Water Snake Research Articles

Evaluation of Nuvan Toxicity Stress on Blood Lipoprotein of Fresh Water Fish Channa punctatus

Organophosphate insecticide Nuvan (DDVP) has selected for the present study, Lethal concentrations were calculated for the fresh water snake headed fish Channa punctatus i.e 0.27ml/L after 24, 48, 72 and 96 hours. For the chronic study 1/10th of the Nuvan concentration (0.027ml/L) was provided to the observed fishes. Blood serum lipoprotein HDL, VLDL and LDL High Density lipoprotein, Very low Density lipoprotein and low density lipoprotein respectively were estimated after chronic toxic stress of Nuvan to fish Channa punctatus. Fish serum lipoprotein and HDL revealed significant decrease level while LDL and VLDL showed significant elevated level after 7, 14, 21, and 28 days at different level p <0.01 and p <0.001.All values are mentioned in graphs respectively.

Helminths of Liophis miliaris (Squamata, Dipsadidae): a list of species and new records

Summary In order to have better knowledge of the parasites of the common water snake Liophis miliaris (Linnaeus, 1758), a checklist of its helminths was produced based on a review of the literature and new records of worms identified during the course of a parasitological survey combining data from stool analysis (n = 22) and necropsies (n = 8) of specimens of this snake from Muriaé, state of Minas Gerais, Brazil. Thirty-one helminth species (two acanthocephalans, one cestode, 11 nematodes and 17 trematodes) were so far reported in L. miliaris in the Neotropical region, already including the records in the present study of Acanthorhabdias acanthorhabdias Pereira, 1927, Paracapillaria (Ophidiocapillaria) cesarpintoi (Freitas &amp; Lent, 1934) and Strongyloides ophidiae Pereira, 1929. Taxonomic comments on these nematode species are given, and areas of occurrence of A. acanthorhabdias and P. cesarpintoi are expanded in southeastern Brazil. In addition, factors related to parasite richness of L. miliaris, which is likely related to its aquatic habits, are discussed.

Daily and seasonal rhythms in immune responses of splenocytes in the freshwater snake, Natrix piscator.

Present study was designed to examine daily and seasonal variability in the innate immune responses of splenocytes in the fresh water snake, Natrix piscator. Animals were mildly anesthetized and spleen was aseptically isolated and processed for macrophage phagocytosis, NBT reduction, nitrite production, splenocyte proliferation and serum lysozyme activity. Samples were collected at seven time points, viz., 0000, 0400, 0800, 1200, 1600, 2000 and 0000 h during three different seasons, namely summer, winter and spring. Cosinor analysis revealed that percent phagocytosis had a significant 24-h rhythm during summer and spring seasons. The peaks of rhythms in NBT reduction and nitrite release occurred in the morning hours at 10.88 h and 8.31 h, respectively, in winter. A significant 24-h rhythm was also observed in lysozyme concentration and splenocyte proliferation (both Basal and Concanavalin A stimulated) in all three seasons. A significant phase shift in splenocyte proliferation was obtained with a trend of delayed phase shift from winter to spring and from spring to summer. Of the nine variables, significant annual (seasonal) rhythms were detected in almost all variables, excluding phagocytic and splenosomatic indices. All rhythmic variables, except spleen cellularity, exhibited tightly synchronized peaks coinciding with the progressive and recrudescence phases of annual reproductive cycle. It is concluded that the snake synchronizes its daily and seasonal immune activity with the corresponding external time cues. The enhancement of immune function coinciding with one of its crucial reproductive phases might be helping it to cope with the seasonal stressors, including abundance of pathogens, which would otherwise jeopardize the successful reproduction and eventual survival of the species.

Hepatozoon and Theileria species detected in ticks collected from mammals and snakes in Thailand

We report the detection of Hepatozoon and Theileria in 103 ticks from mammals and snakes in Thailand. By using a genus-specific 18S rRNA PCR, Hepatozoon and Theileria spp. were detected in 8% and 18%, respectively, of ticks (n=79) removed from mammals. Of the ticks removed from snakes (n=24), 96% were infected with Hepatozoon spp., but none were infected with Theileria. Phylogenetic analysis revealed that Hepatozoon spp. detected from Dermacentor astrosignatus and Dermacentor auratus ticks from Wild boar (Sus scrofa) formed a phylogenetic group with many isolates of Hepatozoon felis that were distantly related to a species group containing Hepatozoon canis and Hepatozoon americanum. In contrast, a phylogenetic analysis of the Hepatozoon sequences of snake ticks revealed that Hepatozoon spp. from Amblyomma varanense from King cobra (Ophiophagus hannah) and Amblyomma helvolum ticks from Indochinese rat snake (Ptyas korros), and Asiatic water snake (Xenochrophis piscator) are grouped with Hepatozoon spp. recently isolated from Monocellate cobras, Reticulated pythons and Burmese pythons, all of Thai origin, and with Hepatozoon sp. 774c that has been detected from a tick species obtained from Argus monitors in Australia. A phylogenetic analysis demonstrated that Theileria spp. from Rhipicephalus (Boophilus) microplus, Haemaphysalis obesa, and Haemaphysalis lagrangei ticks from Sambar deer (Cervus unicolor) cluster with the Theileria cervi isolates WU11 and 239, and Theileria sp. Iwate 141. We report for the first time a Hepatozoon species that shares genetic similarity with Hepatozoon felis found in Dermacentor astrosignatus and Dermacentor auratus ticks collected from Wild boars in Thailand. In addition, we found the presence of a Theileria cervi-like sp. which suggests the potential role of Haemaphysalis lagrangei as a Theileria vector in Thailand.

Snakes for lunch: bird predation on reptiles in a tropical floodplain

Based on collaboration between a wildlife photographer and a scientist, this paper provides novel information and images of predation by birds (Black-necked Storks, White-bellied Sea-Eagles, Whistling Kites) on reptiles (Macleay's Water Snakes, Keelback Snakes, Long-necked Turtles). The observations and photographs come from the wall of Fogg Dam, 60 km east of Darwin, the site of a long-term ecological research program on reptiles and amphibians. Professional ecologists rarely witness predation on their study animals, and this has been true at Fogg Dam despite ≯20 years' continuous research on reptiles at the site. The photographs provide the first specific records of predation upon reptiles by birds in this floodplain ecosystem.

Duvernoy's (Parotid) gland adenoma in Indian Water snake (Xenohrophispiscator)

Snake rescue team presented a Water snake (Xenohrophispiscator) with hemorrhagic swelling at the mouth part. It is incised which revealed multilobulated structure. Histopathologicalythere was tubuloacinar structures lined by single or multilayered epithelium;the tubular lumina were totally or partially filled with proliferating secretary epithelium and degraded material or necrotic cells. The tumor cells were cuboidal to polygonal and have an amphophilic or eosinophilic cytoplasm and large hyperchromatic nuclei. An interlobular stroma contained blood vessels with vacuolated endothelium and there were hemorrhages into surrounding area. Few mitotic figures were present. Intra luminal necrotic cells and an eosinophilic secretion were found in the center of tubular lumen.

ECOLOGY AND DIVERSITY OF WILDLIFE IN THE ECO-PARK OF THE JAMUNA BRIDGE AND ITS ADJACENT AREA, SIRAJGONJ, BANGLADESH

Animal diversity of an area is a good indicator for understanding a healthy habitat. We conducted a detail study on ecology and the wildlife diversity in the Eco-park of Jamuna bridge and its adjacent area of Sirajgonj district from April 2010 to March 2011. We employed transect line method and interviewed local people to reveal the status and distribution of wild animal and identify their microhabitats. A total of 89 species of wild animals was recorded, of which, 6 (6.74%) species were amphibians, 11 (12.36%) reptiles, 56 (62.93%) birds and 16 (17.94%) mammals. Regarding relative abundance, 18 (20.22%) species of wildlife were very common, 35 (39.33%) common, 28 (31.46%) fairly common, 7 (7.87%) few and only one (1.12%) was occasionally found. In total 25 species of wildlife were identified as threatened category. In amphibians, 3 species were vulnerable nationally. In reptiles, 4 species were vulnerable and one endangered. In birds, 4 species were vulnerable, 6 endangered and one critically endangered (Gallicrex cinerea). In mammals, 3 vulnerable and 3 endangered nationally. Among the amphibians, skipper frog (Euplyctis cyanophlyctis) and toad (Bufo melanostictus) frequently occurred. Among the reptiles, common garden lizard (Calotis versicolor), common skink (Mabuya carinata) and cheekered keel back water snake (Xenochorphis piscator) were frequently occurred. Among the birds, common myna (Acrodotheres tristis), pied myna (A. fuscus), black drongo (Dicrurus macrocercus) and house crow (Corvus splendens) occurred frequently. Among the mammals, shrew (Suncus murinus), flying fox (Pteropus giganteus) and black rat (Rattus rattus) frequently occurred. Our study shows that illegal exploitation of trees, overgrazing of domestic animals, shooting and collection of young animals are the mentionable causes for declining wild animals. We suggest that awareness creation and preparation of proper management action plan in cooperation with related national and international organizations are necessary in order to protect the wildlife resources in the study area. DOI: http://dx.doi.org/10.3126/eco.v20i0.11327Ecoprint: An International Journal of EcologyVol. 20, 2013Page : 27-36

Isolation and characterization of microsatellite markers in the Asiatic water snake (Xenochrophis piscator)

The Asiatic water snake (Xenochrophis piscator) is a small-sized snake and can be found in or near freshwater lakes or rivers. This species is listed in Appendis III of the Convention on International Trade in Endangered Species of Wild Fauna and Flora. We isolated and characterizated 9 polymorphic microsatellite loci in this species to evaluate their population polymorphism using 176 individuals collected from Quanzhou in southern China. These markers revealed a high degree of genetic diversity (20–50 alleles per locus) and heterozygosity (H O ranged from 0.137 to 0.944 and H E ranged from 0.884 to 0.953). No locus exhibited significant deviations from Hardy–Weinberg equilibrium. There was no evidence of linkage disequilibrium among pairs of loci. These microsatellite markers will be useful for future study of gene flow, population structure, and evolutionary history of X. piscator.

Paleoclimatic and paleoenvironmental context of the Early Pleistocene hominins from Dmanisi (Georgia, Lesser Caucasus) inferred from the herpetofaunal assemblage

Dmanisi is currently the oldest Early Palaeolithic site discovered out of Africa. It has produced over 40 hominin remains, including a set of very informative skulls, in direct association with faunal remains and numerous lithic artifacts. Given the relevance of this locality, every effort is being made to reconstruct the landscapes where these hominins once lived. Amphibian and reptile remains from Dmanisi are here described for the first time and used as paleoclimatic and paleoenvironmental proxies. They comprise at least six taxa: a green toad (Bufo gr. Bufo viridis), the Greek tortoise (Testudo graeca), a green lizard (Lacerta gr. Lacerta viridis), a four-lined snake (Elaphe gr. Elaphe quatuorlineata), an indeterminate colubrid and a water snake (Natrix sp.). As these taxa are not extinct and their ecology can be directly studied, they can contribute to the reconstruction of the landscape and climate. The application of the Mutual Climatic Range method provides quantitative data indicating that during the hominin presence at Dmanisi climate was warm and dry, similar to the present-day Mediterranean climate. In comparison with today climate of Dmanisi, estimated mean annual temperature was 3.1 °C higher, with a greater increase of temperature in summer (+7.1 °C) than in winter (+4.7 °C). The mean annual precipitation was slightly lower (−65 mm) than the current level, with precipitation higher than current one during winter (+104 mm) but strongly lower during the other seasons, suggesting a stronger contrast in the rainfall regime during the year. From a paleoenvironmental point of view, fossil amphibians and reptiles all suggest the predominance of arid environments, from steppe or semi-desert to open Mediterranean forest, with stony or rocky substrate and bushy areas. The presence of permanent aquatic environments is also documented. These results mainly agree with those for large mammals, small mammals and the archaeobotanical analysis that indicate an important water stress suggesting a period of increased aridity contemporaneous with human occupations of the site.

Isolation and characterization of microsatellite loci in the dog-faced water snake Cerberus rynchops (Colubridae)

The dog-faced water snake (Cerberus rynchops) is a viviparous colubrid snake. This species occurs in coastal South Asia, peninsular India, Sri Lanka, Bangladesh, Myanmar, the Andaman Islands, eastward to the coastal areas of the Indochinese and Malaysian Peninsulas, southwards into Indonesia and eastwards to Palau and Micronesia. It has been listed on Appendix III of CITES. In India, this species is protected under the Indian Wildlife Act, due to its historic trade as skin. Accordingly, we aimed to characterize new microsatellite markers, which could be helpful for us to get a better understanding of population structure and evolutionary history of the snake. Here, eight polymorphic microsatellite loci were isolated from an enriched genomic library of C. rynchops. One hundred and fifteen individuals were collected from Singapore. These markers revealed a high degree of genetic diversity (5–14 alleles per locus) and heterozygosity (HO ranged from 0.565 to 0.965, and HE ranged from 0.701 to 0.882). No locus exhibited significant deviations from Hardy–Weinberg equilibrium. There was no evidence of linkage disequilibrium between any pair of loci. These loci are first identified for C. rynchops and will be useful for future study of population structure, genetic diversity and conservation strategy design of this species.

Differential suppressive effects of testosterone on immune function in fresh water snake, Natrix piscator: an in vitro study.

Reptiles represent the crucial phylogenetic group as they were the ancestors of both birds and mammals hence very important to study. The objectives of the present study were to investigate the potential roles of testosterone in the innate immune responses and splenic lymphocyte proliferation in fresh water snake, Natrix piscator. Animals were mildly anesthetized and spleens were taken out to study the splenic macrophage phagocytosis, super oxide production and nitrite release using in vitro testosterone. Splenic lymphocytes were isolated by density gradient centrifugation and were studied for mitogen induced proliferation in presence of in vitro testosterone. Testosterone suppressed the phagocytosis and nitrite release in a concentration dependent manner. Biphasic suppressive effect of testosterone was observed in superoxide production as judged by reduction of nitroblue tetrazolium salt where salt reduction was suppressed at lower and higher concentrations of testosterone. Mitogen induced splenic lymphocyte proliferation was also suppressed by testosterone. By suppressing immune responses, testosterone may, therefore, act as a physiological mechanism regulating the relative amount of energy invested into either reproductive effort or immunocompetence.

The behavioural response of adult Petromyzon marinus to damage-released alarm and predator cues.

Using semi-natural enclosures, this study investigated (1) whether adult sea lamprey Petromyzon marinus show avoidance of damage-released conspecific cues, damage-released heterospecific cues and predator cues and (2) whether this is a general response to injured heterospecific fishes or a specific response to injured P. marinus. Ten replicate groups of 10 adult P. marinus, separated by sex, were exposed to one of the following nine stimuli: deionized water (control), extracts prepared from adult P. marinus, decayed adult P. marinus (conspecific stimuli), sympatric white sucker Catostomus commersonii, Amazon sailfin catfish Pterygoplichthys pardalis (heterospecific stimuli), 2-phenylethylamine (PEA HCl) solution, northern water snake Nerodia sipedon washing, human saliva (predator cues) and an adult P. marinus extract and human saliva combination (a damage-released conspecific cue and a predator cue). Adult P. marinus showed a significant avoidance response to the adult P. marinus extract as well as to C. commersonii, human saliva, PEA and the adult P. marinus extract and human saliva combination. For mobile P. marinus, the N. sipedon washing induced behaviour consistent with predator inspection. Exposure to the P. pardalis extract did not induce a significant avoidance response during the stimulus release period. Mobile adult female P. marinus showed a stronger avoidance behaviour than mobile adult male P. marinus in response to the adult P. marinus extract and the adult P. marinus extract and human saliva combination. The findings support the continued investigation of natural damage-released alarm cue and predator-based repellents for the behavioural manipulation of P. marinus populations in the Laurentian Great Lakes.

Анализ изменчивости морфологических признаков водяного ужа (Natrix tessellata) Волгоградской области

Анализ изменчивости морфологических признаков водяного ужа (Natrix tessellata) Волгоградской области

Isolation and characterization of microsatellite loci in the Chinese water snake Enhydris chinensis (Colubridae)

The Chinese water snake Enhydris chinensis is an ovoviviparous colubrid snake distributed in China and Vietnam. It is commonly used in the production of Chinese snake oil, which is known for treating ailments such as fever, joint pain, and headache. It is listed as a vulnerable species according to the China red data book of endangered animals. Specific molecular markers such as mitochondrial DNA and microsatellite loci are helpful for us to get a better understanding of population structure and evolutionary history of the snake and take effective conservation action for this species. Here, we characterize eight polymorphic microsatellite loci isolated from E. chinensis genomic libraries. Forty-seven individuals were collected from Ji’an population in Jiangxi, China. These markers revealed a high degree of genetic diversity (3–10 alleles per locus) and heterozygosity (H O ranged from 0.532 to 0.957, and H E ranged from 0.565 to 0.806). No locus exhibited significant deviations from Hardy–Weinberg equilibrium. There was no evidence of linkage disequilibrium among pairs of loci. The results of this paper will be useful for future study of population structure and genetic diversity of E. chinensis.

REPORT OF KERALA MUD SNAKE DIEUROSTUS DUSSUMIERII FROM A BEACH IN KOCHI, KERALA

The Kerala mud snake Dieurostus dussumierii (Dumeril, Bibron & Dumeril, 1854) is a little-known Homalopsid water snake endemic to southwestern Indian coastal plains (Chandramouli et al., 2012; Kumar & Captain, 2011; Kumar et al ., 2012). Precise locality records are from Thrissur to Thiruvananthapuram. Based on a recent molecular study (Kumar et al ., 2012), its generic allocation was reassessed and was changed from Enhydris to Dieurostus . It is locally known as “kanda pampu” (paddy snake) in southern Kerala and “cheli kutta” (mud snake) in the north, suggesting its affinity towards inhabiting freshwater marshlands and water-logged paddy fields (Chandramouli et al., 2012; Kumar & Captain, 2011). In this note, I report my record of Kerala mud snake from a sandy beach stretch adjoining the seacoast in Kochi, Kerala.

De naguales y culebras. entidades sobrenaturales y “guardianes de los pueblos” en el sur de oaxaca

This article aims to analyze a series of stories about naguales of the zapotecs from the south of Oaxaca, the most of which refer the water snake as a supernatural protective entity of communities against attacks by naguales of other villages, especially the huave people from San Mateo del Mar, in the region of the Isthmus of Tehuantepec. These stories are integrated in a complex context of interethnic relations among peoples of various groups that have lived in the south fringe of state –among them zapotecs, chontals, mixes, zoques and huaves–, comprising the regions of the Southern Highlands, Coast and the Istmo of Tehuantepec. The analysis was done from two aspects: the character of the naguales as supernaturals entities that protect the villages, and the local stories and ethnic relations among zapotecs villages from south and huaves from San Mateo del Mar.

A Mark-Recapture Study Of A Dog-Faced Water Snake Cerberus Schneiderii (Colubridae: Homalopsidae) Population In Sungei Buloh Wetland Reserve, Singapore

Ecological traits of a relatively sheltered population of the dog-faced water snake, Cerberus schneiderii, were determined or estimated using mark-recapture data. Monthly surveys were conducted at the man-made brackish ponds at Sungei Buloh Wetland Reserve, Singapore throughout the year 2006. Estimates of population density (102 snakes ha -1 ), snake biomass (4.1 kg ha -1 ) and relative abundance (5.4 snakes man-hour -1 ) provided evidence of a large population. Sex ratio was almost 1:1. Snakes from a wide range (145-720 mm SVL) of body size were present. Even though neonates were rarely encountered, 88.7% of adult females have reached the size of sexual maturity (SVL = 336 mm SVL). There was no seasonal variation in the population's size structure, suggesting that recruitment occurred throughout the year. Most of the snakes were sedentary and more than 90% of them remained in the same pond that they were captured for the fi rst time. During low tides, snakes had a tendency of congregating at the relatively deep waters close to the sluice gates and in the network of tidal streams and pools in the man-made ponds. The population exhibited sexual dimorphism, in terms of males having relatively longer tails and females possessing relatively wider heads.

First Cytogenetic Study of Puff-Faced Water Snake, &lt;i&gt;Homalopsis buccata&lt;/i&gt; (Squamata, Colubridae) by Conventional Staining, Ag-NOR Banding and GTG-Banding Techniques

Summary The first cytogenetics of the puff-faced water snake (Homalopsis buccata) from Khon Kaen Province, Thailand was obtained from the present study. Mitotic chromosome was prepared directly from the spleens of specimens after in vivo colchicines treatment. The metaphase spreads were performed on microscopic slides and air-dried. Conventional staining, Ag-NOR banding, and GTG-banding techniques were applied to stain the chromosome with Giemsas solution. Results showed that the number of diploid chromosome was 2n=36, while the fundamental number (NF) was 52 in both males and females. The types of macrochromosome were four large metacentric, two medium metacentric, six small metacentric, and two small acrocentric chromosome, and 20 micro- chromosomes. It was found that nucleolar organizer regions (NORs, the representative of chromo- some marker) locate on the long arms near centromeres of a pair of microchromosomes, pair 15. The Z chromosome was a small metacentric chromosome, while the W chromosome was a small sub- metacentric chromosome. From the GTG-banding technique, it was found that each chromosome pairs could be clearly differentiated and the numbers of bands in the H. buccata was 109. The karyo- type formula is as follows: 2n (36)=L m 4 +M m 2 +S m 6 +S a +20 microchromosomes+sex chromosomes (ZW)

The dog-faced water snakes, a revision of the genus Cerberus Cuvier, (Squamata, Serpentes, Homalopsidae), with the description of a new species

The dog-faced water snakes, a revision of the genus Cerberus Cuvier, (Squamata, Serpentes, Homalopsidae), with the description of a new species

Assessement of nuvan toxicity to lipids in snake headed fresh water fish Channa punctatus

The healthy functioning of the biosphere in our planet, the life depends entirely on the water flow and steady state phenomenon. Lethal concentration of Nuvan calculated for the fresh water snake headed fish Channa punctatus 0.27ml/L after 24, 48, 72 and 96 hours. For the chronic study 1/10th Nuvan concentration (0.027ml/L) provided to observe fish. Blood serum cholesterol (Chol.) and triglycerides (TG) estimated after chronic toxic stress of Nuvan to fish Channa punctatus. Fish serum TG revealed significant decrease level while Cholesterol showed significant elevated level after 7, 14, 21, and 28days at different level p &gt; 0.05, p &lt;0.01 and p &lt;0.001 in fresh water fish Channa punctatus.