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1.
昆虫的翅     
昆虫纲是动物界中最大的一纲,分两个亚纲,三十三个目,有100多万种。它占整个动物界种数的80%以上,是植物界种数的兰倍,而未经定名的尚有许多。昆虫不但种类多,种的个体数量大(如一个蜂群多达五万余只),而且分布广(除广阔的海洋外,几乎遍及全球)。昆虫能如此繁盛,是与它惊人的适应能力有关,其中一个重要原因,就是它们具有翅。这使昆虫在觅食、求偶、避敌和扩大分布等方面具有优越的竞争能力。昆虫的翅是无脊椎动物中特有的结构,这种结构也是昆虫在长期进化过程中形成  相似文献   

2.
珍稀濒危植物单性木兰传粉生态学研究   总被引:4,自引:0,他引:4       下载免费PDF全文
野外定位观测了单性木兰的花期物候、访花昆虫种类、访花频率、访花行为和同花期植物种类,并对其花粉散播距离和繁育系统进行了检测,旨在探讨制约单性木兰传粉过程的某些因素,为单性木兰的保护生物学提供科学依据。结果表明,单性木兰雄株和雌株在花期物候上存在差异,雌株在结实上存在明显的大小年现象。单性木兰以虫媒传粉为主,雄株访花昆虫30种,雌株访花昆虫仅14种,雌株和雄株共有的访花昆虫仅6种。单性木兰同花期植物共17种,其访花昆虫种类大部分与单性木兰的访花昆虫种类相同。蜂类和蝶类均非单性木兰的传粉者,其结实率低的原因不仅与访花昆虫种类少和访花频率少有关,更与其缺乏有效的传粉昆虫有关。  相似文献   

3.
昆虫种类数量的变化   总被引:4,自引:0,他引:4  
黄复生 《昆虫知识》1991,28(6):374-374
<正> 昆虫与人类生活的关系极为密切,人们的衣、食、住、行无不与之有关。所以昆虫数量之大、种类之多一直为人们所关注的问题,很早以前对于昆虫种类就有过种种猜测。50年代初期Simpson认为全世界生物有200万种。那时有人认为全世界昆虫种类有100万种,不过  相似文献   

4.
四川南充市春季麦田昆虫群落结构初步调查   总被引:1,自引:0,他引:1  
通过巴氏罐诱法及网捕法、目测法,对南充市4月份的麦田昆虫群落进行分层调查,结果显示地表昆虫5目14科30种,其中天敌昆虫1目2科5种;麦田中上层昆虫7目10科21种,其中天敌昆虫4目5科16种。调查表明南充市麦田昆虫种类较多,天敌昆虫种类丰富,不同种类天敌昆虫占据不同的生态位,各自发挥作用,应保护利用。  相似文献   

5.
中国夜蛾科昆虫区系初步研究(鳞翅目:双孔亚目)   总被引:5,自引:0,他引:5  
对我国分布记载较详细的1410种夜蛾科昆虫区系分析结果表明:1)在世界昆虫区系中,可分为17个分布型,以东洋界种类最多,占35.6%;古北界种类居第二,占33.0%;古北界和东洋界共有种类居第三,占23.0%。2)中国夜蛾科昆虫主要由古北界种类、东洋界种类、古北界和东洋界共有种类组成,占总数的91.7%;与澳洲界共有67种,占4.8%;与非洲界共有51种,占3.6%;与新北界共有23种,占1.6%  相似文献   

6.
我国热带地区是外来入侵物种发生与危害的重灾区,近年来外来有害昆虫入侵所引发的生物灾害及生态安全问题日趋严峻。在海南省、广东省、广西壮族自治区、云南省、福建省外来入侵昆虫的调查结果及文献资料的基础上,整理分析了中国热带地区外来入侵昆虫的种类构成、分布、原产地及首次发现地。据统计,2000-2014年我国热带地区的外来入侵昆虫种类共计23种,隶属于6目11科,数量最多的为半翅目(13种,56.52%),其中以粉蚧科和粉虱科居多;热带地区的外来入侵昆虫在不同地区之间的物种数量差异较大,其中海南省最多(19种,82.61%),其后依次为广东省(16种,69.57%)、云南省(14种,60.87%)、广西壮族自治区(12种,52.17%),而福建省最少(9种,占39.13%);在入侵我国热带地区的外来有害昆虫中,原产于亚洲、北美洲的种类最多均为6种,占26.09%,南美洲占21.74%,而从非洲、大洋洲、欧洲传入的分别占8.70%、4.35%、4.35%;外来入侵昆虫的首次发现地位于广东省的有9种,占39.13%,出现在海南省和云南省的各占30.43%、21.74%,出现在广西壮族自治区的为8.70%。阐明我国热带地区外来有害昆虫的种类特征及入侵现状,可为该地区外来入侵昆虫的监测与防控提供一定的依据。  相似文献   

7.
本文报道了广东省鹤山市南亚热带丘陵人工林昆虫群落的变化动态,结果表明,在该生态系统中2002年比1993年调查的昆虫种类增加3目、76科、781种。其中,蝗虫类增加6科18种、蜻蜓类增加2科23种、蝶类增加4科48种。这一结果说明经过9年的植被恢复,昆虫种类大量增加,昆虫群落结构趋于复杂化。  相似文献   

8.
贵南沙蜥分布在青海省贵南县的一片长×宽约为30 km×20 km的连续沙丘,该沙丘被周缘草地隔离,贵南沙蜥主要在沙地与草地接触带的沙地一侧活动。采用3条样线共150个陷阱研究贵南沙蜥在草地与沙地交界线两侧的活动洞穴空间分布特征与潜在的可利用性昆虫食物资源多样性,并分析洞穴空间分布特征与昆虫种类以及数量分布的关系。研究共捕获1236个昆虫个体,隶属于2纲10目26科42种,其中昆虫纲有7目21科37种978个,蛛形纲有3目5科5种258个;草地采集的昆虫有2纲9目22科37种570个,沙地有2纲9目21科33种666个。草地昆虫的Shannon-Wiener,Simpson多样性指数与均匀度指数均大于沙地,表明草地的昆虫食物资源较丰富且分布均匀。研究表明贵南沙蜥在沙地环境活动洞穴数量较多,且离交界线越近洞穴分布数量越多;草地生境活动洞穴空间分布与离交界线距离无相关性,相对沙地数量较少且空间上分布较均匀。草地样方捕获的昆虫种类和数量以及沙地样方捕获的昆虫数量都与离分界线的距离无关,但沙地上昆虫种类与离分界线的距离呈高度负相关。研究表明贵南沙蜥沙地活动洞穴空间分布与昆虫种类分布特征显著相关。  相似文献   

9.
虫害严重威胁着我国的粮食安全,迁飞昆虫中有许多是农业害虫,其远距离迁飞是导致虫害异地暴发的重要原因.昆虫雷达是观测昆虫迁飞最有效的工具,在迁飞昆虫的监测和预警中发挥着越来越重要的作用,但传统昆虫雷达不能准确获取昆虫的各项生物学参数,因此无法实现昆虫种类的精确识别.随着雷达技术的创新和发展,通过昆虫雷达获得较为准确的昆虫生物学参数成为可能,为基于昆虫雷达实现迁飞昆虫个体种类辨识提供了依据.本文综述了从雷达回波中提取多频和极化散射参量,然后基于不同的电磁散射反演昆虫生物学参数的方法,并对比分析了基于不同方法的昆虫体重、体长、体宽和振翅频率的反演精度.最后基于生物学参数,采用5种机器学习算法以高精度实现了 23种迁飞昆虫的种类辨识,并分析了昆虫生物学参数的测量误差对迁飞昆虫种类辨识精度的影响,初步验证了利用雷达实现高精度迁飞昆虫种类辨识的可行性.  相似文献   

10.
通过实地调查与文献数据分析,总结了近30年来深圳福田红树林的昆虫群落组成及变化趋势,结合人类活动的影响和土地利用变化,探讨了昆虫群落特征对生境变化的响应。结果表明,不同时期的昆虫群落组成存在较大差异,2012-2013年昆虫群落的种类最丰富,由10目57科113种组成,1993-1994年昆虫群落由9目59科94种组成,1999年和2008-2009年的昆虫种类均较少。20世纪80年代末至90年代,城市建设大量占用和破坏红树林湿地,昆虫种类减少,海榄雌瘤斑螟等害虫种群爆发。2008-2010年,通过开展福田红树林湿地生态系统修复工程,优化了生态系统结构,随后,昆虫多样性在一定程度上得以恢复,种类比以往有明显增多,尤其是天敌昆虫的种类比前期有较大增加。  相似文献   

11.
Non-indigenous species cause great damage worldwide. Non-indigenous insects are known as harmful in many regions, but few comprehensive works have investigated non-indigenous insects as a group. We compiled a comprehensive database of established non-indigenous (ENI) insects in Israel and adjacent regions to investigate how they arrived, their biological characteristics, and the attributes of areas they invade. Of 218 species of ENI insects in this region, 124 are widespread. Most species came as stowaways, but 38 were brought intentionally for biological control. Most ENI insects in this region are in the Coleoptera, Diptera, Hymenoptera, Lepidoptera, and Homoptera. Species from various orders differ in their tendency to be localized or widespread, and in biogeographic origins. The distribution of species among orders differs between native and ENI insects. The Coastal Plain houses the most ENI insect species and the Negev and Judean deserts the fewest. Most ENI insects spread from the Coastal Plain to other regions. Absence of roads, settlements and presence of nature reserves are negatively correlated with occurrence of ENI species. Seventy-nine species are categorized as pests that damage produce, merchandise, forestry, etc. Despite a general dearth of knowledge on impacts of ENI insects on natural systems, 42 species are known to feed on native plants, some of conservation concern. Biological control agents are usually more limited in their distribution than other ENI insects. Further research, legislation, and enforcement are required to minimize effects of these species on agriculture and natural habitats.  相似文献   

12.
Gouws EJ  Gaston KJ  Chown SL 《PloS one》2011,6(3):e16606
Although interspecific body size frequency distributions are well documented for many taxa, including the insects, intraspecific body size frequency distributions (IaBSFDs) are more poorly known, and their variation among mass-based and linear estimates of size has not been widely explored. Here we provide IaBSFDs for 16 species of insects based on both mass and linear estimates and large sample sizes (n ≥ 100). In addition, we review the published IaBSFDs for insects, though doing so is complicated by their under-emphasis in the literature. The form of IaBSFDs can differ substantially between mass-based and linear measures. Nonetheless, in non-social insects they tend to be normally distributed (18 of 27 species) or in fewer instances positively skewed. Negatively skewed distributions are infrequently reported and log transformation readily removes the positive skew. Sexual size dimorphism does not generally cause bimodality in IaBSFDs. The available information on IaBSFDs in the social insects suggests that these distributions are usually positively skewed or bimodal (24 of 30 species). However, only c. 15% of ant genera are polymorphic, suggesting that normal distributions are probably more common, but less frequently investigated. Although only 57 species, representing seven of the 29 orders of insects, have been considered here, it appears that whilst IaBSFDs are usually normal, other distribution shapes can be found in several species, though most notably among the social insects. By contrast, the interspecific body size frequency distribution is typically right-skewed in insects and in most other taxa.  相似文献   

13.
Plant galls - the more we learn, the more there is to know! Approximately 15000 insect species ( c. 2% of all known insects) form galls, and this habit is extremely common over a range of floras and latitudes. Yet, there is still no general consensus on why they exist. Thistle-galling insects are relatively well known and are used as biological control agents (of thistles) and model ecological systems.  相似文献   

14.
《Journal of Asia》2020,23(3):675-679
Bamboos are known as long-living monocarpic plants that exhibit synchronous flowering at long intervals. It has been reported that florivory has a critical effect on their seed production in bamboos, especially in small scale flowering patches. In this study, we aimed to determine species composition and life history of florivorous insects in multiple bamboo species. We collected the inflorescences of 12 bamboo species from 15 sites in Japan from 2017 to 2019 and recorded insect assemblages found in the flowers. Five different insect species were observed to feed on the flowers of bamboo species. Among these, the larvae of two Dicraeus species were the most widely observed florivorous insects of the bamboo species. The other insects included the larvae of Cecidomyiidae sp., which was frequently observed on Sasa species, and the other two insects were Epuraea submicrurula, and Dimorphopterus japonicus. These insects were oviposited on the florets during the budding period. In addition, predators and parasitoids were found in the bamboo flowers. Our findings suggest that the bamboos flowers were mainly consumed by dipteran larvae. Insect species composition and frequency varied among bamboo species and sites. Comparing the frequency of the florivorous insects among bamboo flowering patches, including mass flowering patches, in different areas is needed in future studies.  相似文献   

15.
Antifreeze proteins in Alaskan insects and spiders   总被引:13,自引:0,他引:13  
Prior to this study, antifreeze proteins (AFPs) had not been identified in terrestrial arthropods from the Arctic or anywhere in Alaska. The hemolymph of 75 species of insects and six spiders from interior and arctic Alaska were screened for thermal hysteresis (a difference between the freezing and melting points), characteristic of the presence of AFPs. Eighteen species of insects and three spiders were shown to have AFPs. Ten of the insects with AFPs were beetles including the first species from the families Chrysomelidae, Pythidae, Silphidae and Carabidae. In addition, the first Neuropteran to have AFPs was identified, the lacewing Hemerobius simulans together with the second and third Diptera (the first Tipulids) and the second and third Hemiptera, the stinkbug Elasmostethus interstinctus (the first Pentatomid), and the water strider Limnoporus dissortis (the first Gerrid). Prior to this study, 33 species of insects and three spiders had been reported to have AFPs. Most AFP-producing terrestrial arthropods are freeze avoiding, and the AFPs function to prevent freezing. However, some of the AFP- producing insects identified in this study are known to be freeze tolerant (able to survive freezing) to very low temperatures (-40 to -70 degrees C).  相似文献   

16.
《Ibis》1952,94(3):395-405
Australian records, beginning in 1866, of birds associating with aggressive insects for nesting purposes are assembled. Five species of the genus Gerygone are known to associate with wasps, more or less consistently, in tropical areas, and another species is reported as associating with wasps in the tropics and ants in temperate areas. Such birds deliberately seek the society of the insects, by which they are recognized and tolerated.
If protection is the motive, it would seem to be aimed against reptiles rather than against other birds or mammals. Other possible reasons for the practice ate suggested.
Australian records of insects frequenting birds' nests also are summarized; these include parasites such as the blood-sucking larvae of a fly, together with moth, beetle and fly larvae that serve a beneficial purpose as scavengers, and, in addition, wasps and beetles parasitic on the other insects. On the question of how the insects find the nests at appropriate times, it is suggested that some are guided by odour and others by some undetermined influence.  相似文献   

17.
Invasive non-native plant species often harbor fewer herbivorous insects than related native plant species. However, little is known about how herbivorous insects on non-native plants are exposed to carnivorous insects, and even less is known on plants that have recently expanded their ranges within continents due to climate warming. In this study we examine the herbivore load (herbivore biomass per plant biomass), predator load (predator biomass per plant biomass) and predator pressure (predator biomass per herbivore biomass) on an inter-continental non-native and an intra-continental range-expanding plant species and two congeneric native species. All four plant species co-occur in riparian habitat in north-western Europe. Insects were collected in early, mid and late summer from three populations of all four species. Before counting and weighing the insects were classified to trophic guild as carnivores (predators), herbivores, and transients. Herbivores were further subdivided into leaf-miners, sap-feeders, chewers and gallers. Total herbivore loads were smaller on inter-continental non-native and intra-continental range-expanding plants than on the congeneric natives. However, the differences depended on time within growing season, as well as on the feeding guild of the herbivore. Although the predator load on non-native plants was not larger than on natives, both non-native plant species had greater predator pressure on the herbivores than the natives. We conclude that both these non-native plant species have better bottom-up as well as top-down control of herbivores, but that effects depend on time within growing season and (for the herbivore load) on herbivore feeding guild. Therefore, when evaluating insects on non-native plants, variation within season and differences among feeding guilds need to be taken into account.  相似文献   

18.
ADAPTATIONS OF TERRESTRIAL ARTHROPODS TO THE ALPINE ENVIRONMENT   总被引:3,自引:0,他引:3  
1. The climate changes drastically above the timberline. Diverse adaptations have been evolved by insects and other terrestrial arthropods to survive the alpine environment. The fitness of each species depends on a combination of different factors in accordance with their special habitats. 2. Morphological adaptations such as reduced body-size, are known from a number of alpine insects, increasing their possibility to find sheltered microhabitats. Selection for reduced body size in Andean Phulia spp. butterflies is probably a result of their rigorous environment. Wing atrophy, which is also known in insects from other extreme environments, is widespread in alpine species. In several terrestrial arthropods the absorption of solar radiation is increased by melanism. Increased pubescence, protecting against the loss of heat, is known in alpine butterflies and bumblebees. 3. Several behavioural adaptations are described. Thermoregulatory behaviour is important in many species to raise their body temperatures. Alpine butterflies orient the dark basis of their wings perpendicular to the rays of the sun. Body temperatures of 30 °C may be required for flight. To increase their activities many alpine terrestrial arthropods seek warmer microhabitats in the vegetation and under rocks. The adaptive advantage of nocturnal activity as observed in several species, may be to maintain the water balance or to avoid predation. 4. Tropical alpine terrestrial arthropods are faced with special problems. The large diel temperature fluctuations require cold-hardiness during the night and tolerance to heat during the day. Many species seek sheltered microhabitats under rocks and in vegetation. 5. Due to low precipitation and high evaporation rates many mountain areas are extremely dry. High resistance to desiccation may be very important to alpine species, and in particular to tropical species. Rates of water loss at low relative humidities are comparable to those of desert arthropods. 6. As an adaptation to the cold alpine summers several species of terrestrial arthropods require more than one year to complete their life-cycles. Special to these species is their adaptation to low temperatures in two or more overwintering stages. In spite of their cold surroundings several species have univoltine life cycles, frequently combined with highly specialized adaptations. Increased metabolic rates as a compensation to low temperatures may be widespread in alpine species, but few data are available. 7. Cold tolerance is of particular importance in temperature alpine species. Winter survival in Collembola and Acari depends on supercooling. Great seasonal variations have been observed in a number of species. Freezing tolerance is also known from alpine insects, e.g. in some species of beetles. At high latitudes alpine species must endure periods of up to eight or nine month at low temperatures during hibernation. Anaerobiosis is known from species that are enclosed in ice, with lactate as the main end product of metabolism.  相似文献   

19.
Black soldier fly [BSF; Hermetia illucens L. (Diptera: Stratiomyidae)] larvae are very effective in transforming low-grade food waste into valuable high-end proteins and fat, in intensive production facilities. The production output of this species is growing quickly, but upscaling brings risks to the health status of the reared insects. Until now, not a single major case of disease outbreak caused by a pathogen in a BSF production unit has been reported. This contrasts with data on other species of mass-produced insects, which have experienced various disease outbreaks, indicating that BSFs are comparatively resistant to insect diseases. Further, there are no records of natural infections caused by entomopathogens in BSF. In this review, the known entomopathogens of Diptera, especially BSF, and their potential risks for causing disease in these insects are summarized.  相似文献   

20.
P. W. Price 《BioControl》1972,17(2):211-222
Methods are proposed as a contribution towards the formalization of an approach to the selection and introduction of entomophagous insects. Once the critical resources necessary for the reproduction and survival of a predator or parasitoid have been identified, sites are arranged to sample these insects in different grades of the same critical factor. These grades of a resource may be ranked, and organized on gradients, or unranked, but in both cases the range of samples represents a resource set. The entomophagous insect distributions on these sets are analyzed and quantified by formulae that show the breadth of a species distribution, the similarity between distributions, and the interaction species will experience on each of the resource sets. These calculations can assist in selecting the best species for introduction into an area with a known species composition and distribution.  相似文献   

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