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11.
珲春自然保护区生态评价   总被引:3,自引:0,他引:3  
从多样性,自然特征代表性,稀有性,自然性,生态脆弱性,面积适宜性,人类威胁等7个方面对珲春自然保护区进行了生态评价,最终得出评价分值:74.7.珲春自然保护区表现出了在野生生物和自然生态系统保护方面的优先地位,它与现有国家级同类保护区相近,符合《自然保护区类型与级别划分原则》中国国家标准中有关国家级自然保护区的规定,应升级为国家级自然保护区,并予以重点保护.  相似文献   
12.
以(S)-4-苄基-2-噻唑硫酮为手性助剂,与丁烯酰氯进行N-酰化反应,所得酰化产物与溴代正丁烷的铜试剂进行不对称迈克尔加成反应,在NaBH4作用下解脱得到(R)-3-甲基庚醇,再经氰化、水解等反应,合成出椰树犀牛甲虫聚集信息素,其化学总产率为39.45%,光学异构体纯度达93%e.e.以上。  相似文献   
13.
《Journal of Natural History》2012,46(7-8):485-496
Previously known species of the genus Ceratanisus Gemminger, 1870 are studied, based on a comparison of specimens. This study is a first attempt to scrutinize the composition of this poorly known genus, as a preliminary approach to the tribe Ceratanisini Gebien, 1937. As a result of this study three previously described taxa are recognized as valid species and three new species from Turkey, Ceratanisus selimi sp. nov., Ceratanisus labriquei sp. nov. and Ceratanisus andiberti sp. nov., are described. A key for the separation of the genera of Ceratanisini is presented, including the new species described herein.  相似文献   
14.
Males in six of seven species of Phyllophaga perform apparent courtship behaviour during copulation. As predicted by the hypothesis that such copulatory courtship is under sexual selection by female choice, behavioural details differ between species. The modified male abdominal sternites, which rub against the female's pygidium during copulation and whose morphology also differs between species, and the flattened, setose tarsi of males of one species probably function as contact courtship devices during copulatory courtship. Observations of events inside copulating beetles were made through the semi-transparent abdominal sternites of females and male genitalia in three species. They revealed cryptic genitalic thrusting behaviour of male genitalia within the female which occurred even when there was little or no external movement of the male genitalia. Dissections of pairs frozen in copula demonstrated that males transfer large quantities of material to females during copulation that is not physically related to sperm transfer. The type of material varied between species. In at least two species most of the transfer apparently occurred after sperm transfer. The possibility that some male genitalic structures function as holdfasts and/or stimulatory devices was suggested by their positions relative to female structures, and/or their movements within the female. Portions of male genitalia with strong bristles tended to lie against setose or more heavily sclerotized portions of the female reproductive duct. Some portions of female genitalia which vary between species seem ill-designed to exclude the genitalia of cross-specific males. The female reproductive tract is partially everted during copulation in one species.  相似文献   
15.
    
The seed beetles, Acanthoscelides quadridentatus and Acanthoscelides winderi are here recorded for the first time feeding on seeds of Mimosa setosa var. paludosa in the Brazilian Cerrado. Our main aims were to describe the temporal distribution, seed damage, and notes on the natural history of these two species on their host plant. We hypothesised that: (a) healthy seeds from infested fruits would have worse germination rate than healthy seeds from noninfested fruits, and (b) females of seed beetles would lay more eggs on large fruits. We made field observations and an experimental field study with the presence of seed beetles versus their exclusion on plants. Results revealed that seed beetles are synchronised with fruiting, with a temporal partitioning in occurrence. Attacked seeds did not germinate, whereas healthy seeds from infested fruits had worse germination rate than healthy seeds from noninfested fruits. Females of seed beetles laid more eggs on large fruits. These results suggest that seed beetles avoid competition through a temporal partitioning curcial for their coexistence, and select large fruits to oviposit as these fruits probably provide more food resource for their offspring. Furthermore, plants might perceive seed beetles’ damage and then reduce resource allocation on infested fruits.  相似文献   
16.
    
Cassidinae Gyllenhaal? is the second largest subfamily of Chrysomelidae (Coleoptera), which presents characteristic morphology, biology and behaviour. The current study describes the life cycle of Paraselenis(Spaetiechoma) dichroa (Germar), ?determining biological and behavioural aspects as well as the action of natural enemies on populations, when the species has maternal care. The study was conducted between February and April 2015 in the National Forest of Passa Quatro, municipality of Passa Quatro, Minas Gerais state, Brazil. Daily observations were made (morning and afternoon) to evaluate the offspring of females on Ipomoea sp. and Merremia macrocalyx (O’Donell?) (Convolvulaceae), as well as the actions of natural enemies on the young. The eggs are deposited on the midrib and abaxial surface of leaves (n = 25). Egg clusters are pedunculated, arranged in groups and devoid of any cover. On average, each female produced 27.3 ± 5.6 (n = 16) eggs, with a mean incubation period of 12.7 ± 2.9 days (n = 10 females with their young). The larvae remained grouped in the leaves throughout development, except when they fed. They retained faeces and exuviae as a stacked faecal structure on their mobile urogomphi (caudal process) like a faecal shield. The mean number of larvae per female was 12.7 ± 10.1 (n = 19) and the larval period lasted 24.9 ± 4.5 days (n = 12). Pupation occurred on the stem of the plant (n = 16). On average there were 8.1 ± 8.5 individuals for pupae progeny (n = 14). The mean duration of the pupal stage was 10.4 ± 3.3 days (n = 5). Overall, 3% of adults emerged (n = 13 individuals), with a total cycle time of 41.3 ± 8.4 days (n = 6). Adults are sexually dimorphic in the elytral shape. Females remain with the offspring throughout development. The natural enemies of immatures were Emersonella pubipennis Hansson? (Hymenoptera: Eulophidae), Tachinidae (Diptera) and Stiretrus decastigmus (Herrich-Schaeffer?) (Heteroptera: Pentatomidae), Conura sp. Spinola? (Hymenoptera: Chalcididae) and Brachymeria sp. Westwood? (Hymenoptera: Chalcididae). The information presented here on the natural history of P. dichroa are important as they may serve as a starting point to understand evolutionary questions and multispecies interactions.  相似文献   
17.
18.
《Journal of Natural History》2012,46(25-26):1585-1636
An updated species list of four beetle families is given for Turkey. A total of 35 genera and 167 species and subspecies are known to occur in Turkey. Ten species and two subspecies are from the family Gyrinidae, 16 species are from the family Haliplidae, three species are from the family Noteridae and 129 species and seven subspecies are from the family Dytiscidae.  相似文献   
19.
《Journal of Natural History》2012,46(25-26):1505-1584

The present paper gives a review of the species so far assigned to the genus Gynaecoserica Brenske, 1896 Brenske, E. 1896. Insectes du Bengale. Melolonthidae. Ann Soc Entomol Belg., 40: 150164.  [Google Scholar]. Thirty-two new species are described: Gynaecoserica alma sp. nov., G. amara sp. nov., G. arunachalensis sp. nov., G. barclayi sp. nov., G. bicolorata sp. nov., G. bocaki sp. nov., G. bomdilana sp. nov., G. compacta sp. nov., G. densipunctata sp. nov., G. digna sp. nov., G. dirangensis sp. nov., G. exilis sp. nov., G. gisionensis sp. nov., G. hirsuta sp. nov., G. ignobilis sp. nov., G. jelineki sp. nov., G. keithi sp. nov., G. lobiceps sp. nov., G. lohitensis sp. nov., G. lomsakensis sp. nov., G. lubosi sp. nov., G. luteata sp. nov., G. maekasana sp. nov., G. maymyoensis sp. nov., G. nahangensis sp. nov., G. namtamaiensis sp. nov., G. obliqua sp. nov., G. rostrata sp. nov., G. schima sp. nov., G. seinghkuensis sp. nov., G. vogleri sp. nov. and G. ziyardamensis sp. nov. The genitalia of the new species are figured and the distribution of the species is illustrated. Two new combinations are established: G. marginipes (Brenske, 1896 Brenske, E. 1896. Insectes du Bengale. Melolonthidae. Ann Soc Entomol Belg., 40: 150164.  [Google Scholar]) comb. nov. and G. felina (Arrow, 1946 Arrow, GJ. 1946. Entomological results from the Swedish expedition 1934 to Burma and British India. Coleoptera, Melolonthidae. Ark Zool., 38A(9): 133.  [Google Scholar]) comb. nov.; the lectotype of the latter is designated. In addition to the species diagnoses a key to all so far known Gynaecoserica species is provided.  相似文献   
20.
《Journal of Natural History》2012,46(17-18):1095-1111
A scarab beetle genus, Madecorphnus Paulian, endemic to Madagascar, is revised. Nine new species are described: M. brunneus sp. nov., M. dentatus sp. nov., M. montreuili sp. nov., M. niger sp. nov., M. pauliani sp. nov., M. perinetensis sp. nov., M. peyrierasi sp. nov., M. punctatus sp. nov., M. simplex sp. nov. Diagnosis of the genus is clarified. Distribution map and a diagnostic key to all species are presented.  相似文献   
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