Eighteen microsatellite loci developed for a range of snake species (New World natricines, elapids, crotalids) were tested against European natricines (Natrix natrix, N. maura, and N. tessellata) in cross-species amplification experiments. Five loci were polymorphic (average expected heterozygosity 0.749 for a population of N. natrix in Amsterdam, mean sample size 47.8) and three loci were mono...

a water snake (natrix natrix) was referred to the small animal teaching hospital, faculty of veterinary medicine, university of tehran. it had two subcutaneous masses. radiographic and ultrasonographic images revealed the presence of two subcutaneous abscesses. the abscesses were removed surgically and specimens were examined by conventional microbial culture and multiplex pcr. inv-a universal ...

Natrix chromatography membranes combine all the advantages of chromatographic resins (specificity, selectivity, high binding capacities) and conventional membranes (high throughput, ease of operation, scalability) in a single use format. Since Natrix membranes are inherently hydrophilic they are naturally resistant to fouling, and the Crossflow device formats permit simultaneous Clarification a...

Antipredatory defenses are maintained when benefit exceeds cost. A weak predation pressure may lead insular lizards to tameness. Podarcis lilfordi exhibits a high degree of insular tameness, which may explain its extinction from the main island of Menorca when humans introduced predators. There are three species of lizards in Menorca: the native P. lilfordi, only on the surrounding islets, and ...

Egg-clustering and communal nesting behaviours provide advantages to offspring. Advantages range from anti-predatory benefits, maintenance of moisture and temperature levels within the nest, preventing the eggs from rolling, to enabling hatching synchrony through embryo communication. It was recently suggested that embryo communication may extend beyond development fine-tuning, and potentially ...

Bohr (1904) reported CO2 production of an embryo of Natrix natrix, weighing 0-46 g., to be 120 mm./g./hr. at 14-2° C ; the CO2 produced at 28 0 C. was 3 times that at 15 C , and production by a newly hatched snake at 15° C. was approximately 90 mm./g./hr. Other data are given, but they are not related to stage of development, and oxygen utilization was not measured. Zarrow & Pomerat (1937) made...

In cases of introductions where the exogenous species is morphologically and ecologically very convergent with one, or more, of the native species, the potential for resource (trophic, territory, sun, shelter, etc.) competition is high. In this regard we investigated in 2007 and 2008 the potential role of trophic resource competition in the invasive-native species system Natrix maura-N. tessell...

It is a common belief that reptile eggs should not be turned after oviposition once the embryo has attached itself to the inner membrane of the shell as it might kill developing embryos. Here, we used 338 eggs from 32 clutches of the water snake Natrix maura to (1) thoroughly describe natural clutch arrangement, (2) experimentally assess the effects of natural embryo positioning and (3) egg tur...