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21.
Integrated species delimitation and conservation implications of an endangered weevil Pachyrhynchus sonani (Coleoptera: Curculionidae) in Green and Orchid Islands of Taiwan 下载免费PDF全文
YEN‐TING CHEN HUI‐YUN TSENG MING‐LUEN JENG YONG‐CHAO SU WEN‐SAN HUANG CHUNG‐PING LIN 《Systematic Entomology》2017,42(4):796-813
Oceanic islands are productive habitats for generating new species and high endemism, which is primarily due to their geographical isolation, smaller population sizes and local adaptation. However, the short divergence times and subtle morphological or ecological divergence of insular organisms may obscure species identity, so the cryptic endemism on islands may be underestimated. The endangered weevil Pachyrhynchus sonani Kôno (Coleoptera: Curculionidae: Entiminae: Pachyrhynchini) is endemic to Green Island and Orchid Island of the Taiwan‐Luzon Archipelago and displays widespread variation in coloration and host range, thus raising questions regarding its species boundaries and degree of cryptic diversity. We tested the species boundaries of P. sonani using an integrated approach that combined morphological (body size and shape, genital shape, coloration and cuticular scale), genetic (four genes and restriction site‐associated DNA sequencing, RAD‐seq) and ecological (host range and distribution) diversity. The results indicated that all the morphological datasets for male P. sonani, except for the colour spectrum, reveal overlapping but statistically significant differences between islands. In contrast, the morphology of the female P. sonani showed minimum divergence between island populations. The populations of P. sonani on the two islands were significantly different in their host ranges, and the genetic clustering and phylogenies of P. sonani established two valid evolutionary species. Integrated species delimitation combining morphological, molecular and ecological characters supported two distinct species of P. sonani from Green Island and Orchid Island. The Green Island population was described as P. jitanasaius sp.n. Chen & Lin, and it is recommended that its threatened conservation status be recognized. Our findings suggest that the inter‐island speciation of endemic organisms inhabiting both islands may be more common than previously thought, and they highlight the possibility that the cryptic diversity of small oceanic islands may still be largely underestimated. 相似文献
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Dissipative particle dynamics (DPD) was carried out to study systems containing gold atoms, organic ether (oligohydroquinonyl ether terminated with a thiol group) and organic solvents. The components in the simulated system are very different in size and chemical nature. Our simulation showed that the reproduction of the macroscopic experimental phase separation, properly dividing the polymeric molecule into beads, selecting the size of gold bead, and choosing the appropriate interaction parameters between beads are crucial. In addition, the solvent effect was the dominant factor for the formation of spherical aggregates of Au atoms and organic ether molecules. We report the interaction strengths between the solvent and gold clusters. Our work has demonstrated that DPD methods can be applied to the study of complex meso-scale systems. 相似文献
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我国广东路氏锥虫的研究Ⅰ.种的特性及其在实验寄主中的繁殖 总被引:1,自引:0,他引:1
本文对发现于广东的鼠锥虫进行了寄主特异性、形态学、实验寄主体内的感染过程、厦虫氨基酸组分等多方面的研究,并将其定为路氏锥虫在中国广东分布的一个不同地域株。本文研究了它在实验寄主体内繁殖消长的规律,整个发育过程的各期形态及成熟期的超微结构,并测出其16种氨基酸的存在和含量。 相似文献
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A. Ya. Ivanov 《Neurophysiology》1987,19(5):495-501
Tonic activity in rabbit superior cervical ganglion neurons was investigated using intracellular recording techniques as well as changes produced when the animal breathed a gaseous mix with a raised CO2 level. The test neurons were divided into three groups depending on the pattern of their tonic activity and reflex change. Action potentials were produced by the activity of dominant and accessory preganglionic inputs in the firing pattern of all neuronal groups, implying the existence of other types of inputs into the neurons innervating different organs. Having analyzed changes in action potential rate and EPSP in the tonic activity of neurons from different groups, it was presumed that preganglionic fibers with a similar activity pattern converge on the majority of neurons in each group.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 19, No. 5, pp. 665–672, September–October, 1987. 相似文献
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胆碱能神经对人餐后神经降压素释放的影响 总被引:2,自引:0,他引:2
本文比较了6名健康成人进食、餐前肌注阿托品以及单纯咀嚼食物后的血浆神经降压素样免疫活性物质(NTLI)水平的变化,以探讨胆碱能神经对神经降压素释放的影响。用放射免疫测定法分别测定NTLI和胰多肽(PP)的含量,以便同时比较两者释放的状态。6人的基础血浆NTLI和PP的水平平均分别为15.7±2.4和16.6±9 7pmol/L。进食后,血浆NTLI和PP水平均显著增高,并呈双相反应。第一个血浆NTLI高峰平均为60.7±13.2pmol/L,出现于餐后的20min。餐后90min,又出现另一个高峰,其平均水平为58.8±8.2pmol/L。在进食前肌注阿托品1mg,餐后的第一个血浆NTLI高峰消失,而第二个高峰仍存在。单纯咀嚼食物后,血浆PP水平明显增高,而对NTLI的释放无刺激作用。本文结果提示,餐后早期的神经降压素释放的调节是由非迷走胆碱能神经参与的,而后期的释放不受胆碱能神经的影响。 相似文献
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