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101.
102.
The vertical stratification of two species-rich moth families (Lepidoptera: Arctiidae, Geometridae) was analysed in a lowland rain forest in Costa Rica. Moths were trapped with automatic 8 W ultraviolet light traps at three sites in the understorey and canopy of a primary forest at the La Selva Biological Station (10.4° N, 84.0° W). A total of 846 arctiid moths (148 species) and 946 geometrid moths (140 species) were analysed. Species richness and diversity of arctiid moths was significantly lower in the understorey than in the canopy (Fisher's alpha: 24 vs. 49) whereas geometrid moths showed an inverse pattern (Fisher's alpha: 44 vs. 27). This resulted in an overall increase in the proportion of conspicuously coloured species towards the canopy. Moth ensembles were clearly separated in multidimensional scaling ordinations, and differed significantly in their faunal composition and dominance between the strata. The available host plant data suggest that the flight height of moths was determined by larval resource availability. Examples include understorey flyers such as the geometrid genus Eois feeding on Piper, and canopy flyers such as the arctiid moth genera Aclytia, Macrocneme and Poliopastea which feed on lianas.  相似文献   
103.
Northern and mountainous ice sheets have expanded and contracted many times due to ice ages. Consequently, temperate species have been confined to refugia during the glacial periods wherefrom they have recolonized warming northern habitats between ice ages. In this study, we compare the gene CYP405A2 between different populations of the common burnet moth Zygaena filipendulae from across the Western Palearctic region to illuminate the colonization history of this species. These data show two major clusters of Z. filipendulae populations possibly reflecting two different refugial populations during the last ice age. The two types of Z. filipendulae only co‐occur in Denmark, Sweden, and Scotland indicating that Northern Europe comprise the hybridization zone where individuals from two different refugia met after the last ice age. Bayesian phylogeographic and ecological clustering analyses show that one cluster probably derives from an Alpe Maritime refugium in Southern France with ancestral expansive tendencies to the British Isles in the west, touching Northern Europe up to Denmark and Sweden, and extending throughout Central Europe into the Balkans, the Peleponnes, and South East Europe. The second cluster encompasses East Anatolia as the source area, from where multiple independent dispersal events to Armenia, to the Alborz mountains in north‐western Iran, and to the Zagros mountains in western Iran are suggested. Consequently, the classical theory of refugia for European temperate species in the Iberian, Italian, and Balkan peninsulas does not fit with the data from Z. filipendulae populations, which instead support more Northerly, mountainous refugia.  相似文献   
104.
The Cossidae are an economically important family of moths consisting of six subfamilies and more than 700 species globally. Their larvae are often of serious concern to forestry and horticulture in that they are known to bore in the branches and trunks of a wide range of trees and shrubs. Cossulinae is one of the six subfamilies of Cossidae and is restricted to the New World. As a result of this revision, the Costa Rican Cossulinae has been found to consist of five genera and 18 species. The phylogenetic relationships of all Cossulinae genera were analysed using the computer programs WinClada and NONA. Glandular organs new to Cossidae and the Lepidoptera have also been discovered. Four genera, Biocellata gen. nov. , Magulacra gen. nov. , Simplicivalva gen. nov. and Spinulata gen. nov. , and the following nine species are described as new: Biocellata bifida sp. nov. , Biocellata davisorum sp. nov. , Cossula buspina sp. nov. , Cossula duplexata sp. nov. , Cossula longirostrum sp. nov. , Cossula minutiloba sp. nov. , Simplicivalva ampliophilobia sp. nov. , Spinulata oblongata sp. nov. and Spinulata quasivinnea sp. nov. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 154 , 222–277.  相似文献   
105.
The pollination process and breeding system of the sympatric Habenaria johannensis, H. macronectar, H. megapotamensis and H. montevidensis was documented for native populations from Rio Grande do Sul, Brazil. All species investigated offer a nectar reward (mean values of total sugars ranging from 18 to 26%) concealed in a spur. Habenaria montevidensis is pollinated by butterflies (Hesperiidae, especially of the genus Urbanus) that carry pollinaria on their eyes; the other three species are pollinated by Sphingidae. Habenaria johannensis is pollinated by the moths Manduca rustica and M. sexta that carry the pollinaria at the base of the proboscis. Habenaria macronectar is pollinated by the moths Eumorpha labrusca and M. cf. lucetius, and these bear pollinaria between the palpi. Habenaria megapotamensis is pollinated by moths of M. cf. lucetius that bear the pollinaria on the proboscis. All species studied are self‐compatible, but pollinator dependent. They also displayed high reproductive success (ranging from 69.48 to 97.40%) and male efficiency factors slightly higher than 1, suggesting that at least one flower was pollinated for each flower acting as pollen donor. At the study sites, the investigated Habenaria spp. are isolated (in terms of pollination) by a set of factors that includes differing floral morphologies, different pollinators and/or different pollinarium placement on the pollinator. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, ??, ??–??.  相似文献   
106.
Moths from the superfamily Geometroidea were collected using standard Rothamsted light-traps at three levels on a tower (i.e. 1, 15, and 30 m) concurrently monthly for thirteen months in a lowland dipterocarp forest in Peninsular Malaysia. There was no consistently significant difference in species richness, abundance and diversity (as measured by from the log-series) for individual sampling months between the three levels although values tended to be lower at the highest level. The diversity for the canopy (high) level was significantly lower when all samples were pooled. Here plant diversity is lower and the forest architecture is less complex. The geometroid moths are uniformly distributed throughout the three levels, with indications of preference for canopy or ground-level flight for some higher taxa. Some groups, such as Geometrinae, show much narrower vertical flight patterns than do others, such as Boarmiini. No significant coincidence of flight preference levels within distinct strata was detected.  相似文献   
107.
空间分布型的研究是现代理论生态学的重要基础工作之一,它在实际应用上亦具重要意义。它不仅可揭示出种群的空间结构特征,而且还是确定抽样技术、资料代换和正确估计种群数量的基础。 目前,国内外有关昆虫空间分布型的研究多限于农林业害虫,对其它昆虫的空间分布研究甚少。虫草蝠蛾是我国名贵中药材冬虫夏草的寄主昆虫,主要分布在青海、西藏、四川、云南四省境内的高山草甸。近年来,冬虫夏草产量逐年下降,远远不适应市场的需求,更因自然资源日趋减少,大有枯竭之势。为挽救这一珍贵资源昆虫,急待尽  相似文献   
108.
Leafmining insects have extraordinarily intimate relationships with their host plants and are therefore prime candidates for potential ecological speciation in sympatry, but how commonly this mode of speciation occurs in any group of life remains debated. Prior research on the pygmy moth (Nepticulidae) genus Ectoedemia using morphology, DNA barcoding, and multi-marker phylogenetic approaches left two unresolved species complexes, each with each four described species. In this study, we thoroughly sampled each complex across a range of host plants and localities across Europe. We used a double digest restriction-site associated DNA (ddRAD) sequencing approach to clarify species boundaries. In the E. rubivora complex, ddRAD data resolved all four species, contrary to morphological and COI data, which supports a potential scenario of host plant-driven speciation where the host plant specialization provides an ecological barrier to hybridization. However, we found no indication of host race formation within the oligophagous E. atricollis (Stainton). In the E. subbimaculella complex, SNP data only partly distinguishes between the parapatric E. subbimaculella (Haworth) and E. heringi (Toll), but with some statistical overlap, suggesting incomplete lineage sorting which may represent early phases of host-based ecological speciation, or admixture following a period of isolation.  相似文献   
109.
虫草蝠蛾触角感觉器的扫描电镜观察   总被引:9,自引:0,他引:9  
本文报道冬虫夏草的三种寄主昆虫白马蝠蛾(Hepialus baimaensis)、 人支蝠蛾(H.Renzhiensis)和中支蚯蛾(H.Zhongzhiensis)触角感觉器种类、形态和分布的扫描电镜观察结果。三种蝠蛾触角表面均缺少网状覆盖物。计有七种感觉器,名称为毛形感器、刺形感器、锥形感器、腔锥感器、Bohm氏鬃毛、鳞形感器和钟形感器。毛形感器分A和B型,数量最多。鞭节上每节具有2-3只刺形感器和l-5只锥形感器。腔锥感器分为长栓和短栓两种形态类型,腔周围都无缘栓。 Bohm氏鬃毛主要分布于基节,数量较多。钟形感器仅在雄蛾触角上见到。各类感觉器在种间无明显差异。  相似文献   
110.
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