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1.
野生唐鱼在广东的再发现   总被引:13,自引:1,他引:12       下载免费PDF全文
唐鱼(Tanichthys albonubes Lin)又称白云金丝、白云山鱼,是我国特有的国家二级保护野生动物,在发现时个体数量已属稀少;近代仅分布于广州白云山及附近的山溪中;近20年来,无野外发现该种的报道,被认为野生种群已经灭绝。作者在2003年9月在广州的山溪中发现了该种的野生种群,并对该野生种群的形态、食性、生境、生长和繁殖做了初步研究,分析了致危因素,提出了保育措施。  相似文献
2.
复边藓属 (Cinclidotus)植物为水湿生藓类 ,其中文名是指叶片边缘有多层细胞构成厚边之意。该属植物多生于山区的流水中 ,附着于石上或树基部。本属全世界有 9种 (Wijk ,195 9;Crosby等 ,1992 ;Crosby等 ,1999) ,分布于南北半球的温带及暖热地区 (陈邦杰等 ,1963)。由于该属植物形态特征和生境条件较为特殊 ,苔藓学界对其系统位置一直有不同的看法和处理。我国复边藓属植物记录仅 1种 ,即Cinclidotusfontinaloides (Hedw )P Beauv ,产西藏喜玛拉雅地区(Mitten ,185 9)…  相似文献
3.
According to recent literature, five of the six known Austrian conchostracan species are extinct. However, interim results of a current study on large freshwater branchiopods in Austria show that five species still occur at a restricted number of sites in the Pannonian region of Lower Austria. The clam shrimps Leptestheria dahalacensis and Eoleptestheria ticinensis were rediscovered in May 1994 in the flood plains of the river Morava near Marchegg. Imnadia yeyetta and Cyzicus tetracerus have been known to the authors in the same region since 1981, and 1992, respectively. Limnadia lenticularis occurs in the flood plains of the rivers Morava and Danube. Lynceus brachyurus, the only Austrian representative of the Laevicaudata, was not found and most probably got extinct. All Austrian clam shrimp species are considered to be endangered. Main threats are agricultural activities and artificial changes of the hydrologic conditions. Conservational measures are discussed for their effectivity.  相似文献
4.
In 1889 Hugo de Vries published Intracellular Pangenesis in which heformulated his ideas on heredity. The highexpectations of the impression these ideaswould make did not come true and publicationwas negated or reviewed critically. From thereactions of his Dutch colleagues and thediscussion with the famous German zoologistAugust Weismann we conclude that the assertionthat each cell contains all hereditary materialwas controversial and even more the claim thatcharacters are inherited independently of eachother. De Vries felt that he had to convincehis colleagues of the validity of his theory byproviding experimental evidence. He establishedan important research program which resulted inthe rediscovery of Mendel's laws and thepublication of The Mutation Theory.This article also illustrates somephenomena that go beyond an interesting episodein the development of theories of heredity. Itshows that criticism from colleagues can move aresearcher so deeply that he feels compelled toset up an extensive research program. Moreoverit illustrates that it is not unusual that acreative scientist is only partially willing totake criticism on his theories into account.Last but not least it demonstrates that commonopinion on the validity of specific argumentsmay change in the course of time.  相似文献
5.
    
Onobrychis aliacmonia was discovered in 1956 and described in 1973, the year when it was last collected. Its single known locality was flooded soon afterward by an artificial lake now extending over the middle portion of the Aliakmon Valley (western Greek Makedhonia), and the species was believed extinct. It has now been rediscovered in the southern Peloponnisos, in an area far south of the locus classicus and in a widely different ecological context.Dedicated to Hofrat Univ.-Prof. DrK. H. Rechinger on the occasion of his 80th birthday.  相似文献
6.
通过对模式标本的考订,指出大苞茶的原始描述中关于子房特征的部分与模式标本的实际性状不符,对其形态特征进行了修订。基于修订后的形态特征,该“绝迹”物种在模式产地的周边地区被重新发现。  相似文献
7.
陕西羽叶报春为现存的珍惜濒危植物之一。自1904年W.Filchner在秦岭南坡采集到模式标本后再未在野外发现,植物界一度认为其已经绝灭。2006年于湖北省再次发现。作者于2015年3月在其模式产地秦岭南坡的陕西省洋县秧田乡重新发现该物种,并对其花器官形态和生境等进行了补充描述。  相似文献
8.
王焕冲  和兆荣  孙航 《广西植物》2012,32(3):315-317
报道了蔷薇科两种悬钩子属植物在中国的重新发现,分别为美叶悬钩子(Rubus calophyllus C.B.Clark)和拟针刺悬钩子(R.parapungens H.Hara),并提供了简要的描述和标本照片。  相似文献
9.
喜雨草,湖南珍稀特有植物,属唇形科单型属喜雨草属,自1918年8月韩马迪在湖南西南部武冈云山采到模式标本,并于1936年作为一个新属、新种发表后,其踪迹消失全无。该次报道为喜雨草被发现近100年后,在湖南宁远、通道、道县、新宁被重新发现。根据采集的标本和拍摄的照片,更正修改和补充了原形态描述,重新确定了该种花萼为3/2式,花冠颜色为白色。  相似文献
10.
2006年6月份和9月份,作者在对重庆市城口县大巴山地区进行考察时,采集到了中国特有种川东灯台报春(Primula mallophylla)的标本,这是近百年来对该种除模式标本外的再度发现。根据在大巴山观察及采集到的材料,作者对过去该种的特征描述中存在的一些疑问进行了澄清,更正和补充了其形态描述;对历史上混淆的几个种列出了检索表;报道了该种的染色体数目及核型;根据国际通用的“红色名录等级及标准”对其濒危等级进行了评估。  相似文献
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