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1.
The Lithuanian bat fauna includes 14 species. Myotis daubentoni, Pipistrellus nathusii, Plecotus auritus and Eptesicus serotinus are the most abundant and widespread species, although recently P. auritus has disappeared from some hibernacula. There are still abundant populations of Myotis nattereri, Myotis brandti and Barbastella barbastellus in hibernacula, while their status in summer is unknown. Myotis dasycneme is probably very rare and endangered. The status of Myotis mystacinus and Nyctalus leisleri is not clear, but they are most likely very rare because very few specimens have been found. So far little is known about status of Nyctalus noctula, Pipistrellus pipistrellus, Eptesicus nilssoni and Vespertilio murinus because these species are common only during autumn bat migration along the Baltic Sea coast. Two other species, Myotis bechsteini and Rhinolophus hipposideros, have been rejected from the list of bats of Lithuania, because old references to records of these species were not reliable. From what is currently known it seems that: (i) the northern limits of distribution of B. barbastellus and E. serotinus reach the middle of Lithuania between 55°N and 56°N, which may also be the southern limit of abundance of E. nilssoni; (ii) the wintering site with the largest numbers of bats in Lithuania is the vaults of Kaunas fortress, where every year eight species are found hibernating in numbers estimated as follows: M. daubentoni 400–500, M. nattereri 200–300, M. brandti 80–100, B.barbastellus 200–300, P. auritus 40–60, M. dasycneme 15–20 and a few E. serotinus and E. nilssoni. In Lithuania nine bat species have been protected by law since 1991, as species included in the Red Data Book. Also 11 bat reserves have been designated in Kaunas fortress to protect the most important hibernation sites in Lithuania.  相似文献   
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2021年8月分别在湖南省长沙市天心区大托站立交桥底和昭华湘江大桥底捕获2只鼠耳蝠(2♂,标本号211521和211540),经鉴定为霍氏鼠耳蝠(Myotis horsfieldii),为湖南省蝙蝠分布新记录物种。本次捕获标本体型中等偏小,前臂长分别为36.1 mm(211521)和33.1 mm(211540),头体长为44.0 mm和41.2 mm,后足长(10.5 mm和10.4 mm)超过胫骨长(16.4 mm和16.2 mm)的一半,耳屏长(5.1 mm和3.8 mm)不及耳长(12.5 mm和10.0 mm)的一半;头骨狭长,颅全长15.5 mm和15.0 mm,脑颅宽7.8 mm和7.5 mm,颅骨纤弱,额骨处有明显倾斜,脑颅高于上颌骨,颧弓较细。与来自泰国和印度尼西亚的霍氏鼠耳蝠标本相比,前臂长、头体长和尾长测量数据偏小,但头骨测量数据接近。基于Cyt b基因序列的系统发育分析表明,此次捕获的鼠耳蝠标本与霍氏鼠耳蝠聚类在一起,与来自香港的霍氏鼠耳蝠样本遗传距离仅为0.9%,故确定该物种为霍氏鼠耳蝠。标本保存于广东省科学院动物研究所。  相似文献   
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We investigated the population genetics of seven maternity roosts of Bechstein’s bats widely distributed across the south of England. Across all of the populations sampled, two mitochondrial DNA microsatellite loci were fixed for single haplotypes. Genetic diversity across eight nuclear microsatellite loci was similar in all seven populations, with a mean He of 0.727. However, six of the populations showed substantial homozygote excess, with F IS estimates greater than zero, indicative of recent inbreeding. Bottleneck tests also implied that six of the populations have experienced recent declines. Genetic differentiation among the populations was low, with a mean intersite F ST estimate of 0.041. There was no significant isolation by distance using allele frequency-based criteria (F ST and genetic distances), however, a weak correlation was found using the allele size-based R ST criterion. Assignment tests were unable to distinguish the seven sampling sites as distinct clusters. Mean intra-roost relatedness (r) was 0.079, indicative of recent inbreeding relative to German populations. All but one of the bats had one or more half or full siblings in its maternity roost. In addition, family relationships of individuals within a colony were significantly commoner than family relationships among four proximal roosts <8 km apart. The results are discussed in the context of conservation requirements for this rare British bat.  相似文献   
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The distribution and ultrastructure of Merkel cells were described in detail in piscivorous bats through immunohistochemistry and transmission electron microscopy techniques. The findings indicated that Merkel cells are commonly found in raised-domes,hair follicles and in the basal epidermis of the skin from their back,abdomen,intercrural membranes,wing membranes and footpads. However,the density of Merkel cells is significantly higher in the footpad than in other places. These results suggested that there ...  相似文献   
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北京房山大足鼠耳蝠食鱼性及回声定位信号   总被引:8,自引:1,他引:7  
大足鼠耳蝠 (Myotisricketti)具有食鱼蝙蝠的形态特征 ,但食鱼习性待考。以北京房山种群为对象 ,夜间在洞口悬挂雾网 ,捕获取食返洞大足鼠耳蝠共 18只 ,胃检发现 7例全为鱼类 (宽鳍 ,鲫鱼和洛氏 ) ,10例以鱼类为主 ,仅 1例全为昆虫。室内实验观察到捕鱼行为 2 5 6次 ,成功率 12 5 %。如此 ,该种具食鱼习性的猜测得到证实。回声定位信号属调频型 ,扫频范围从 6 7 4 0kHz到 2 3 6 3kHz ,主频 (38 2 1± 1 18)kHz ,声信号时程 (2 5 8± 0 34)ms。这些特征具有一定的物种特异性  相似文献   
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大足鼠耳蝠的分布   总被引:7,自引:0,他引:7  
马杰  戴强  张树义  沈钧贤  梁冰 《四川动物》2003,22(3):155-156
首次报道北京、成都和广东发现大足鼠耳蝠,并结合文献对其形态特征及其在我国现有分布区进行了描述。  相似文献   
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We studied food intake of and estimated ingested energy in female and male Myotis daubentonii during the periods of pregnancy (period 1, 8 May–4 June) and of intense spermatogenetic activity (period 2, 24 July–22 August) over 8 years (1996–2003) in central Germany. We used radiotelemetry to determine the time spent foraging and marked animals with chemiluminescent light-sticks to determine prey attack rates. Body length, body mass, moisture content, and caloric content of chironomids, the main prey of Daubenton’s bats, were measured to estimate the nightly food intake and, in consequence, energy intake. Pregnant females spent significantly more time foraging than males during period 1 and females during the post-lactation period. In contrast, male foraged longer during the period of highest spermatogenetic activity than during late spring and also significantly longer than post-lactating females. Based on a mean number of 8.3 prey attacks per minute, the time spent foraging, and a capture success rate of either 50 or 92%, calculated intake values with a feeding rate of 7.6 insects per minute (=92% capture success) were more consistent with literature data for other insectivorous bats than that of values calculated on the basis of a capture success rate of 50%. In the high capture-success model, calculated insect intake of female bats was 8.0 g during pregnancy and 4.9 g per day during post-lactation, providing 5.0 and 3.0 kJ of ingested energy per gram body mass per day. Calculated intake of male bats was 3.6 g insects per day during late spring and 8.0 g during period of intensive spermatogenesis, providing 2.6 and 5.7 kJ of ingested energy per gram body mass.  相似文献   
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