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1.
Although monkey B virus (herpesvirus simiae; BV) is common in all macaque species, fatal human infections appear to be associated with exposure to rhesus macaques (Macaca mulatta), suggesting that BV isolates from rhesus monkeys may be more lethal to nonmacaques than are BV strains indigenous to other macaque species. To determine if significant differences that would support this supposition exist among BV isolates, we compared multiple BV strains isolated from rhesus, cynomolgus, pigtail, and Japanese macaques. Antigenic analyses indicated that while the isolates were very closely related to one another, there are some antigenic determinants that are specific to BV isolates from different macaque species. Restriction enzyme digest patterns of viral DNA revealed marked similarities between rhesus and Japanese macaque isolates, while pigtail and cynomolgus macaque isolates had distinctive cleavage patterns. To further compare genetic diversity among BV isolates, DNA sequences from two regions of the viral genome containing genes that are conserved (UL27 and US6) and variable (US4 and US5) among primate alphaherpesviruses, as well as from two noncoding intergenic regions, were determined. From these sequence data and a phylogenetic analysis of them it was evident that while all isolates were closely related strains of BV, there were three distinct genotypes. The three BV genotypes were directly related to the macaque species of origin and were composed of (i) isolates from rhesus and Japanese macaques, (ii) cynomolgus monkey isolates, and (iii) isolates from pigtail macaques. This study demonstrates the existence of different BV genotypes which are related to the macaque host species and thus provides a molecular basis for the possible existence of BV isolates which vary in their levels of pathogenicity for nonmacaque species.  相似文献   

2.
The size of some Trichogramma spp. adults and especially the ovipositor length depends on the species, but is also related to the host species and to the number of parasitoids per host. The length is greater in T. evanescens than in T. pretiosum itself greater than in T. exiguum, but the width is similar in the three species. For T. evanescens, the size obtained in Mamestra brassicae host when three or four insects emerged is similar to that obtained in Ephestia kuehniella host when singly parasitized. The size of the ovipositor is important because it may influence the possibility of in vitro egg laying in artificial host eggs. A shorter or a narrower ovipositor could cause difficulties in egg-laying into artificial host eggs composed of a membrane of unsuitable thickness.  相似文献   

3.

Background

Host association patterns in Ectoedemia (Lepidoptera: Nepticulidae) are also encountered in other insect groups with intimate plant relationships, including a high degree of monophagy, a preference for ecologically dominant plant families (e.g. Fagaceae, Rosaceae, Salicaceae, and Betulaceae) and a tendency for related insect species to feed on related host plant species. The evolutionary processes underlying these patterns are only partly understood, we therefore assessed the role of allopatry and host plant family shifts in speciation within Ectoedemia.

Methodology

Six nuclear and mitochondrial DNA markers with a total aligned length of 3692 base pairs were used to infer phylogenetic relationships among 92 species belonging to the subgenus Ectoedemia of the genus Ectoedemia, representing a thorough taxon sampling with a global coverage. The results support monophyletic species groups that are congruent with published findings based on morphology. We used the obtained phylogeny to explore host plant family association and geographical distribution to investigate if host shifts and allopatry have been instrumental in the speciation of these leafmining insects.

Significance

We found that, even though most species within species groups commonly feed on plants from one family, shifts to a distantly related host family have occasionally occurred throughout the phylogeny and such shifts are most commonly observed towards Betulaceae. The largest radiations have occurred within species groups that feed on Fagaceae, Rosaceae, and Salicaceae. Most species are restricted to one of the seven global biogeographic regions, but within species groups representatives are commonly found in different biogeographic regions. Although we find general patterns with regard to host use and biogeography, there are differences between clades that suggest that different drivers of speciation, and perhaps drivers that we did not examine, have shaped diversity patterns in different clades.  相似文献   

4.
《Journal of Asia》2007,10(1):17-19
We report three species of the family Noctuidae, Catocala hyperconnexa Sugi, Xylomoia fusei Sugi and Hydraecia ultima Holst, for the first time from China, with illustrations of adult and genitalia.  相似文献   

5.
《Journal of Asia》2007,10(2):113-115
Two species of the family Incurvariidae, Vespina nielseni Kozlov and Paraclemensia monospina Nielsen, are reported for the first time from Korea. The morphological characteristics of adults and the female genitalia of the two species are redescribed briefly, with illustrations.  相似文献   

6.
记述采自海南省太阳隼属1新种:华氏太阳隼Heliocyphahuai,sp.nov.和采自贵州省印度隼属1新种:赤水印度隼Indocyphachishuiensis,sp.nov.。模式标本保存于浙江自然博物馆昆虫标本室。  相似文献   

7.
地黄属种间亲缘关系研究   总被引:9,自引:1,他引:9  
闫坤  赵楠  李宏庆 《西北植物学报》2007,27(6):1112-1120
对地黄属6个物种进行了形态解剖学观察、染色体计数、核核糖体内转录间隔区(ITS)序列分析.结果表明,茎的高度、幼叶形态、花萼和花冠形态及颜色、种子千粒重和大小、外种皮网壁厚度、外种皮内侧网纹直径等均是该属内分类的可靠依据.高地黄与裂叶地黄在外部形态及解剖结构的各个方面均极为近似,地黄与茄叶地黄间也存在较大的相似性.茄叶地黄、高地黄、湖北地黄、天目地黄的染色体数目,分别为n=28、14、14、14,确认地黄和茄叶地黄为属内四倍体物种,其余种均为二倍体.ITS测序分析显示,地黄属为单系起源,天目地黄与湖北地黄、高地黄与裂叶地黄、地黄与茄叶地黄构成属内3个分支,与形态学及细胞学研究结果一致.研究认为,天目地黄与湖北地黄有较近的亲缘关系;高地黄和裂叶地黄应为同一物种;地黄与茄叶地黄是属内进化水平最高的类群.  相似文献   

8.
This study addressed the problem of local patterns of host specificity among Ancyrocephalinae (Monogenoidea) on bass and sunfish species, when the hosts occur in different species combinations in separate ponds. One hundred fifty-three fish of the Centrarchidae, from 4 study sites in Nebraska, were collected. Host species included bluegill (Lepomis macrochirus), green sunfish (L. cyanellus), largemouth bass (Micropterus salmoides), black crappie (Pomoxis nigromaculatus), white crappie (P. annularis), and rock bass (Ambloplites rupestris). These fish occurred in different species combinations, depending on the pond sampled. Results indicated that several centrarchid species could inhabit the same pond and yet support distinct monogene communities. Clavunculus bursatus, Onchocleidus helicis, O. principalis, and Syncleithrum fusiformis were found only on largemouth bass, regardless of what other centrarchids were present in a particular pond. Haplocleidus dispar occurred on green sunfish, bluegill, largemouth bass, and black crappie, and H. furcatus occurred on both bluegill and largemouth bass. Onchocleidus cyanellus and O. ferox were found on both bluegill and green sunfish. Rock bass were present in only 1 of the 4 ponds, but were not infected with any monogenes, even though co-occurring centrarchids were often heavily infected. Largemouth bass had the most diverse ancyrocephaline communities. The degree of parasite host specificity among these monogenes was inversely related to the diversity of host species present in a particular pond. In general, the parasites were more host specific than might be inferred from the literature; parasite species did not necessarily colonize supposedly receptive host species even when the latter were present, and host relatedness was the major factor in determining whether host species shared a common parasite species.  相似文献   

9.
The gastrointestinal tract contains a vast community of microbes that to this day remain largely unculturable, making studies in this area challenging. With the newly affordable advanced sequencing technology, important breakthroughs in this exciting field are now possible. However, standardized methods of sample collection, handling, and DNA extraction have yet to be determined. To help address this, we investigated the use of 5 common DNA extraction methods on fecal samples from 5 different species. Our data show that the method of DNA extraction impacts DNA concentration and purity, successful NGS amplification, and influences microbial communities seen in NGS output dependent on the species of fecal sample and the DNA extraction method used. These data highlight the importance of careful consideration of DNA extraction method used when designing and interpreting data from cross species studies.  相似文献   

10.
Climate warming and major land-use changes have profoundly affected the Mongolian landscape in the past several decades. Previous studies have recognized the impacts of a warmer, more arid climate and Mongolia’s 1991 transition from a command to a market economy on terrestrial ecosystems, including impaired sustainability of subsistence herding and threats to wild animals. In this study, we examined the combined effects of changing climate and herding practices on lake eutrophication in Western Mongolia. We sampled 65 lakes for modern nutrients and found the majority of lakes were eutrophic to hyper-eutrophic. Sediment cores were taken from five of the lakes to compare current lake status to paleolimnologial measures of lake eutrophication over the past 100–2000 years, including changes in diatom assemblages, diatom-inferred total phosphorus, biogenic silica, organic matter, and sediment accumulation rates. Variance partitioning analysis showed that recent shifts in diatom assemblages were related to changes in both climate and herding practices. The results presented here demonstrate a need for further study and long-term monitoring of water quality in Mongolia to understand the complicated interactions of climate and land use on aquatic resources and to preserve water quality in this remote and ecologically important region.  相似文献   

11.
We investigated spatially variable selection in Ambystoma tigrinum virus (ATV) which causes frequent and geographically widespread epizootics of the tiger salamander, Ambystoma tigrinum. To test for evidence of selection, we sequenced several coding and noncoding regions from virus strains isolated from epizootics throughout western North America. Three of the sequenced regions contained homologues for genes putatively involved in host immune evasion and virulence: eIF‐2α, caspase activation and recruitment domain (CARD) and β‐OH‐steroid oxidoreductase. Selection analysis showed evidence of very strong purifying selection on eIF‐2α, purifying selection within certain viral clades on CARD and positive selection on β‐OH‐steroid oxidoreductase within certain clades. Analysis using multidivtime and Tajima’s relative rate tests indicate accelerated rates of evolution within clades associated with anthropogenic movement. These clades also demonstrate greater spatial variability in selection, suggesting a lack of local adaptation (i.e. locally adapted populations should exhibit little to no selection because of absent or reduced variation in fitness once a fitness optimum is reached). Increased transfer of non‐native viral strains to naïve salamander populations, in conjunction with local maladaptation as a result of local selection pressures, may explain the spread and emergence of ATV epizootics in A. tigrinum in western North America.  相似文献   

12.
Abstract Total seed yield per plant in one season was differentiated neither between Epimedium diphyllum and the E. grandiflorum complex ( E. grandiflorum and E. sempervirens ), nor between these two groups and one of their hybrid derived species, E. trifoliatobinatum . Total ovules per plant and seed-set rate per capsule ( SR ) did not vary greatly between these species, and seed weight ( SW ) was almost the same between them. The number of flowers per inflorescence ( F ) was also constant. However, the remaining reproductive component characters, ovule number per ovary ( O ) and inflorescence number per plant ( I ), were differentiated between the three taxa. These two characters were negatively correlated and a trade-off relationship occurred under the constant total seed yield (= O × F × I × SR × SW ). Ovule number per ovary was highly correlated with spur length of the flower. During the course of the hybrid speciation of E. trifoliatobinatum , selection pressure by pollinators on intermediate spur length seems to have favored plants with an intermediate ovule number. On the other hand, this selection pressure counteracted the increase of the inflorescence number under the trade-off. The resultant seed yield of E. trifoliatobinatum did not differ from that of the parental species, but the pattern of ovule allocation to ovaries (capsules) was altered.  相似文献   

13.
记述了天牛科Cerambycidae花天牛亚科Lepturinae驼花天牛属Pidonia1新记录种——雅玛驼花天牛Pidonia (Pidonia) yamato Hayashi et Mizuno,标本保存在西南大学昆虫博物馆。  相似文献   

14.
在整理长白山生物调查所得标本时,发现夜蛾科3中国新记录种:长白拟毛眼夜蛾Mniotype bathensis(Lutzau,1900),尘梦尼夜蛾Orthosia coniortota(Filipjev,1927)和真鲁夜蛾Xestia sincera(Herrich-Schaffer,1851),并对此3种的外部形态和雄性外生殖器特征做了简要描述。同时修正了毛眼夜蛾属(Blepharita Hampson,1907)和拟毛眼夜蛾属(Mniotype Franclemont,1941)在国内混淆的关系。  相似文献   

15.
Pytho depressus (Linnaeus) of the family Pythidae is recorded in Korea for the first time. Pythidae is also introduced newly in Korea as one family of the superfamily Tenebrionoidea. We provide photos of habitus and illustrations of aedeagus for identification.  相似文献   

16.
We present a phylogenetic investigation of the Northern Clade, the major monophyletic clade within the freshwater fish family Cobitidae, one of the most prominent families of freshwater fishes found in Asian and European waters. Phylogenetic reconstructions based on the cytochrome b and RAG-1 genes show the genera Microcobitis, Sabanejewia, Koreocobitis and Kichulchoia as monophyletic groups. These reconstructions also show a Cobitis sensu lato and a Misgurnus sensu lato group. The Cobitis sensu lato group includes all species of Cobitis, Iksookimia, Niwaella and Kichulchoia, while the Misgurnus sensu lato group includes Misgurnus, Paramisgurnus and Koreocobitis. Although the monophyly of both the Cobitis sensu lato and Misgurnus sensu lato groups is supported, relationships within the groups are incongruent with current generic definitions. The absence of monophyly of most genera included in the Cobitis sensu lato group (Cobitis, Iksookimia and Niwaella) or their low genetic differentiation (Kichuchoia) supports their consideration as synonyms of Cobitis. Molecular phylogenies indicate that the Asian species of Misgurnus experienced a mitochondrial introgression from a lineage of Cobitis. We also find two nuclear haplotypes in the same Cobitis species from the Adriatic area that, in the absence of morphological differentiation, may indicate molecular introgression. Most lineages within the Northern Clade consist of species found in East Asia. However, some lineages also contain species from Europe and Asia Minor. The phylogenetic relationships presented here are consistent with previous studies suggesting an East Asian origin of the Northern Clade. According to the current distributions and phylogenetic relationships of the Misgurnus sensu lato and Cobitis clade lineages, particularly of M. fossilis and C. melanoleuca, the range expansion of East Asian species into Europe was most likely via Siberia into Northern and Central Europe. Phylogenetic analyses also show that the Cobitis sensu lato group consists of two clear subgroups (I and II), each presenting geographical differences. Subgroup I is distributed exclusively in East Asian drainages with an Eastern European offshoot (C. melanoleuca), whereas Subgroup II includes species widespread throughout Europe (including the Mediterranean), Asia Minor, the Black Sea and the Caucasus, with some lineages related to species restricted to East Asia.  相似文献   

17.
Adult neurogenesis is a highly regulated, multi-stage process in which new neurons are generated from an activated neural stem cell via increasingly committed intermediate progenitor subtypes. Each of these subtypes expresses a set of specific molecular markers that, together with specific morphological criteria, can be used for their identification. Typically, immunofluorescent techniques are applied involving subtype-specific antibodies in combination with exo- or endogenous proliferation markers. We herein describe immunolabeling methods for the detection and quantification of all stages of adult hippocampal neurogenesis. These comprise the application of thymidine analogs, transcardial perfusion, tissue processing, heat-induced epitope retrieval, ABC immunohistochemistry, multiple indirect immunofluorescence, confocal microscopy and cell quantification. Furthermore we present a sequential multiple immunofluorescence protocol which circumvents problems usually arising from the need of using primary antibodies raised in the same host species. It allows an accurate identification of all hippocampal progenitor subtypes together with a proliferation marker within a single section. These techniques are a powerful tool to study the regulation of different progenitor subtypes in parallel, their involvement in brain pathologies and their role in specific brain functions.  相似文献   

18.
Sex allocation by the polyphagous solitary pupal parasitoid wasp Pimpla luctuosa Smith to a small host species, Galleria mellonella (L.), and a large host species, Mamestra brassicae L., was investigated to test whether female wasps responded to hosts of different sizes across different host species. In the experiments, both host species were presented to each test female wasp. Primary and secondary sex ratio experiments revealed that female wasps laid more female eggs in larger pupae of each host species, indicating that female wasps recognized size differences within host species. The wasp sex ratio (male ratio) from M. brassicae, however, was much higher than that expected on the basis of the sex ratio curve from different-sized G. mellonella. Larger hosts of each host species yielded larger wasps, indicating that the host size estimation by female wasps across different host species was incomplete or was not simple. These results suggested that P. luctuosa evaluated host size not only by physical measures such as dimension but also by other unknown measures. A possible explanation for the adaptiveness of different sex ratio responses by Pimpla luctuosa to different host species was discussed.  相似文献   

19.
A high degree of intraspecific variation, both genetic and in shell morphology, of the operculate land snail Cyclophorus fulguratus (Pfeiffer, 1854) suggests that its classification as a single species warrants reconsideration. We sequenced two nuclear (18S and 28S) and two mitochondrial (16S and COI) genes of 46 C. fulguratus specimens and used them to estimate the phylogeny and to determine the validity of species boundaries. Molecular phylogenetic analyses revealed the presence of three lineages corresponding to three geographically disjunctive populations of C. fulguratus in Thailand. Likelihood tests of topologies significantly supported the non-monophyly of the C. fulguratus–complex and Bayesian species delimitation analysis significantly supported the potential representation as distinct species of these three lineages. Discriminant function analysis based on geometric-morphometrics of shell shape allowed for significant distinction of these three candidate species, although they revealed a considerable degree of overlap of shell shape reflecting their crypsis morphologically. The diagnostic characters are provided by color pattern, pattern of protoconch and pattern of jaw. In conclusion, the results support that the C. fulguratus s.l., as currently recognized, consists of three distinct species in Thailand: C. fulguratus s.s., C. rangunensis and C. abditus sp.nov., which are described herein.  相似文献   

20.
记述中国盾蚧科2新种:拟额瘤并盾蚧Pinnaspis pseudotuberculatua sp.nov.和云南兜盾蚧Duplachionaspis yunnanensis sp.nov.。模式标本保存在西北农林科技大学昆虫博物馆。  相似文献   

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