained regularly from the diet. Vitamin A must be acquired from the diet, but unlike most vitamins, it can also be stored within the body in relatively high levels. For humans living in developed nations or animals living in present-day vivariums, stored vitamin A concentrations can become relatively high, reaching levels that can protect against the adverse effects of insufficient vitamin A dietary intake for six months, or even much longer. The ability to accumulate vitamin A stores lessens the need for routinely consuming vitamin A in the diet, and this provides a selective advantage to the organism. The molecular processes that underlie this selective advantage include efficient mechanisms to acquire vitamin A from the diet, efficient and overlapping mechanisms for the transport of vitamin A in the circulation, a specific mechanism allowing for vitamin A storage, and a mechanism for mobilizing vitamin A from these stores in response to tissue needs. These processes are considered in this review.  相似文献   

14.
15.
Webba da Silva M 《Biochemistry》2005,44(10):3754-3764
A template-based approach was used to design unprecedented architectural motifs into a known DNA framework. The structure formed by the sequence d(GCGGTTGGAT) in 0.1 M Na(+) solution has been determined using molecular dynamics simulations constrained by distance and dihedral restraints derived from NMR experiments. The molecular topology has been previously observed for the sequence d(GCGGTGGAT) (Webba da Silva, M. (2003) Biochemistry 42, 14356-65). Insertion of a single thymine into the double chain reversal formed by the segment GGTGG results in the unprecedented experimental demonstration of a T:(G:G:G:G):T hexad. The bi-stranded hexad results from the pairing alignment of two G(T-G) triads. Each triad results from recognition of the sheared edge of a guanine by the Watson-Crick edge of a thymine of the segment GGTTGG. The alignment is stabilized by base-stacking of the thymine to the sugar pucker of the preceding thymine. The latter is involved in formation of the T:A:A:T tetrad alignment by forming a hydrogen bond with the free amino proton of a Watson-Crick aligned A:A mispair. We have thus established that residues in double chain reversal loops linking juxtaposed tetrads of a quadruplex stem may facilitate formation of yet unknown hydrogen bond alignments. By employing a systematic approach analysis of sequence motifs appearing in double chain reversals, bridging tetrad layers should allow for the prediction of topologies and architectural motifs appearing in biologically relevant genomic regions.  相似文献   

16.
Abstract Semiocladius Sublette and Wirth, described from adult midges from south-western Pacific Ocean shores, has the Australian Camptocladius crassipennis Skuse as its type. Immature stages previously known only from Semiocladius kuscheli Sublette and Wirth from sub-Antarctic New Zealand were associated tentatively, by co-occurrence. For the first time, the immature stages for the Australian species are associated definitively by rearing. Larvae rear to a pupa identical to a speculatively associated exuviae of Semiocladius from Lord Howe Island. Adults conform to the described S. crassipennis . Larval Semiocladius are distinctive and previous diagnoses are confirmed. In contrast, the putatively associated pupa of S. kuscheli is indistinguishable from that of the marine intertidal Thalassosmittia Strenke and Remmert, whereas the newly associated S. crassipennis pupa is distinct. The pupa of S. kuscheli may have been misassociated. Semiocladius live in the mesohaline of the salinity gradient of the Clyde River estuary, south-east Australia and the genus appears to be a distinctive western Pacific saline/mesohaline taxon.  相似文献   

17.
Adult whiteflies, Bemisia tabaci (Gennadius), collected from the field were screened for viral pathogens using a cell line from the silverleaf whitefly, B. tabaci, B biotype (syn. B. argentifolii). Homogenates from the field-collected whiteflies were applied to cell cultures and checked for cytopathic effects (CPE). Cells were observed to develop cytoplasmic inclusions and to have a change in morphology. Cells displaying CPE were observed using a transmission electron microscope and found to be infected with a virus. The virus particles had an icosahedral shape and an approximate size of 120-130 nm. The virus was observed in defined areas of the cytoplasm adjacent to the cell nucleus. Analysis using polymerase chain reaction, Southern blot hybridization, and DNA sequencing confirmed that the virus discovered infecting the whitefly cell cultures was an iridovirus. Sequence analysis showed that the amplimer (893 bp) had a 95% homology to the invertebrate iridescent virus type 6 major capsid protein gene. Discovery of new viruses of whiteflies may provide renewed interest in using pathogens in the development of innovative management strategies. This is the first report of an iridescent virus isolated from whiteflies, B. tabaci, collected from the field.  相似文献   

18.
Phylogenetics of Cancer crabs (Crustacea: Decapoda: Brachyura).   总被引:4,自引:0,他引:4  
We used morphological, mitochondrial DNA sequence, paleontological, and biogeographical information to examine the evolutionary history of crabs of the genus Cancer. Phylogenies inferred from adult morphology and DNA sequence of the cytochrome oxidase I (COI) gene were each well resolved and well supported, but differed substantially in topology. Four lines of evidence suggested that the COI data set accurately reflected Cancer phylogeny: (1) in the phylogeny inferred from morphological data, each Atlantic species was sister taxon to an ecologically similar Pacific species, suggesting convergence in morphology; (2) a single trans-Arctic dispersal event, as indicated by the phylogeny inferred from COI, is more parsimonious than two such dispersal events, as inferred from morphology; (3) test and application of a maximum likelihood molecular clock to the COI data yielded estimates of origin and speciation times that fit well with the fossil record; and (4) the tree inferred from the combined COI and morphology data was closely similar to the trees inferred from COI, although notably less well supported by the bootstrap. The phylogeny inferred from maximum likelihood analysis of COI suggested that Cancer originated in the North Pacific in the early Miocene, that the Atlantic species arose from a North Pacific ancestor, and that Cancer crabs invaded the Atlantic from the North Pacific 6-12 mya. This inferred invasion time is notably prior to most estimates of the date of submergence of the Bering Strait and the trans-Arctic interchange, but it agrees with fossil evidence placing at least one Cancer species in the Atlantic about 8 mya.  相似文献   

19.
20.
Hartini S  Takaku G 《Zoological science》2003,20(10):1261-1272
Twelve mite species of the genus Macrocheles (Acari: Macrochelidae) were collected from the body surface of dung beetles in Java, Indonesia. Of these, three species, i.e., Macrocheles jabarensis, M. jonggolensis, and M. sukabumiensis, were described as new to science. Female of M. dispar was redescribed. Two species, i.e., M. baliensis and M. sukaramiensis, were recorded from Java for the first time. The occurrence of five species previously recorded from Java, i.e., M. hallidayi, M. kraepelini, M. limue, M. oigru, and M. merdarius, were reconfirmed. Taxonomic status of M. sp. aff. glaber was not settled in the present study, because we could not obtain the male and immatures which are indispensable for exact identification. In total 15 species of the genus Macrocheles, including 3 species already recorded but not collected in this research (M. crispa, M. krantzi, and M. subbadius), are known from Java up to date.  相似文献   

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