135 resultados para REPTILIA


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Glaphyromorphus clandestinus, sp. nov., is described from granite-slab habitat on Mt Elliot, north-eastern Queensland. This species can be distinguished from its congeners by a combination of the following characters: large size (SVL 72 mm), adpressed limbs of adult separated by noticeably more than the length of the forelimb, 26 mid-body scale rows, and flanks patterned with dark flecks forming a series of longitudinal lines. The distribution, habitat preferences and habits of this species are poorly known. Currently G. clandestinus is known from a single locality where individuals have been found in an exposed area of exfoliating granite, set in a mosaic of rainforest and eucalyptus woodland. The discovery of this species brings to three the number of vertebrate species known to be endemic to Mt Elliot and highlights the evolutionary significance of this southerly outlier to the mountainous rainforest of the Wet Tropics.

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In the late 19th Century, the choanae (or internal nares) of the Plesiosauria were identified as a pair of palatal openings located rostral to the external nares, implying a rostrally directed respiratory duct and air path inside the rostrum. Despite obvious functional shortcomings, this idea was firmly established in the scientific literature by the first decade of the 20th Century. The functional consequences of this morphology were only re-examined by the end of the 20th Century, leading to the conclusion that the choanae were not involved in respiration but instead in underwater olfaction, the animals supposedly breathing with the mouth agape. Re-evaluation of the palatal and internal cranial anatomy of the Plesiosauria reveals that the traditional identification of the choanae as a pair of fenestrae situated rostral to the external nares appears erroneous. These openings more likely represent the bony apertures of ducts that lead to internal salt glands situated inside the maxillary rostrum. The 'real' functional choanae (or caudal interpterygoid vacuities), are situated at the caudal end of the bony palate between the sub-temporal fossae, as was suggested in the mid-19th Century. The existence of a functional secondary palate in the Plesiosauria is therefore strongly supported, and the anatomical, physiological, and evolutionary implications of such a structure are discussed.

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We here describe the rostrum of a pliosaur from the Kimmeridgian of northeastern Mexico. The specimen comes from the Upper Jurassic La Casita Formation (Kimmeridgian - Tithonian) and represents one of the few Plesiosauria in the area. The internal anatomy of the specimen is partly visible through cross-sections, which reveal a hitherto undescribed rostral prolongation of a paired bone of the interorbital area, probably the parietal or frontal beneath the premaxillae. The specimen also provides new information on the morphology and function of the choanae. In light of these morphological data, the new pliosaur shows similarities both with the European Late Jurassic genus Pliosaurus and the Australian Early Cretaceous Kronosaurus.

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[ES]Se describe una nueva especie del género Uromastyx sobre la base de dos especímenes procedentes del Adrar Sutuf (Sahara Occidental). Los individuos del nuevo taxón difieren fuertemente de Uromastyx acanthinura por el gran tamaño que llegan a alcanzar los adultos, su siempre mayor número de escamas, la disposición diferente de los tubérculos en los muslos, y por su diseño y coloración. Sus características generales se asemejan a las de Uromastyx aegyptia, un hecho que sugiere la posible existencia de lagartos del complejo U. aegyptia en poblaciones relícticas a lo largo del desierto del Sahara.

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[EN] Gallotia simonyi (Steindachner, 1889) is a member of an endemic Canary Island genus and is among the largest of the approximately 250 recent species of lacertid lizards. Although Steindachner gave the locality of the types as the Roques de Salmor, off El Hierro island, previous workers (Urusaustegui, 1983; Manrique & Saavedra, 1873; Viera & Clavijo, 1983) and subsequent ones (Machado, 1985) regard the more western of the two rocks in the group, the Roque Chico de Salmor, as the actual source of material. The Roque Chico is 37 m high with a surface area of less than 10,000 m2 and lies 830 m from the northern coast of El Hierro (Machado, 1985).

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报道了锦蛇属团花锦蛇( E. davidi) 、绿锦蛇( E. prasina) 和三索锦蛇( E. radiata) 3 个种的核型和Ag - NORs ,团花锦蛇的核型2 n = 36 (8V + 6sV + 2I + 20M) ;绿锦蛇的核型2 n = 36 (7V + 7sV + 2I + 20m) ,三索锦蛇的 核型2 n = 40 (6V + 3sV + 2sI + 5I + 24m) ; ①团花锦蛇和绿锦蛇的染色体数目和结构与此属大多数种的相似, ; ② 此属种类的性染色体为ZW型,绿锦蛇的性染色体为第4 对大染色体,三索锦蛇的为第5 对大染色体,团花锦蛇 由于为雄性,未见染色体异型. ③Ag - NORs 在数目及在染色体上的位置均不相同,团花锦蛇的NORs 在第9 对 染色体上,数目为2 个;绿锦蛇的NORs 在第5 对染色体上,数目为4 个;三索锦蛇的NORs 在第4 对大染色体上, 数目为4 个; ④我们发现三索锦蛇较为特殊,其染色体数目、形态、性染色体的位置和形态及Ag - NORs 均与其 它种类不同. 可能的原因是此物种在核型演化过程中发生过染色体断裂和重排事件,提示三索锦蛇可能是一个 特化的类群. ⑤锦蛇属的种类可分为包括三索锦蛇为特殊的一组的4 个组. 图版1 表2 参18

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The general distribution of monogenean parasites of aquatic vertebrates inhabiting Chinese inland waters is summarised. Five hundred and seventy-two out of a total of 581 species of monogeneans were discovered on fish, while only nine species were found on Amphibia and Reptilia. Most dactylogyrids and diplozoids parasitise cyprinids, while ancyrocephalids occur on silurids and cyprinids, and gyrodactylids are found mainly on cyprinids and cobitids. Analyses of host-specificity and host-diversity suggests that the family Ancyrocephalidae should be divided into several families parallel with the Dactylogyridae. Of 12 subfamilies of the Cyprinidae, only the Gobiobotinae was found to be free of infection with monogeneans, and the genus Dactylogyrus has more species than any other monogenean genus associated with every cyprinid subfamily.

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沙蜥属Phrynocephalus Kaup,1825隶属于爬行纲(Reptilia)有鳞目(Squamata)蜥蜴亚目(Lacertilia)鬣蜥科(Agamidae),是欧亚大陆荒漠和稀疏草原常见蜥蜴。沙蜥属的分类及系统演化关系、地理分布格局与新生代第三纪以来古地中海的变迁、青藏高原的抬升及亚洲内陆干旱荒漠化的过程有密切的关系,长期以来有关沙蜥属的研究一直受到中外学者们的关注。由于沙蜥属地理分布广、形态变异大、体色和斑纹变化复杂,虽然前人使用过许多形态性状来描述和分类沙蜥属物种,但是仍然存在许多问题。性状的分类学意义不明确是造成这些问题的主要原因之一,因此本研究针对沙蜥属常用的鉴别性状进行分类意义的分析,希望能对沙蜥属物种鉴定及分类学其它研究有所裨益。 中国沙蜥属物种主要分布于西北的干旱荒漠区域及青藏高原的大部分地区,大约为18种。 本文研究了中国境内12种沙蜥:青海沙蜥(Phrynocephalus vlangalii)、西藏沙蜥(P. theobaldi)、南疆沙蜥(P. forsythii)、变色沙蜥(P. versicolor)、旱地沙蜥(P. helioscopus)、荒漠沙蜥(P. przewalskii)、乌拉尔沙蜥(P. guttatus)、草原沙蜥(P. frontalis)、叶城沙蜥(P. axillaris)、白稍沙蜥(P. koslowi)、无斑沙蜥(P. immaculatus)和白条沙蜥(P. albolineatus),对它们的65项外部形态性状进行了观察和测量,其中数量性状29项、质量性状36项。评价了这些性状的序级性、间断性和代表性,结论如下: 1. 对于数量性状,得出了适合各级分类的数值区间; 2. 给出了在不同序级上适合分类的质量性状。 并利用各性状评价的结果,给出12种沙蜥的检索表,以及对中国沙蜥物种某些尚存在争议的问题进行了探讨。 详细记录了青海沙蜥红原亚种的骨骼系统,首次发现并命名了肘骨(elbow bone)和垫骨(stepping bone),为沙蜥属系统学研究补充了骨骼方面的证据;解剖了乌拉尔沙蜥、旱地沙蜥、荒漠沙蜥的雌体和雄体的骨骼系统,并在14项骨骼形态性状上对这3种沙蜥进行了比较。 Phrynocephalus (Squamata,Agamidae) is a familiar genus of lizards inhabited desert and sparse steppes in Eurasia. The taxonomics, phylogenetics and distribution pattern of Phrynocephalus are relative intensely to these events: the vicissitudes of the archaic Mediterranean sea since the Cainozoic, the uplift of Qingzang Plateau and the expending arid areas in the inland of Asia. Owing to the wide distribution, the large variability of the morphology and the different colors in Phrynocephalus, it is difficult to identify them. Tough many morphological characters are used to describe and discriminate them,a lot of questions still exist. One of the most important reasons is the confusion in the morphological characters. In this study, we demonstrate the validity and the invalidity of the familiar characters. There are about 18 species of the genus Phrynocephalus in China, which exist in arid desert in Northwest China and Qingzang Plateau. Twelve Chinese species was analyzed in this paper. They are P. vlangalii,P. theobaldi,P. forsythia,P. versicolor,P. helioscopus,P. przewalskii,P. guttatus,P. frontalis,P. axillaris,P. koslowi,P. immaculatus,P. albolineatus. We measure 29 quantitative characters and observe 36 qualitative characters in each individual. Through analyzing these characters, we made some conclusions as follows: 1. to every quantitative character, we get a clear numeric area to discriminate the different operational taxonomic units. 2. we chose the valid qualitative characters in these operational taxonomic units. This paper is the first to describe the “elbow bone”, which is a bone in pectoral appendage equivalent to patella,and “stepping bone”, which is a bone under carpal. A detailed description of the skeletal system of female Phrynocephalus vlangalii hongyuanensis was conducted. We also anatomise the skeletal systems of three species: P. guttatus,P. przewalskii,P. helioscopus, and compare or contrast 14 skeletal characters in them. What’s more,this paper offers some suggestions to the questions of Chinese Phrynocephalus species and keys to 12 species of Phrynocephalus basing on our conclusions on the evaluation of the morphological characters.

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The common lizard (Zootoca vivipara) is Ireland’s only native reptile, forming a key part of the island’s biodiversity. However, there is a general paucity of distributional and abundance data for the species. In this study, we collated incidental records for common lizard sightings to define the distribution of the species in Northern Ireland. Maximum entropy modelling was employed to describe species-habitat associations. The resulting predicted landscape favourability was used to evaluate the current status of the species based on the distribution of its maximum potential range in relation to the degree of fragmentation of remaining suitable habitat. In common with previous studies in the Republic of Ireland, sightings were highly clustered indicating under-recording, observer bias, and fragmentation of suitable habitat. A total of 98 records were collated from 1905 to 2009. The species was recorded in 63 (ca. 34%) of 186 × 10 km Northern Irish grid squares. Lizard occurrence was strongly and positively associated with landscapes dominated by heathland, bog and coastal habitats. The single best approximating model correctly classified the presence of lizards in 84.2% of cases. Upland heath, lowland raised bog and sand dune systems are all subject to Habitat Action Plans in Northern Ireland and are threatened by conversion to agriculture, afforestation, invasive species encroachment and infrastructural development. Consequently, remaining common lizard populations are likely to be small, isolated and highly fragmented. Establishment of an ecological network to preserve connectivity of remaining heath and bog will not only benefit remaining common lizard populations but biodiversity in general.

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Phylogenetic relationships and divergence times for 10 populations of the three recognized ""species"" of Brazilian lizards of genus Eurolophosaurus were estimated from 1229 bp of cyt b, COI, 12S, and 16S rRNA mitochondrial gene segments. Eurolophosaurus is monophyletic and the basal split within the genus separates E divaricatus from a clade comprising E amathites and E nanuzae. Three populations of E divaricatus, which occurs along the western bank of Rio S (a) over tildeo Francisco, were consistently grouped together. Oil the east bank of the river, E amathites and E nanuzae from state of Bahia were recovered as the sister group of E nanuzae populations from state of Minas Gerais. The paraphyly of E nanuzae and the high divergence levels among populations of E divaricatus strongly suggest that species limits in Eurolophosaurus should be revised. Even considering an extreme evolutionary rate of 2.8% sequence divergence per million years for the four gene segments analyzed together, E. divaricatus would have separated from the two other species by at least 5.5 my ago, and E. amathites from E nanuzae populations from Bahia and Minas Gerais, respectively, by 1.5 and 3.5 my. The paleolacustrine hypothesis and changes in the course of the river potentially explain faunal divergence in the area, but divergences are much older than previously admitted. (C) 2007 Elsevier Inc. All rights reserved.