共查询到20条相似文献,搜索用时 46 毫秒
1.
2.
两栖爬行动物是良好的环境指示类群,容易受到环境变化的影响,目前正经历着全球范围的种群快速下降和物种灭绝。最新的《中国脊椎动物红色名录》评估发现, 37.05%的两栖动物和30.5%的爬行动物受到威胁。开展国家级科学监测,研究和分析两栖爬行动物多样性变迁及其驱动因素是保护的前提。作为中国生物多样性监测与研究网络的重要组成部分,两栖爬行动物监测与研究专项网通过对11个典型样区中两栖爬行动物的组成、种群动态和结构进行长期监测和研究,将野外数据与生态模型相结合,探讨两栖爬行动物的种群现状、群落结构及其动态,以及针对我国两栖爬行动物应对未来环境变化提出及时有效的保护管理对策。在两栖爬行动物多样性研究、极危两栖动物中国大鲵(Andrias davidianus)和濒危两栖动物大凉螈(Liangshantriton taliangensis)的保护、环境DNA (eDNA)技术和无线电追踪技术开拓与应用、荒漠化生境对爬行动物的生态影响、外来入侵种的扩展机制等方面取得了重要进展,明显提升了中国两栖爬行动物监测能力和研究水平。未来尚需持续加大监测网络建设,普及先进监测技术,从法律法规层面强调两栖爬行动物... 相似文献
3.
4.
广西百东河自然保护区两栖爬行动物资源调查 总被引:2,自引:1,他引:1
2004年4月~2006年6月对广西百东河自然保护区两栖爬行动物资源进行了调查,结果表明:百东河自然保护区现已记录51种两栖爬行动物,其中两栖类1目5科8属17种;爬行类2目11科25属34种。对保护区两栖爬行动物区系及资源现状进行了评价。 相似文献
5.
6.
7.
2004年7月20日~8月20日由沈阳师范大学资助、赵尔宓院士组织领导,李丕鹏教授任总领队,由全国9个单位的13位专业技术人员组成的“IUCN——中国两栖爬行动物专家组2004——西藏考察队”,分别对藏北、墨脱、藏东地区进行了科学考察,此次考察活动也是自1973年以来对西藏地区两栖爬行动物范围最广、规模最大的一次科学考察。 相似文献
8.
江西南矶山自然保护区两栖爬行动物资源调查与评价 总被引:7,自引:4,他引:3
2004年6月上旬和8月下旬两次对位于鄱阳湖主湖南部的江西南矶山省级自然保护区两栖爬行动物资源进行了实地考察.调查表明:南矶山自然保护区现已记录31种两栖爬行动物,隶属2纲4目13科.其中两栖纲1目5科11种;爬行纲3目8科20种.其动物区系组成以东洋界种类明显占优势,占总物种数的67.65%.两栖爬行动物地理区划属东洋界华中区东部丘陵平原亚区赣北(鄱阳湖)平原省,此次调查发现的斑腿泛树蛙和舟山眼镜蛇为该动物地理省的新分布记录.最后对保护区两栖爬行动物资源现状进行了评价,并提出了保护和管理建议. 相似文献
9.
10.
为掌握贺兰山两栖爬行动物物种多样性及区系特征,于2007-2008年,采用样带调查法对贺兰山两栖爬行动物进行了系统调查。结果表明:贺兰山两栖爬行动物共计2目8科12属19种,其中王锦蛇(Elaphe carinata)和玉斑锦蛇(E.mandarina)为宁夏爬行动物新纪录种;贺兰山两栖爬行动物Shannon多样性指数为2.250,均匀性指数为0.563,其两栖爬行动物科数和种数分别占宁夏两栖爬行动物总科数和种数的72.7%和67.9%,分别占内蒙古两栖爬行动物总科数和种数的66.7%和50.0%;花背蟾蜍(Bufo raddei)、中国林蛙(Rana chensinensis)、荒漠沙蜥(Phrynocephalus przewalskii)、草原沙蜥(P.frontalis)、丽斑麻蜥(Eremias argus)和密点麻蜥(E.multiocellata)是贺兰山优势种,花条蛇(Psammophis lineo-latus)、黄脊游蛇(Coluber spinalis)和虎斑颈槽蛇(Rhabdophis tigrinus)为常见种,其余种类为偶见种;贺兰山两栖爬行动物物种中,14种为古北界物种,5种为广布种,且蒙新区物种成分优势明显,占42.6%,反映了贺兰山两栖爬行动物具有典型的蒙新区西部荒漠亚区的物种组成和区系特征。 相似文献
11.
12.
13.
14.
On the origin of the Hirudinea and the demise of the Oligochaeta 总被引:10,自引:0,他引:10
Martin P 《Proceedings. Biological sciences / The Royal Society》2001,268(1471):1089-1098
The phylogenetic relationships of the Clitellata were investigated with a data set of published and new complete 18S rRNA gene sequences of 51 species representing 41 families. Sequences were aligned on the basis of a secondary structure model and analysed with maximum parsimony and maximum likelihood. In contrast to the latter method, parsimony did not recover the monophyly of Clitellata. However, a close scrutiny of the data suggested a spurious attraction between some polychaetes and clitellates. As a rule, molecular trees are closely aligned with morphology-based phylogenies. Acanthobdellida and Euhirudinea were reconciled in their traditional Hirudinea clade and were included in the Oligochaeta with the Branchiobdellida via the Lumbriculidae as a possible link between the two assemblages. While the 18S gene yielded a meaningful historical signal for determining relationships within clitellates, the exact position of Hirudinea and Branchiobdellida within oligochaetes remained unresolved. The lack of phylogenetic signal is interpreted as evidence for a rapid radiation of these taxa. The placement of Clitellata within the Polychaeta remained unresolved. The biological reality of polytomies within annelids is suggested and supports the hypothesis of an extremely ancient radiation of polychaetes and emergence of clitellates. 相似文献
15.
16.
17.
18.
19.
Göran Malmberg 《Systematic parasitology》1990,17(1):1-65
Data on the ontogeny of the posterior haptor of monogeneans were obtained from more than 150 publications and summarised. These data were plotted into diagrams showing evolutionary capacity levels based on the theory of a progressive evolution of marginal hooks, anchors and other attachment components of the posterior haptor in the Monogenea (Malmberg, 1986). 5 + 5 unhinged marginal hooks are assumed to be the most primitive monogenean haptoral condition. Thus the diagrams were founded on a 5 + 5 unhinged marginal hook evolutionary capacity level, and the evolutionary capacity levels of anchors and other haptoral attachement components were arranged according to haptoral ontogenetical sequences. In the final plotting diagram data on hosts, type of spermatozoa, oncomiracidial ciliation, sensilla pattern and protonephridial systems were also included. In this way a number of correlations were revealed. Thus, for example, the number of 5 + 5 marginal hooks correlates with the most primitive monogenean type of spermatozoon and with few sensillae, many ciliated cells and a simple protonephridial system in the oncomiracidium. On the basis of the reviewed data it is concluded that the ancient monogeneans with 5 + 5 unhinged marginal hooks were divided into two main lines, one retaining unhinged marginal hooks and the other evolving hinged marginal hooks. Both main lines have recent representatives at different marginal hook evolutionary capacity levels, i.e. monogeneans retaining a haptor with only marginal hooks. For the main line with hinged marginal hooks the name Articulon-choinea n. subclass is proposed. Members with 8 + 8 hinged marginal hooks only are here called Proanchorea n. superord. Monogeneans with unhinged marginal hooks only are here called Ananchorea n. superord. and three new families are erected for its recent members: Anonchohapteridae n. fam., Acolpentronidae n. fam. and Anacanthoridae n. fam. (with 7 + 7, 8 + 8 and 9 + 9 unhinged marginal hooks, respectively). Except for the families of Articulonchoinea (e.g. Acanthocotylidae, Gyrodactylidae, Tetraonchoididae) Bychowsky's (1957) division of the Monogenea into the Oligonchoinea and Polyonchoinea fits the proposed scheme, i.e. monogeneans with unhinged marginal hooks form one old group, the Oligonchoinea, which have 5 + 5 unhinged marginal hooks, and the other group form the Polyonchoinea, which (with the exception of the Hexabothriidae) has a greater number (7 + 7, 8 + 8 or 9 + 9) of unhinged marginal hooks. It is proposed that both these names, Oligonchoinea (sensu mihi) and Polyonchoinea (sensu mihi), will be retained on one side and Articulonchoinea placed on the other side, which reflects the early monogenean evolution. Except for the members of Ananchorea [Polyonchoinea], all members of the Oligonchoinea and Polyonchoinea have anchors, which imply that they are further evolved, i.e. have passed the 5 + 5 marginal hook evolutionary capacity level (Malmberg, 1986). There are two main types of anchors in the Monogenea: haptoral anchors, with anlages appearing in the haptor, and peduncular anchors, with anlages in the peduncle. There are two types of haptoral anchors: peripheral haptoral anchors, ontogenetically the oldest, and central haptoral anchors. Peduncular anchors, in turn, are ontogenetically younger than peripheral haptoral anchors. There may be two pairs of peduncular anchors: medial peduncular anchors, ontogentically the oldest, and lateral peduncular anchors. Only peduncular (not haptoral) anchors have anchor bars. Monogeneans with haptoral anchors are here called Mediohaptanchorea n. superord. and Laterohaptanchorea n. superord. or haptanchoreans. All oligonchoineans and the oldest polyonchoineans are haptanchoreans. Certain members of Calceostomatidae [Polyonchoinea] are the only monogeneans with both (peripheral) haptoral and peduncular anchors (one pair). These monogeneans are here called Mixanchorea n. superord. Polyonchoineans with peduncular anchors and unhinged marginal hooks are here called the Pedunculanchorea n. superord. The most primitive pedunculanchoreans have only one pair of peduncular anchors with an anchor bar, while the most advanced have both medial and lateral peduncular anchors; each pair having an anchor bar. Certain families of the Articulonchoinea, the Anchorea n. superord., also have peduncular anchors (parallel evolution): only one family, the Sundanonchidae n. fam., has both medial and lateral peduncular anchors, each anchor pair with an anchor bar. Evolutionary lines from different monogenean evolutionary capacity levels are discussed and a new system of classification for the Monogenea is proposed.In agreeing to publish this article, I recognise that its contents are controversial and contrary to generally accepted views on monogenean systematics and evolution. I have anticipated a reaction to the article by inviting senior workers in the field to comment upon it: their views will be reported in a future issue of this journal. EditorIn agreeing to publish this article, I recognise that its contents are controversial and contrary to generally accepted views on monogenean systematics and evolution. I have anticipated a reaction to the article by inviting senior workers in the field to comment upon it: their views will be reported in a future issue of this journal. Editor 相似文献