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The article discusses that how the term "snake" was still associated with long queuing for bananas or other rarities for everyday life. It mentions about the narrow travel corridor that only crossed south-east Europe to Ahtopol on the Black Sea. It discusses that breeding behavior of the Scheltopusik Pseudopus.

In this article, author talks about his visit to the Serra da Sao Mamede National Park in Portugal having species-rich herpetofauna including species of snakes. It mentions about the finding the horseshoe snake Hemorrhois hippocrepis and the western hooded snake Macroprotodon brevis ibericus. It discusses about the structures such as water points and stone walls in the park.

The emerging picture of non‐monophyly of scolecophidian snakes is increasingly indicative that fossorial lifestyle, myrmecophagous diet, and miniaturisation are powerful drivers of morphological evolution in squamate skulls. We provide a detailed description of the skull of Xenotyphlops grandidieri, with reference to the skulls of other scolecophidian snakes. The skull, which shows dramatic ventral inflection of the snout complex, is remarkably bizarre, and the mouth opening is more ventrally oriented than in other typhlopoids. The eyes are strongly reduced, and the enlarged and rather flat anterior head shield is covered in numerous sensillae. We put forward several potential explanations for the evolution of these unusual modifications. On the other hand, Xenotyphlops shares numerous synapomorphies with other typhlopoid snakes, including the highly specialized jaw mechanism. We argue that the key differences between the jaw mechanisms of Leptotyphlopidae, Anomalepididae, and Typhlopoidea provide compelling evidence for a strong role of convergence in the evolution of the scolecophidian bauplan, and these clades therefore cannot be interpreted as representative of ancestral anatomy or ecology among snakes. [ABSTRACT FROM AUTHOR]

The current proposal about the variation of standard metabolic rates (SMR) in snakes predicts that SMR is influenced by the feeding frequency (frequent or infrequent feeders). However, feeding frequency in snakes is poorly studied and hard to quantify under natural conditions. Alternatively, foraging strategy was studied for a large number of species and is usually related to the feeding frequency. In this work, we performed a meta-analysis on the SMR of compiled data from 74 species of snakes obtained from the literature and five more different species of lanceheads (genus Bothrops), after categorization according to the foraging mode (ambush or active foraging) and regarding their phylogenetic history. We tested the hypothesis that foraging mode (FM) is a determinant factor on the interspecific variation of SMR despite the phylogenetic relationship among species. We demonstrated that FM predicted SMR, but there is also a partial phylogenetic structuration of SMR in snakes. We also detected that evolution rates of SMR in active foragers seem to be higher than ambush-hunting snakes. We suggested that foraging mode has a major effect over the evolution of SMR in snakes, which could represent an ecophysiological co-adaptation, since ambush hunters (with low feeding rates) present a lower maintenance energetic cost (SMR) when compared to active foragers. The higher SMR evolution rates for active foraging snakes could be related to a higher heterogeny in the degree of activity during hunting by active foragers when compared to ambush-hunting snakes. [ABSTRACT FROM AUTHOR]

Secondarily marine tetrapods have evolved adaptations to maintain their osmotic balance in a hyperosmotic environment. During the transition to a marine habitat, the evolution of a euryhaline physiology likely encompassed successive changes in behavior and physiology that released organisms from regular access to fresh water. Deciphering these key steps is a complicated task. In this study, we investigated a species of freshwater natricine snake in which some populations are known to use marine environments. We experimentally subjected 30 adult Dice snakes ( Natrix tessellata ) from a population inhabiting the Black Sea coast to three salinities corresponding to freshwater (~ 0.1‰), brackish water (~ 15.0‰), and full-strength seawater (~ 34.0‰) in order to investigate their physiological (variation of body mass, osmolality) and behavioral (activity, drinking behavior) responses to salinity. Our results show that coastal Dice snakes from the study population are relatively tolerant to salinity close to that recorded in the Black Sea, but that prolonged exposure to full-strength seawater increases osmolality, stimulates thirst, decreases the activity of snakes and may ultimately jeopardize survival. Collectively with previously published data, our results strongly suggest specific physiological adaptations to withstand hyperosmolality rather than to reduce intake of salt, in coastal populations or species of semi-aquatic snakes. Future comparative investigations of Dice snakes from populations restricted to freshwater environment might reveal the functional traits and the behavioral and physiological responses of coastal N . tessellata to life in water with elevated salinity. [ABSTRACT FROM AUTHOR]

Animals typically respond to environmental variation by adjusting their physiology, behavior, or both. Ectothermic animals are particularly sensitive to microclimatic conditions and behaviorally thermoregulate to optimize physiological performance. Yet, thermoregulation can be costly and may obligate a physiological tradeoff with water loss. Presumably, this tradeoff intensifies when animals undergo necessary life-history events (e.g., pregnancy or digestion) that impose significant behavioral and physiological changes, including shifts in behavioral thermoregulation and increased metabolic rate. Thus, behavioral responses, such as modified microclimatic preferences, may help mitigate the physiological tradeoff between thermoregulation and water loss. Herein, we examined the influence of major physiological states (specifically, pregnancy, ecdysis, and digestion) on evaporative water loss and on behavioral adjustments in a viviparous snake, Vipera aspis . First, we used open-flow respirometry to measure the effects of physiological states and microclimatic conditions (temperature and humidity) on the rate of total evaporative water loss (TEWL) and metabolic rate (rate of O 2 consumption, V ˙ O 2 ). Then, we experimentally tested the influence of physiological state on microclimate selection. We found that energy-demanding physiological states were associated with i) an increased rate of TEWL and V ˙ O 2 compared to control states and ii) a slight preference (statistically marginal) for both warm and humid conditions compared to controls, suggesting a state-specificity in behavioral response. Overall our results underline the impact of physiological state on water loss and demonstrate the potential for behavior to mitigate the physiological tradeoff between thermoregulation and water balance. [ABSTRACT FROM AUTHOR]

Traversing gaps with different orientations within arboreal environments has ecological relevance and mechanical consequences for animals. For example, the orientation of the animal while crossing gaps determines whether the torques acting on the body tend to cause it to pitch or roll from the supporting perch or fail as a result of localized bending. The elongate bodies of snakes seem well suited for crossing gaps, but a long unsupported portion of the body can create large torques that make gap bridging demanding. We tested whether the three-dimensional orientation of substrates across a gap affected the performance and behavior of an arboreal snake (Boiga irregularis). The snakes crossed gaps 65% larger for vertical than for horizontal trajectories and 13% greater for straight trajectories than for those with a 90deg turn within the horizontal plane. Our results suggest that failure due to the inability to keep the body rigid at the edge of the gap may be the primary constraint on performance for gaps with a large horizontal component. In addition, the decreased performance when the destination perch was oriented at an angle to the long axis of the initial perch was probably a result of the inability of snakes to maintain balance due to the large rolling torque. For some very large gaps the snakes enhanced their performance by using rapid lunges to cross otherwise impassable gaps. Perhaps such dynamic movements preceded the aerial behavior observed in other species of arboreal snakes. [ABSTRACT FROM AUTHOR]

Abstract: Physiological investigations of snakes have established the importance of heart position and pulmonary structure in contexts of gravity effects on blood circulation. Here we investigate morphological correlates of cardiopulmonary physiology in contexts related to ecology, behavior and evolution. We analyze data for heart position and length of vascular lung in 154 species of snakes that exhibit a broad range of characteristic behaviors and habitat associations. We construct a composite phylogeny for these species, and we codify gravitational stress according to species habitat and behavior. We use conventional regression and phylogenetically independent contrasts to evaluate whether trait diversity is correlated with gravitational habitat related to evolutionary transitions within the composite tree topology. We demonstrate that snake species living in arboreal habitats, or which express strongly climbing behaviors, possess relatively short blood columns between the heart and the head, as well as relatively short vascular lungs, compared to terrestrial species. Aquatic species, which experience little or no gravity stress in water, show the reverse — significantly longer heart–head distance and longer vascular lungs. These phylogenetic differences complement the results of physiological studies and are reflected in multiple habitat transitions during the evolutionary histories of these snake lineages, providing strong evidence that heart-to-head distance and length of vascular lung are co-adaptive cardiopulmonary features of snakes. [Copyright &y& Elsevier]

In Omar Torrijos National Park, Coclé Province, Panama, we visually located Cope's vine snakes Oxybelis brevirostris at night along trails and streams. Of 203 O. brevirostris located, we documented height of perch for 185 individuals during March 2005-March 2007. All sleeping snakes encountered were on vegetation rather than on the ground. There was no significant difference in height of perch between males (170.1 cm) and females (148.7 cm). There, however, was a significant positive relationship between snout-vent length and height of perch. Longer snakes perched on branches significantly more often than small snakes, which tended to perch on herbaceous leaves. [ABSTRACT FROM AUTHOR]

After introducing the distribution and biology of Natrix tessellata in Israel, on the southern edge of its range, we address its intraspecific variation from the literature and examination of 262 museum specimens. Head pholidosis showed no significant directional asymmetry, but asymmetry in infralabial plates was significantly correlated with frequency of injured tails. Variation in body size showed no clear seasonal growth, presumably due to climatic fluctuations. The variation in number of ventrals (in males, 159-173, mode 165) was not geographical. Females attained 750-800 mm (head and body; mode 600-650) and males 700-750 (mode 500-600) mm. Females had significantly greater relative head length, and males significantly greater eye size relative to head length, counts of ventrals and of subcaudals, and relative tail length. The sexual dimorphism in relative tail length was evident also in juveniles. The sexual dimorphism varied geographically within Israel: that of head size was stronger in the south, that of relative tail length and number of subcaudals stronger in the north. Trunk coloration commonly comprised 6 rows of blackish spots of equal or different size. Head coloration in some individuals extraordinarily resembled that of Natrix natrix. We discuss some methodological problems and compare variation within Israel and with Anatolia. [ABSTRACT FROM AUTHOR]

Abstract: The utilization of venom in predatory and defensive contexts is associated with benefits regarding minimization of energetic expenditure on hunting, maximization of success in prey acquisition and avoidance of injury from dangerous prey and aggressors. Multiple characteristics suggest that venom is quite expensive to produce, thereby creating a tradeoff between advantages and disadvantages associated with its possession. The metabolic costs of venom production have rarely been studied and no information on the detailed metabolic processes during venom replenishment exists. Where costs of venom production have been studied they are often not in context with other components of the energy budget of the study organism. Using flow-through respirometry, we examined changes in metabolic rate in the Australian elapid Acanthophis antarcticus after venom expenditure and feeding as well as during preparation for shedding to establish a comparison of the magnitude of energetic expenditure during venom replenishment and other common physiological processes. We also defined the temporal pattern of metabolic processes during venom replenishment at a higher resolution than has previously been attempted in snakes. Our results suggest that total costs of venom replenishment are relatively small when compared to costs of digestion and shedding. We conclude that, in spite of the manifold factors suggesting a high cost of venom in snakes, its production is less energetically costly than often assumed. Until further research can clarify the reasons for this more caution should therefore be applied when assuming that costs of venom production exert strong selection pressures on the ecology, behavior and evolution of venomous taxa. [ABSTRACT FROM AUTHOR]

Among snakes, the magnitude to which intestinal performance is regulated with feeding and fasting is adaptively linked to their natural feeding frequency. For infrequently feeding boas and pythons, gastrointestinal form and function are widely regulated with each feeding bout. In contrast, snakes that naturally feed more frequently modestly regulate intestinal function with each meal. To further explore the postprandial responses of a frequently feeding snake and assess whether such responses are matched in magnitude, we examined the postprandial metabolic, morphologic, and functional responses of the diamondback water snake (Nerodia rhombifer) following the consumption of catfish meals equaling 25% of their body mass. After feeding, N. rhombifer experienced 5.4-fold increases in metabolic rate and a specific dynamic action of 101 kJ that equaled 25.3% of the ingested energy. Nerodia rhombifer that were fed did not undergo any change in stomach tissue mass but did experience a rapid drop in gastric pH and a decline in tissue stores of pepsinogen. Feeding triggered an increase in pancreatic mass and a temporary loss of trypsin activity. The small intestine of N. rhombifer responded to feeding with a 70% increase in mass and a 27% increase in enterocyte length but no change in microvillus length. Intestinal nutrient uptake rates did not increase with feeding, whereas intestinal aminopeptidase-N activity increased by fivefold. The postprandial increases in metabolism and gastrointestinal morphology and function of N. rhombifer are of a lower magnitude than is characteristic of infrequently feeding snakes and are more similar to the responses observed for other frequently feeding species. In support of an adaptive interplay between feeding habits and digestive physiology, this study demonstrates that the regulation of gastrointestinal structure and function for the frequently feeding N. rhombifer is generally modest and matched in magnitude. [ABSTRACT FROM AUTHOR]

The article discusses the rediscovery of Taeniophallus poecilopogon in Argentina, which is a snake that belongs to colubrid snake genus, Taeniophallus. It mentions that only two species of the genus are said to occur in Argentina, the Taeniophallus poecilopogon and Taeniophallus occipitalis. It says that Taeniophallus poecilopogon's second specimen was found in Buenos Aires in Argentina on August 28, 2008. It describes the physical characteristics of the specimen which has 17 smooth dorsal scales without apical pits and reduction, the cloacal plate is divided, and the color pattern is longitudinally stripe. It adds that the place where the second specimen was discovered is part of the Talares district, Celtis tala, in the Espinal phytogeographic province.

In many animal species, mothers that produce stillborn offspring or undeveloped ova immediately ingest them. This cannibalism has been interpreted in two ways: (1) as a form of parental care (to prevent disease spreading to healthy littermates, and eliminate predator-attracting scent cues); or (2) to recycle otherwise wasted energy, thus facilitating maternal recovery. Our experimental study on captive Colombian rainbow boas (Epicrates cenchria maurus) provides the first quantitative support for this latter hypothesis. We show that by eating their non-viable offspring and undeveloped eggs, female boas can rapidly recycle a significant component of their otherwise wasted reproductive investment. Female boas that ingested non-viable progeny equivalent to half their litter mass exhibited rapid recovery of dorsal musculature and hence were able to constrict prey items more forcefully than were unfed females when tested 2 weeks after parturition. The consequent enhancement of constricting ability may influence maternal survival and foraging success. Thus, maternal cannibalism may be an effective tactic to avoid wasting reproductive resources, and to shorten the period required for recovery from pregnancy. © 2005 The Linnean Society of London,Biological Journal of the Linnean Society, 2005,84, 767–774. [ABSTRACT FROM AUTHOR]

The article focuses on the rediscovery, geographic distribution, and record of Taeniophallus poecilopogon in Corrientes, Argentina. It notes that this snake species is represented by two specimens. One of these specimens is located in Museuo Argentino de Ciencias Naturales Bernardino Rivadavia (MACN) in Buenos Aires. The other specimen is housed in the Museum of Zoology at the University of Torino. It also records the species from the province with voucher specimen and presents information on its parasitism, diet, and habitat.

The article focuses on the geographic distribution and record of reptilia Sibynomorphus lavillai in the state of Mato Grosso do Sul in Brazil. It notes that there are four species of genus Sibynomorphus formally reported in the country namely S. neuwiedi, S. ventrimaculatus, S. mikanii, and turgidus. It points out that there were 11 specimens caught in pitfall traps with drift fences. The survey shows that the specimens matched with the discriptions of the species provided in 1993 including the immaculate ventral pattern, the presence of blotches, and the moderately enlarged vertebral scale row.