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正胆小的人见到六条腿的昆虫时常常会发出惊声尖叫,但有些模样奇特的昆虫在让人厌恶害怕的同时,也让人感叹大自然的奇妙造化。这些昆虫奇特的身体形态令人费解,连科学家也不知道为什么。长颈象鼻虫这种昆虫被叫作"长颈象鼻虫"的原因显而易见。只要看看这小家伙伸出来的比身子还要长的脖子,就知道它是名副其实的长颈昆虫。雄性长颈象鼻虫的脖子比雌性更长,长脖子是它 相似文献
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本文报道了近年来发现于我国湖南省和贵州省的一种新毒菌,经鉴定是叶状耳盘菌Cordierites frondosa(Kobay.) Korf。 相似文献
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LIUJianni SHUDegan HANJian ZHANGZhifei 《科学通报(英文版)》2004,49(10):1063-1071
The origin of arthropods has long been one ofthe most hotly-debated subjects. Arthropods used to bethought closely related with annelids, but the two groups arenow believed to be separated into two major realms withinProtostomia on the basis of new molecular data. Although itis generally held by paleontologists that arthropods should berooted in the early lobopods-.a kind of worm-like creaturewith non-segmented legs, no intermediate forms have beenfound to bridge them. Here we report an organism with amixture of characters, including features characteristic ofarthropods (e.g., primary cephalization with paired eyes,paired antennae, and preliminary tagmosis) and of lobopods(e.g., worm-like body design, the dorsal spines, andnon-segmented limbs or lobe-like legs). The discovery of therare transitional form may throw new light on the origin ofarthropods and suggests that the most primitive arthropodsbegan with paired uniramous legs and the biramous onesevolved later. 相似文献
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LIU Jianni HAN Jian SIMONETTAA. M. HU Shixue ZHANG Zhifei YAO Yang SHU Degan 《科学通报(英文版)》2006,51(3):358-363
Facivermis yunnanicus (Hou & Chen, 1989), from the Early Cambrian Chengjiang Lagerstatte, a worm-like fossil with 5 pairs of tentacles and a perceived shrunken end, has been regarded as related to polychaetes, later it has been variously interpreted as Iobopods, Pentastoma and Iophophorates. Newly discovered complete specimens by the ELI field team show that the taxon has, in addition to the 5 pairs of appendages, a pear-shaped trunk end bearing two or three circles of hooks. Accordingly based on these important morphological characters, reconsideration of its affinities is provided and the taxonomy is remedied herein. Because the five pairs of appendages of Facivermis yunnanicus resemble the appendages of the fore-trunk of Iobopod Miraluolishania (Liu & Shu, 2004), it seems that they are homologous structures. Therefore, the affinities of Facivermis are regarded here as being close to the Iobopods, in addition, the lobe-like appendages of Facivermis are very crucial to exploring the origin of the appendages of Iobopods and arthropods. 相似文献
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康积行 《福州大学学报(自然科学版)》1980,(2):73-82
本文从理论上简要地分析了铁水翻花的机理和各类花纹的内在联系,并进行了分类,归纳了四种基本形花纹的特点,同时总结了铁水的碳硅含量等因素对花纹形状的影响,进而提出了与花纹形状相对应的铁水碳硅含量范围和相当的铁水牌号。为进行普通灰铸铁的炉前检验与材质控制时提供参考。 相似文献
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通过调控大型水族环境理化因子并模拟海洋生态,对叶状蔷薇珊瑚(Montipora folio sa)进行人工培育.进行了4组实验,珊瑚生长结果:M1组(1.40±0.10)cm/月、M2组(1.80±0.45)cm/月、M3组(1.50±0.16)cm/月、M4组(1.90±0.79)cm/月,平均生长速率为(1.60±0.24)cm/月.表明,该品种珊瑚能够在人工环境调控下进行较快速的生长.在本研究中,叶状蔷薇珊瑚明显比其他属种珊瑚(裸肋珊瑚等)生长速率快,可作为1个品种进行人工增殖,为自然海域的珊瑚群恢复提供物质基础和理论支撑.叶状蔷薇珊瑚被称为海底之花,其形状美丽如牡丹花、个体也比较大可作为海下旅游观览资源.叶状蔷薇珊瑚抗病力强,通过人工增殖恢复已被破坏的珊瑚生态系,能实现可持续发展的绿色海下旅游产业,服务于国际旅游岛的建设. 相似文献