沙蜥属Phrynocephalus生物地理学研究进展

沙蜥属Phrynocephalus作为鬣蜥科Agamidae中的古北界类群,分布区复杂的地质、地理历史对该属物种形成、分化及分布格局的形成具有重要的影响.近年来,随着生物地理学理论的不断发展,各国学者从不同角度对沙蜥属的生物地理学做了大量研究.本文主要综述了这方面的研究进展;同时基于沙蜥属的研究现状对今后的研究做出展望.     

九种沙蜥的核型——兼论中国沙蜥属核型演化

报道了沙蜥属９种２１个不同居群的核型及银分带核型。荒漠沙蜥、草原沙蜥和斑点沙蜥２ｎ＝４６＝２２Ｉ＋２４ｍ,ＮＦ＝４６。叶城沙蜥２ｎ＝４６＝２ｓＩ＋２０Ｉ＋２４ｍ,ＮＦ＝４６。南疆沙蜥、泽当沙蜥、青海沙蜥和红原沙蜥２ｎ＝４８＝２４Ｉ＋２４ｍ,ＮＦ＝４８。青海沙蜥具有异型性染色体。大耳沙蜥２ｎ＝４８＝２Ｖ＋８ｓＶ＋１２ｓＩ＋２６ｍ,ＮＦ＝５８。９种中,ＮＯＲ均位于微小染色体对上。与本属已知核型比较,确认我国沙蜥属核型均来自共同的核型祖先,可分为３个核型类群：（１）２ｎ＝４６,１１对大染色体类群;（２）２ｎ＝４８,１２对大染色体类群;（３）大耳沙蜥。前两个类群核型与生态地理分布紧密相关。讨论了我国沙蜥属物种核型演化趋势,并结合地史资料探讨了本属核型演化与第三纪以来古地史变迁的关系。     

西藏沙蜥属一新种—泽当沙蜥

根据形态特征,泽当居群与西藏沙蜥、红尾沙蜥有显著区别,为沙蜥属一新种：泽当沙蜥Ｐｈｒｙｎｏｃｅｐｈａｌｕｓ ｚｅｔａｎｇｅｎｓｉｓ ｓｐ．ｎｏｖ．Ｗａｎｇ,Ｚｅｎｇ ｅｔ Ｗｕ鉴别特征为鼻鳞１枚;鼻间鳞４－５枚;背鳞数少于腹鳞数;雄性尾末端黑色,雌性灰白色。     

中国的沙蜥属研究

本文对我国迄今所知的１８种沙蜥,进行了生物学特性,地理成分和分布的叙述,并依据其开矿特征分别编制民成,幼体的种类检索表,供分类以及野外采集和生态研究时鉴定蜥种使用。     

沙蜥属一有效种贵德沙蜥及红原沙蜥的分类研究(蜥蜴亚目:鬣蜥科)

形态,染色体特征聚类分析表明过去归入青海沙蜥的天祝,贵德居群被聚为一支,而青海沙蜥的其它居群和红原沙蜥 聚为另一支,证明贵,在祝居群与青海沙蜥有显著区别,应当恢复贵德沙蜥Phrynocephalus putjatia为有效种。贵德沙蜥与青海沙蜥的主要鉴别特重是前者的尾长大于吻肛长,后者的尾短,小于吻肛长,前者背鳞100枚以上,后者背鳞不到100枚。红原沙蜥Phrynocephalus hongyuanensis与青海沙蜥的染色体和形态特征相似,应归隶青海沙蜥。     

锦鸡儿属分析生物地理学的研究

将锦鸡儿属（Ｃａｒａｇａｎａ）植物分布区划分成１３个。在分支系统学基础上,进行了分布区的万分分析。以种类和系为分布特征,进行分布区的聚类分析和最小生成树分析。分布区分支图、表征图和最小生成树从不同方面表达了分布区的关系。锦鸡儿属的分布区被分成东亚和古地中海两大部分。其中分别来自这两部分的前苏联远东－我国东北与阿尔泰－萨彦岭分布区有密切关系。基于分布区分支图,属的分布区分别由这两个部分分布区衍生,同     

水杉属研究述评

水杉属研究述评刘艳菊李承森王宇飞（中国科学院植物研究所,北京１０００９３）ＲｅｖｉｅｗｏｎＧｅｎｕｓＭｅｔａｓｅｑｕｏｉａＬｉｕＹａｎ－ＪｕＬｉＣｈｅｎｇ－ＳｅｎＷａｎｇＹｕ－Ｆｅｉ（ＩｎｓｔｉｔｕｔｅｏｆＢｏｔａｎｙ,ＡｃａｄｅｍｉａＳｉｎｉｃａ...     

三种沙蜥核型的比较研究

本文报道了白条沙蜥Ｐｈｒｙｎｏｃｅｐｈａｌｕｓ ａｌｂｏｌｉｎｅａｔｕｓ,东疆沙蜥Ｐ．ｇｒｕｍｇｒｉｚｉｍａｌｏｉ及西藏沙蜥Ｐ．ｔｈｅｏｂａｌｄｉ的核型,西藏沙蜥２ｎ＝２２Ｉ＋２６ｍ,ＮＦ＝４８,其余二者２ｎ＝２２Ｉ＋２４ｍ,ＮＦ＝４６。与同属已知其它的核型进行了比较。沙蜥属中至少存在２ｂ＝４６和２ｎ＝４８两种核型类群,二者可能与“沙蜥属物种形成的两个起源中心”的假说相关。讨论了沙蜥属中的核型演化     

雪松属的细胞分类学及历史植物地理学研究

雪松属含雪松,北非雪松、黎巴嫩雪松和短叶雪松等４种,它们间断分布于西北喜马拉雅、西北非及西亚。本文分析了雪松的核型,Ｋ（２ｎ）＝２４＝１８ｍ＋６ｓｍ,该结果与Ｈｉｚｕｍｅ（１９８８）的一致但不同于Ｍｅｈｒａ＆Ｋｈｏｓｈｏｏ（１９５６）的。作者比较了雪松属３个代表种的核型并提出了它们的进化趋势可能是雪松→北非雪松→黎巴嫩雪松。从松科各属核型的比较分析,作者认为将雪松属由落叶松亚科分出置于冷杉亚科是合乎需要的。根据细胞学、化石、地理分布、古地理和古气候等资料,本文还讨论了雪松属的起源、迁移和进化。     

荒漠沙蜥食物的两性差异

对2008年4～6月在甘肃省甘塘、阿拉善左旗、民勤、山丹采集的荒漠沙蜥样本进行了食物两性差异的研究。主要采用剖胃法对219个荒漠沙蜥胃样的6021个食物做了识别和鉴定。结果表明,荒漠沙蜥的食性为动物性,食物多为昆虫,主要取食半翅目和膜翅目昆虫,尤其是长蝽科和蚁科(合计高于70%),取食猎物的体积大小集中在0.01～20mm3。4个种群的沙蜥对长蝽科昆虫均表现为正向选择,部分种群对蚁科昆虫表现负向选择。可能是因为沙蜥有食物选择性,对长蝽科昆虫取食较多,对拟步甲科摄食较少。较多地取食蚂蚁则是因为生境中喜好食物较少,而蚁科昆虫数量多,遇见率也较高。荒漠沙蜥雌雄个体食物生态位重叠度极高,但是卡方检验的结果却表明两性在食物组成和食物大小存在显著差异。由于雌雄个体对同种食物有相同的选择性,因此导致两性在食物组成和食物大小上存在显著差异的原因可能是雄性家域范围更大,对食物有更多选择。     

奇台沙蜥生长过程中的两性异形

研究奇台沙蜥Phrynocephalus grumgrzimailoi头、尾、腋胯距大小在个体发育过程中的变化.成体体长(SVL)无显著的两性差异,两性异形主要表现为雄性个体有较大的头部(头长和头宽)和尾部,雌性具有较大的腋胯距.头、尾、腋胯距大小的两性异形在幼体就已存在,并随个体发育的进行变得更加显著.不同年龄组两性个体头部、尾部、腋胯距随SVL呈异速增长,表现为两性头部的增长速率在个体发育过程中逐渐增大,尾部的增长速率逐渐减慢,腋胯距在雌性蜥蜴中增长速率逐渐增大,在雄性中逐渐变小.     

A phylogeny of Chinese species in the genus Phrynocephalus (Agamidae) inferred from mitochondrial DNA sequences

We investigated the phylogenetic relationships among most Chinese species of lizards in the genus Phrynocephalus (118 individuals collected from 56 populations of 14 well-defined species and several unidentified specimens) using four mitochondrial gene fragments (12S rRNA, 16S rRNA, cytochrome b, and ND4-tRNA(LEU)). The partition-homogeneity tests indicated that the combined dataset was homogeneous, and maximum-parsimony (MP), neighbor-joining (NJ), maximum-likelihood (ML) and Bayesian (BI) analyses were performed on this combined dataset (49 haplotypes including outgroups for 2058bp in total). The maximum-parsimony analysis resulted in 24 equally parsimonious trees, and their strict consensus tree shows that there are two major clades representing the Chinese Phrynocephalus species: the viviparous group (Clade A) and the oviparous group (Clade B). The trees derived from Bayesian, ML, and NJ analyses were topologically identical to the MP analysis except for the position of P. mystaceus. All analyses left the nodes for the oviparous group, the most basal clade within the oviparous group, and P. mystaceus unresolved. The phylogenies further suggest that the monophyly of the viviparous species may have resulted from vicariance, while recent dispersal may have been important in generating the pattern of variation among the oviparous species.     

Cladogenesis and phylogeography of the lizard Phrynocephalus vlangalii (Agamidae) on the Tibetan plateau

Phrynocephalus vlangalii is restricted to dry sand or Gobi desert highlands between major mountain ranges in the Qinghai (Tibetan) Plateau. Mitochondrial DNA (mtDNA) sequence (partial ND2, tRNA(Trp) and partial tRNA(Ala)) was obtained from 293 Phrynocephalus sampled from 34 sites across the plateau. Partitioned Bayesian and maximum parsimony phylogenetic analyses revealed that P. vlangalii and two other proposed species (P. erythrus and P. putjatia) together form a monophyletic mtDNA clade which, in contrast with previous studies, does not include P. theobaldi and P. zetangensis. The main P. vlangalli clade comprises seven well-supported lineages that correspond to distinct geographical areas with little or no overlap, and share a most recent common ancestor at 5.06 +/- 0.68 million years ago (mya). This is much older than intraspecific lineages in other Tibetan animal groups. Analyses of molecular variance indicated that most of the observed genetic variation occurred among populations/regions implying long-term interruption of maternal gene flow. A combined approach based on tests of population expansion, estimation of node dates, and significance tests on clade areas indicated that phylogeographical structuring has been primarily shaped by three main periods of plateau uplift during the Pliocene and Pleistocene, specifically 3.4 mya, 2.5 mya and 1.7 mya. These periods corresponded to the appearance of several mountain ranges that formed physical barriers between lineages. Populations from the Qaidam Basin are shown to have undergone major demographic and range expansions in the early Pleistocene, consistent with colonization of areas previously covered by the huge Qaidam palaeolake, which desiccated at this time. The study represents one of the most detailed phylogeographical analyses of the Qinghai Plateau to date and shows how geological events have shaped current patterns of diversity.     

Grooming behaviours in the Hymenoptera (Insecta): potential phylogenetic significance

Grooming behaviours from representatives of 36 families of Hymenoptera were video recorded and analysed. Thirty-three distinct types of grooming movements were recognized. The evolutionary pattern of each behaviour is discussed. Some behaviours displayed consistent variation between taxa, and appear to be informative regarding higher level relationships within the order. Putative synapomorphies are reported that support the monophyly of the Apocrita, Cynipoidea, Platygastroidea, Ichneumonoidea, and Chalcidoidea including the Mymaridae.     

Diet,Food Intake of Phrynocephalus frontalis （Agamidae） and Its Potential Role in Desert Habitat

We examined the dietary diversity and food intake of Phrynocephalus frontalis, compared the difference of insect diversity in the natural habitats with different lizard densities, and discussed the potential role of this lizard in the desert ecosystem. The results show that： （1） arthropodans of the orders Coleoptera, Hymenoptera and Hemiptera were major dietary components of P. frontalis; （2） coleoptera larvae always formed the predominant component of lizard diets; （3） dietary diversities of P. frontalis were not significantly different between summer and autumn or between the two sexes; （4） the similarity in trophic niches between seasons was 0.756, whereas the similarity in trophic niches between sexes was 0.994; （5） stomach content weight of lizards varied significantly among different seasons, but there was no significant difference in stomach content weight between sexes; （6） insect diversity differed significantly among the groups of the habitat with different degrees of lizard density, and the habitat with moderate lizards density had the highest insect diversity. We infer that P. frontalis prey mainly on insects and change their diet and food intake with season; males and females consumed similar preys in types and weights. As an important predator, P. frontalis could affect the insect community in the arid ecosystem of Hunshandak Desert on the Mongolian Plateau.