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1.
The reptile fauna of Romania comprises 23 species, out of which 12 species reach here the limit of their geographic range. We compiled and updated a national database of the reptile species occurrences from a variety of sources including our own field surveys, personal communication from specialists, museum collections and the scientific literature. The occurrence records were georeferenced and stored in a geodatabase for additional analysis of their spatial patterns. The spatial analysis revealed a biased sampling effort concentrated in various protected areas, and deficient in the vast agricultural areas of the southern part of Romania. The patterns of species richness showed a higher number of species in the warmer and drier regions, and a relatively low number of species in the rest of the country. Our database provides a starting point for further analyses, and represents a reliable tool for drafting conservation plans.  相似文献   
2.
R. Meyer  W. Nagl 《Protoplasma》1993,172(2-4):132-135
Summary Video-densitometric DNA measurements of Feulgenstained tissues of 42 day old eggs of the corn snake,Elaphe g. guttata (Columbridae, Serpentes), revealed a basic DNA content of 2C=2.17 pg, with somatic polyploidy in the allantois, the chorioallontois, the yolk sac, and other extraembryonic membranes. The maximum value determined was 128C (in binucleate cells 2×128C) at the distal pole of the egg. This is the first report of somatic polyploidy in a snake, and one of the first in reptiles in general.  相似文献   
3.
Fasolo  A.  Franzoni  M. F. 《Cell and tissue research》1983,230(2):387-400
Summary An analysis of the preoptic area of the lizard, Lacerta sicula R., with the use of the Golgi method revealed that: 1)in principle, the dendritic pattern of its neurons is relatively simple; 2) the supraoptic nucleus contains large- to medium-sized bipolar or multipolar neurons together with small, usually multipolar nerve cells; 3) the preoptic periventricular gray and the paraventricular nucleus exhibit a varied neuronal typology, including large multipolar or bipolar elements, abundant CSF-contacting neurons, and some tufted elements; and 4) the lateral regions display some conspicuous multipolar neurons.With a financial contribution from Ministero della Pubblica Istruzione  相似文献   
4.
The East Usambara Mountain forests constitute what is probably one of the richest biological communities in Africa in terms of plant and animal species numbers and endemic taxa. This review presents brief accounts of the flora and of three invertebrate and four vertebrate groups and shows the percentage endemic taxa to vary from 2% (mammals) to 95% (millipedes) as a proportion of the true forest species. Notes are given on the geology, soils, climate and present land use of the Usambaras. Biological richness is considered to be due to long periods of isolation and geological stability coupled with periods of species immigration during times of re-establishment of a continuous forest cover. The nature of the endemic elements is briefly discussed. Evidence is given to show that the forests are subject to increasing pressure from legal and illegal encroachment due to agriculture (tea, cardamon, subsistence) and forestry timber operations. Air photograph analysis shows a forest decrease of some 50% in the vicinity of Amani from 1954 to 1976. The low conservation status of most forest reserves and the lack of detailed knowledge on the distribution, status and biology of the endemic species means present conservation efforts are poor and haphazard. This review calls for greatly increased research inputs and a complete halt to all exploitation of natural forest areas until a long term conservation land use plan can be implemented.  相似文献   
5.
华北丽斑麻蜥食物同化和疾跑速的热依赖性   总被引:4,自引:4,他引:4  
罗来高  屈彦福  计翔 《动物学报》2006,52(2):256-262
作者研究山西阳泉丽斑麻蜥(Eremias argus)成体的选择体温、热耐受性及食物同化和疾跑速的热依赖性。选择体温、临界低温和临界高温无显著的两性差异,分别为36·0℃、1·0℃和44·9℃。在实验温度范围内,体温显著影响食物通过时间、日摄食量、日粪尿排量、表观消化系数和同化效率。食物通过时间在26 -34℃范围内随体温升高而缩短,在更高的体温下则延长。蜥蜴在30、32、34和36℃体温下明显摄入较多的食物、排出明显较多的粪尿。34℃和36℃下的表观消化系数和同化效率大于其它更低或更高温度下的对应数值,但这两个变量未因体温变化而呈现清晰的规律性变化。疾跑速在18 -36℃范围内随体温升高而加快,在38℃体温下则减缓。36℃或附近体温最适合疾跑速。疾跑速最适体温接近蜥蜴的选择体温,表明蜥蜴疾跑速的最适温度可能与其选择体温密切相关[动物学报52 (2) : 256 -262 , 2006]。  相似文献   
6.
广东省曲江县发现鳄蜥   总被引:5,自引:2,他引:5  
报道了首次发现于广东的鳄蜥的形态结构特征,并将它与广西的鳄蜥进行了比较。  相似文献   
7.
2010年6月2日,在广东省韶关市始兴县车八岭国家级自然保护区采集到蜥蜴幼体标本1号,经鉴定为海南棱蜥(Tropidophorus hainanus),为广东省爬行动物新纪录,标本保存在华南濒危动物研究所。  相似文献   
8.
Summary The adrenergic innervation of the pulmonary vasculature of the file snake Acrochordus granulatus was examined by use of glyoxylic acid-induced fluorescence. Perivascular plexuses of blue-green fluorescent nerves are observed around the common pulmonary artery, the anterior and posterior pulmonary arteries, the arterioles leading to the gas exchange capillaries of the lung, the venules draining the lung, and the anterior and posterior pulmonary veins. Adrenergic nerves are also associated with the visceral smooth muscle of the lung septa and other tissues. Thus, adrenergic control of pulmonary blood flow may occur either at the common pulmonary artery or more regionally within the lung. Regional control of blood flow in the elongate lung of this snake may be important in matching pulmonary perfusion with the distribution of respiratory gas. Glyoxylic acid-histochemistry and immunohistochemistry revealed that populations of cells located in the common pulmonary artery contain the indoleamine 5-hydroxy-tryptamine. Many of the cells are intimately associated with varicose blue-green fluorescent nerves. It is proposed that the 5-hydroxytryptamine-containing cells may be involved in intravascular chemoreception.  相似文献   
9.
A recent molecular phylogeny of the Arid clade of the genus Hemidactylus revealed that the recently described H. saba and two unnamed Hemidactylus species from Sinai, Saudi Arabia and Yemen form a well-supported monophyletic group within the Arabian radiation of the genus. The name ‘Hemidactylus saba species group’ is suggested for this clade. According to the results of morphological comparisons and the molecular analyses using two mitochondrial (12S and cytb) and four nuclear (cmos, mc1r, rag1, rag2) genes, the name Hemidactylus granosus Heyden, 1827 is resurrected from the synonymy of H. turcicus for the Sinai and Saudi Arabian species. The third species of this group from Yemen is described formally as a new species H. ulii sp. n. The phylogenetic relationships of the members of ‘Hemidactylus saba species group’ are evaluated and the distribution and ecology of individual species are discussed.  相似文献   
10.
Abstract

We here describe new remains of amphibians and reptiles from the early Miocene (MN 4) of two different Greek localities, Aliveri and Karydia. The newly described material consists of urodelans, alytids, indeterminate anurans, turtles, crocodylians, lacertids, indeterminate scincomorphs, anguids, colubrids, viperids, and indeterminate snakes. The presence of the frog Latonia cf. gigantea in Greece is documented for the first time. Additionally, the presence of viperids in Aliveri implies a much wider distribution for these snakes during the early Miocene of Europe. Of special interest is the presence of a peculiar colubrid that seems to possess a hitherto unknown vertebral structure, which is herein defined as the ‘paracentral ridge’. Although incomplete, the new material has important taxonomic and biogeographic implications, as it enhances our understanding of southeastern European herpetofaunas from the early Miocene, a time period that was characterised by major dispersal and extinction events and climatic change that affected the whole continent.  相似文献   
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