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1.
横断山齿突蟾属一新种(两栖纲:锄足蟾科)   总被引:2,自引:0,他引:2  
1982年在横断山区考察期间,发现四川木里截族自治县的齿突蟾Scutiger标本在第二性征、趾蹼等特征与已知的各种齿突蟾均不相同,描述为新种木里齿突蟾Scutiger muliensis。  相似文献   

2.
2016年4—6月在贵州梵净山国家级自然保护区(108°46'8.07″E,27°50'56.77″N,海拔539 m)和雷公山国家级自然保护区(108°11'47.2″E,26°22'42.24″N,海拔1 687 m)采集到2号两栖动物标本。经形态特征比较,与武陵掌突蟾Leptobrachella wulingensis相似。基于线粒体16S rRNA基因构建的掌突蟾属Leptobrachella部分物种系统发育树显示,此次采集的标本与武陵掌突蟾聚为一支。基于Kimura双参数模型估算本次采集的标本与武陵掌突蟾模式产地标本间的遗传距离为1.6%,小于掌突蟾属物种间的遗传距离。综合形态学和系统发育比较,确定此次采集到的掌突蟾标本为无尾目Anura角蟾科Megophryidae掌突蟾属的武陵掌突蟾,系贵州省两栖动物新记录种。  相似文献   

3.
2021年5月在广西隆林县者浪乡坡合村(105°13′27″ E,24°44′58″ N)采集到5号两栖动物标本,经形态特征比较,与腹斑掌突蟾(Leptobrachella ventripunctata)相似;基于线粒体16S rRNA和12S rRNA基因片段构建的贝叶斯系统发育树显示,此次采集到的掌突蟾属标本与腹斑掌突蟾聚为一支,且具有较高的后验概率(1.00);基于Kimura双参数模型估算本次采集的标本与腹斑掌突蟾的遗传距离为0.7% ~ 0.9%,远小于掌突蟾属物种间的遗传距离(4.4% ~ 23.4%)。综合形态特征和系统发育分析比较,鉴定此次采集的掌突蟾属标本为腹斑掌突蟾,为广西两栖动物分布新记录种。  相似文献   

4.
由于栖息地质量下降,近年来齿突蟾属物种种群数量急剧减少,明确齿突蟾属物种空间分布,是监测、管理、保护齿突蟾属物种的基础。横断山区可能是齿突蟾属的起源中心和分化中心,但齿突蟾属在横断山区的地理分布格局尚不明确。利用优化后Maxent模型,首次预测西藏齿突蟾Scutiger boulengeri、刺胸齿突蟾Scutiger mammatus、胸腺齿突蟾Scutiger glandulatus、圆疣齿突蟾Scutiger tuberculatus、贡山齿突蟾Scutiger gongshanensis 5种高海拔齿突蟾属物种在横断山南生物多样性保护优先区域的潜在地理分布,并分析其与环境因子的关系。结果显示,5种齿突蟾属物种在横断山南的潜在地理分布格局存在差异,西藏齿突蟾主要分布在横断山南的北部,圆疣齿突蟾主要分布在横断山南东北部的四川省境内,贡山齿突蟾主要分布在横断山南的西南部,刺胸齿突蟾和胸腺齿突蟾的潜在分布格局较为相似,在横断山南的中部、西北部地区都有较多分布,但胸腺齿突蟾潜在分布区更为碎片化。另外,横断山南北部地区的齿突蟾属丰富度明显高于南部地区。环境变量贡献率和刀切法结果显示温度因子和降水因子是决定横断山南齿突蟾属潜在分布的主要因素,最冷季降水量对西藏齿突蟾、贡山齿突蟾、圆疣齿突蟾潜在分布有重要影响,但它们对最冷季降水量的偏好存在差异。此外,研究也显示,通过评估潜在的Maxent参数组合,选择最佳的Maxent模型是有效且必要的。  相似文献   

5.
曹燕  谢锋  江建平 《四川动物》2011,30(2):214-219,封3
观察了齿突蟾属Scutiger 2亚属、4物种[西藏齿突蟾S.(Scutiger) boulengeri、刺胸猫眼蟾S.(Aelurophryne) mammatus、木里猫眼蟾S.(A.) muliensis和胸腺猫眼蟾S.(A.) glandulatus]的体背、体腹皮肤及其腺体的组织形态学结构,结果表明:4个物种...  相似文献   

6.
根据形态特征比较,浙江丽水所采集的异角蟾标本应属一新种——丽水异角蟾Xenophrys lishuiensis Wang,LiuJiang,sp.nov.。正模标本:WYF00164,雄性成体,2016年5月20日采于浙江省丽水市莲都区葑垟林场附近(28°11′51.72″N,119°49′2.28″E,海拔1 100 m);配模标本:WYF00169,雌性成体;副模标本:12♂♂(WYF00165~WYF00168,WYF00171~WYF00178),2♀♀(WYF00170和WYF11011),均与正模同时、同地采集。正模和配模标本,以及8号副模标本(WYF00165~WYF00168,WYF00171~WYF00173,WYF11011)保存于中国科学院成都生物研究所两栖爬行动物标本馆,其余6号副模标本(WYF00170,WYF00174~WYF00178)保存于浙江自然博物馆。丽水异角蟾主要鉴别特征为:1)体型小,雄性体长30.7~34.7 mm,雌性体长36.9~40.4 mm;2)头长略大于头宽;3)无犁骨棱,无犁骨齿;4)舌游离端无缺刻;5)掌突2个;6)胫长不及体长之半;7)趾间无蹼,趾侧无缘膜;8)背部具"X"形斑块,或"X"形斑中间断开,色斑粗,边缘清晰且镶浅色边;9)头背三角形斑与体背斑块不相连;10)雄性肩部具不显著的浅色半圆斑;11)雄性第一、二指背面具婚垫和极小而密集的婚刺,第二指婚刺较少。依据线粒体基因16S r RNA共397 bp序列以贝叶斯法构建异角蟾属14个物种间的系统发育关系。包括新种丽水异角蟾在内的10个异角蟾属物种,以高支持率(后验概率98%)形成一个单系(支系B),其中,该种3个个体以高支持率(后验概率100%)形成一个单独的支系,与其近缘种淡肩异角蟾(X.boettgeri)之间的遗传距离为3.9%,大于同属部分物种间遗传距离。  相似文献   

7.
2023年6月12日,在湖南省城步县南山国家公园(110°11′42″E,26°11′54″N)采集到无尾目(Anura)角蟾科(Megophryidae)布角蟾属(Boulenophrys)雌性标本1号(标本号NS20230612),现保存于湖南师范大学生命科学学院脊椎动物学实验室。该标本背部皮肤光滑有痣粒,两侧皮肤松弛,有刺疣,背部灰褐色,背中央有深色“X”形斑,与花坪角蟾(B. mirabilis)形态鉴别特征一致。基于线粒体16Sr RNA和COI基因片段进行的系统发育分析结果显示,该标本与花坪角蟾聚为一支;平均遗传距离为0.28%,远小于布角蟾属物种间的遗传距离。结合形态特征比较与系统发育关系重建,鉴定该标本为角蟾科布角蟾属花坪角蟾,查阅相关文献资料,确认花坪角蟾为湖南省两栖纲分布新记录种。该物种的发现丰富了南山国家公园的两栖爬行动物物种多样性,同时为该物种分类及谱系地理学研究提供了参考资料。  相似文献   

8.
费梁  叶昌媛 《动物学研究》1989,10(4):295-302
本文在探讨亚洲高海拔锄足蟾的属间分类的基础上,进一步对其齿蟾属Oreolalax和齿突蟾属Scutiger所隶的齿突蟾亚属Scutiger(Scutiger)、猫眼蟾亚属Scutiger(Aelurophryne),共计29种的地理分布及其特点作了概括性的综述;并探讨了他们的起源和演化途径;横断山系地区可能是它们的主要分化中心和物种形成中心。  相似文献   

9.
云南省发现弄岗狭口蛙   总被引:1,自引:0,他引:1  
2018年6月,在位于云南省文山壮族苗族自治州的文山国家级自然保护区(23°21′41″N,104°50′26″E,海拔1 300 m)采集到无尾目(Anura)姬蛙科(Microhylidae)狭口蛙属(Kaloula)标本3号,包括雄性成体标本1号和雌性成体标本2号,并对相应形态特征进行了测量,雄性头体长为35.79mm,雌性头体长为48.01 mm和42.78 mm。根据形态特征比较发现,该种群的标本皮肤光滑,背部呈橄榄绿色,有不规则的深绿色斑纹,指端平切且具两排小乳突,雄性胸部有小柠檬黄色斑点,雄性全蹼,雌性为1/3蹼,与采集自弄岗国家级自然保护区的弄岗狭口蛙(K. nonggangensis)地模标本(海拔186 m)的形态鉴定特征基本一致,仅体色和体型大小稍有差异。基于16S rRNA基因片段进行系统发育分析表明,这些标本与弄岗狭口蛙模式产地标本聚在一起,共享同一单倍型。可以确定所采集的3号标本均为弄岗狭口蛙,为云南省两栖纲分布新记录物种。新发现的种群分布于中高海拔处,较地模标本的低海拔分布记录有较大的拓展。该物种的发现说明,云南东南部与广西西南部的喀斯特地区具有相似的物种组成,对该区域将来的生物地理学研究具有重要意义。  相似文献   

10.
2019至2023年,在四川省珙县(104°50′05″E,27°54′27″N,海拔1 331 m)和叙永县(105°32′05″E,28°13′51″N,海拔1370m)分别采集到2号和4号绒鼠类成体标本。这些标本个体较小,尾长约为体长的41%,形态鉴定属于滇绒鼠(Eothenomys eleusis)。对所采标本的Cyt b基因进行PCR扩增和测序,并结合从GenBank下载的绒鼠属物种序列构建贝叶斯基因树,结果显示:所采标本与滇绒鼠指名亚种(E. e. eleusis)聚为一个支系(贝叶斯后验概率为1.0),遗传距离为0.8%,与滇绒鼠aurora亚种(E.e.aurora)的遗传距离为2.5%。根据标本形态、头骨特征,结合分子生物学证据,确定所采6号标本为滇绒鼠,是该物种在四川省的首次确认分布记录。标本现存于四川省林业科学研究院动物标本馆(编号分别为SAF19843、SAF19844、SAF220125、SAF220131、SAF23176和SAF23177)。  相似文献   

11.
Plant regeneration from mesophyll protoplasts of pepper,Capsicum annuum L. cv. California Wonder has been demonstrated via shoot organogenesis. Protoplasts isolated from fully expanded leaves of 3-week-old axenic shoots when cultured in TM medium supplemented with 1 mg l −1 NAA, 1 mg l −1 2,4-D, 0 5 mg l −1 BAP (CM 1) resulted in divisions with a frequency ranging from 20–25 %. Antioxidant ascorbic acid and polyvinylpyrrolidone (PVP) in the medium and incubation in the dark helped overcome browning of protoplasts. Microcalli and macrocalli were formed in TM medium containing 2 mg l −1 NAA and 0.5 mg l −1 BAP (CM II) and MS gelled medium containing 2 mg 1 −1 NAA and 0 5 mg 1 −1 BAP (CM III), respectively. Regeneration of plantlets was possible via caulogenesis. Microshoots, 2–5 percallus appeared on MS gelled medium enriched with 0.5 mg l −1 IAA, 2mg l −1 GA and l0mg l −1 BAP (CM IVc). Rooting of microshoots was obtained on half strength gelled medium containing 1 mg l −1 NAA and 0.5mg l −1 BAP. Protoplasts isolated from cotyledons failed to divide and degenerated eventually.  相似文献   

12.
We describe the new genus Elektrothopomyia n. gen., with two new species E. saltensis n. sp. and E. tzotzili n. sp. as second and third fossil Pachygastrinae from the Mexican amber. These fossils from the Totolapa amber deposit confirm the presence of this group in Central America during the late Oligocene to middle Miocene period. Their exact affinities remain uncertain because of the current problems in the phylogenetic classification of these flies. These fossils are new elements of comparison between the entomofaunas of the Dominican and Mexican amber.  相似文献   

13.
DNA vaccination has proved to be a generally applicable technology in various preclinical animal models of infectious and noninfectious disease and several DNA vaccines have now entered phase I human clinical trials. It is too early to predict the effectiveness of DNA vaccines in humans and whether improved formulations of DNA vaccines will be required but several lines of investigation have suggested ways in which DNA vaccines may be improved, such as increases in expession, facilitation of DNA targeting or uptake, and enhancement of immune responses.  相似文献   

14.
中国大鲵(Andrias davidianus)是世界上最大的两栖动物,曾在中国广泛分布。前期的3项分子遗传学研究表明:黄山的中国大鲵种群存在独特的遗传分化,是一个未被描述的物种。这3项研究中的分子数据均基于本文通讯作者1995年之前采自中国安徽省黄山市祁门县的原生大鲵标本。本文基于形态学比较,将1995年以前本文通讯作者在祁门县采集的11个大鲵标本描述为大鲵属一新种:祁门大鲵(Andrias cheni sp. nov.)。我们测量了11个标本的25个形态特征,并与大鲵属的其他物种进行比较。祁门大鲵与大鲵属其他物种可通过以下特征进行区分:(1)头躯扁平,头长略大于头宽,头宽/头长(HW/HL)比为0.80 ~ 0.98;(2)头部和下颌相对光滑,有不规则排列的小结节;(3)颈部侧褶与体褶不连续;(4)第三指比第一指长,指式Ⅰ< Ⅳ < Ⅲ < Ⅱ;(5)四肢粗而短,后肢比前肢长,前肢长/后肢长(FLL/PLL)比为0.78 ~ 0.96;(6)尾部肌肉发达,基部粗大,后部和上部逐渐变平,尾长约为总长度的1/3。经形态比较,本研究将祁门大鲵描述为新种,大鲵属物种增加到5个。本文提供了相对完备的形态数据,可为后续大鲵野生谱系的资源保护、人工种群遗传管理和增殖放流等提供参考。  相似文献   

15.
16.
Many behavioural aspects of Anoplius infuscatus (Vander Linden) and Episyron sp. Schioedte were examined in detail, both on a qualitative and, when possible, on a quantitative level, during a long-term field study in Northern Italy. Both wasps dig unicellular nests on bare soil, which are filled with a single spider to feed the brood. The main differences regard the way to hunt their prey, that of burrowing, that of transporting and introducing the spider into the nest, the habit of amputating spider legs and the abdominal movements during nest closing. On the whole, starting from prey capture to nest closure, A. infuscatus is significantly slower than Episyron. The observed ethological differences are well fitted to the exploitation of the different preys consisting in wolf spiders (Lycosidae) and orb weaving spiders (Araneidae), respectively. Some flexibility in the observed behaviour is described. A critical re-examination of the literature shows that, even if most results agree with those of previous authors, two controversial points remain open regarding Episyron species: the position of the egg (on the prey or on the cell wall) and the way to grasp the spider during tranport and introdution into the nest.  相似文献   

17.
Extracellular signals are transduced across the cell by the cell surface receptors, with the aid of G-proteins, which act at a critical point of signal transduction and cellular regulation. Structurally, G-proteins are heterotrimeric consisting α, β and γ subunits but in functionally active state they dissociate into α subunit coupled to GTP and as βγ dimer. G-proteins can be broadly divided into two classes based on their sensitivity to pertussis toxin and cholera toxin. Existence of various forms of each of the subunit allows molecular diversity in the subunit species of G-proteins. These subunits interact with a wide range of receptors and effectors, facilitated by post translational modification of their subunits. Different types of G-proteins mediate several signalling events in different parts of the body. This review summarizes the features of (i) structural and functional heterogenity among different subunits of G-proteins, (ii) interaction of G-proteins and their subunits with effectors with specific cases of G-protein mediated signalling in olfaction, phototransduction in the retina, ras andras related transduction and (iii) disease conditions associated with malfunctioning of G-proteins.  相似文献   

18.
Two yolk proteins (YP1 and YP2) from the ovaries of Indian major carp, Labeo rohita were isolated by gel filtration and partially characterized by the use of hydroxyapatite ultrogel column in conjunction with native PAGE. On native PAGE YP1 gave a single protein band, whereas YP2 of gel filtration revealed the contamination of YP1, which was removed by adsorption chromatography on hydroxyapatite ultrogel and then the YP2 was the purified one as judged by electrophoresis. Both YP1 and YP2 also stained for lipid and contained alkalilabile phosphorus. Therefore, both yolk proteins were lipophosphoprotein. The molecular weights of YP1 and YP2 were 620 kDa and 225 kDa respectively as determined by gel filtration on Sepharose 4B. When YP1 and YP2 were compared in relation to some physicochemical characteristics with yolk proteins of other oviparous vertebrates including fish, they were lipovitellin like. Antiserum to YP2 crossreacted with YP2 and vitellogenin suggesting that YP2 was the cleaved product of vitellogenin. Anti-YP2 antiserum was not crossreacted with native YP1, whereas reduced and/or denatured YP1 was crossreacted indicating the presence of antigenic determinants in the inner core region of YP1 polypeptide.  相似文献   

19.
Some murine (YAC, P815 and SP20) and human (Molt4, Raji and HR7) tumour cell lines were (i) treated with IFN-γ for inducing enhanced expression of MHC class I antigen, or (ii) given a brief treatment with citrate buffer (pH 3.0), which resulted in denaturation of class I MHC antigens on these tumour cells. IFL-γ or acid treated tumour cells were used as unlabelled competing targets in cold target inhibition assays. The results indicated that the competing ability of acid-treated tumour cells remained unaltered, whereas IFN-γ treated tumour cells competed with significantly less efficiency. These results have been evaluated in light of the current view of NK cell development and the expression of inhibitory receptors for MHC class I molecules (IRMs), on NK cells. A modified view on NK cell heterogeneity based upon IRM expression has been proposed which reconciles several apparently discordant observations about the activity and role of NK cells. Two classes of NK cells have been proposed. Type I NK ceils have target recognition receptors which do not recognize autologous normal cells, lack IRMs, and may participate in first line of defence against transformed cells in vivo. Type II NK cells have target recognition receptors for autologous normal cells and express at least one self-reactive IRM in order to prevent auto-killing. Type II NK cells participate in killing those transformed cells which down-regulate their MHC class I expression in order to escape cytotoxic T-cell surveillance. It is also postulated that mechanism of inverse correlation of target cell MHC class I expression levels and their susceptibility to NK cells, involves interference model of missing self hypothesis for type I NK cells and inhibitory signal model of missing self hypothesis for type II NE cells. Finally, it is proposed that acid treatment of tumour cells enhances their lysis susceptibility by making them additionally susceptible to type II NK cells, rather than enhancing their killing by type I NK cells. This proposition would explain the lack of effect of acid treatment on the competing ability of tumour cells, when target cells are only lysed by type I NE cells.  相似文献   

20.
Amino acid sequences of proteinaceous proteinase inhibitors have been extensively analysed for deriving information regarding the molecular evolution and functional relationship of these proteins. These sequences have been grouped into several well defined families. It was found that the phylogeny constructed with the sequences corresponding to the exposed loop responsible for inhibition has several branches that resemble those obtained from comparisons using the entire sequence. The major branches of the unrooted tree corresponded to the families to which the inhibitors belonged. Further branching is related to the enzyme specificity of the inhibitor. Examination of the active site loop sequences of trypsin inhibitors revealed that here are strong preferences for specific amino acids at different positions of the loop. These preferences are inhibitor class specific. Inhibitors active against more than one enzyme occur within a class and confirm to class specific sequence in their loops. Hence, only a few positions in the loop seem to determine the specificity. The ability to inhibit the same enzyme by inhibitors that belong to different classes appears to be a result of convergent evolution.  相似文献   

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