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Snakes-their classification and Distribution in India






Snakes-their classification and Distribution in India





E.Kunhikrishnan
Sr.Lecturer, Department of zoology
H.H.Maharaja University College
Thiruvananthapuram



INTRODUCTION
There are about 2920 species of snakes belonging to 445 genera in the world; under 18 families
About 200 species are found in India.The maximum diversity of snakes in India is in the Western Ghatsand in the  North east
The snakes are commonly divided in to two infraorders , Alethinophidia with  15 families and  Infraorder Scolecophidia with 3 families 
The pattern of scale arrangement and the configuration of scales provide the most useful basis for identification. The  first step in learning to use dichotomous keys for snake identification is to become acquainted with the typical "scalation".
The scales on a snake's body are either "smooth" or "keeled". A keeled scale has a ridge down the middle of the scale. A smooth scale has no ridge. 
The cloacal opening is covered with a scale, the anal, which may be single or divided into 2 parts. 
Anatomical features of the skull is important. The change in size and position of the quadrate, the vestiges of the pelvis, the structure and the position of fangs etc also differ from group to group. The arrangement of the scales on the head, viz.  nasal, internasal, prefrontal, frontal, supraoccular, parietal,rostrla, loreal, upperlabials, lowerlabials, post ocular and temporal help in distinguishing family, genera and species. The number of scales in the dorsal row is also taken in to consideration.

NONPOISONOUS SNAKES
Family  Typhlopidae. Scales uniform.  Typhlops consists of two Genera and 21 species (Indian sub-continent). They are tiny worm-like burrowing snakes which are non-poisonous. There are at least 14 species in India , five occurring in Kerala.
Family  Uropeltidae   consist of burrowing snakes seen only in  peninsular India and Sri Lanka. Total  47 species in the world  of which 33 endemic to the Peninsular India. A group of great interest. 
Family Boidae   Include the biggest snakes in the world-boas and pythons  
There are two species of pythons in IndiaPython molurus - Indian Rock python and P. reticulatus-Nicobar Islands 
Genus Eryx consists of three species in India E.conicus, E.johnii and E. whitekeri 
Family Dipsadidae  Contain  some common snakes Genus like Lycodon.( Wolf snakes ). Misidentification of these harmless snakes creates problems because of their superficial resemblance to the deadly Kraits.
Eight species in India. Three in south IndiaLycodon travancoricus (Travancore wolf snake), L. striatus  (barred wolf snake )and L. aulicus  (Common wolf snake )
Genus  Oligodon (Kukri Snakes) can be distinguished by peculiarand  prominat markings and pattern  on the head. 18 species in the Indian region; seven species present in south India, others in North east and in eastern Himalayas 
Genus  Amphiesma .Eight species. Three in Western ghats and south IndiaA. stolata (stripped keel back), A. beddome (Beddome's keelback) and A. monticola (green western keelback).

Genus Dendrelaphis -(Tree snakes) seven species in India. Five in south India, D. pictus (painted bronze back tree snake) D. grandoculis (large eyed brown tree snake)  D. bifrenalis( Boulenger's bronzeback treesnake ) D caudolineata (Stripetailed bronzeback tree snake )and  D. tristis (common bronzeback treesnake )

Family Colubridae includes well over half of all snake species on earth. Colubrid species are found on every continent, except Antarctica. There are 1938 species under 304 genera the world over. (All other snake species put together is about 980). While most colubrids are non-venomous (or have venom that isn't known to be harmful to humans) and are normally harmless, a few groups, such as genus Boiga, can produce medically significant bites, while the boomslang and the twig snakes have caused human fatalities. The venom is a modified form of saliva, secreted by glands in the upper jaw. The venom-injecting fangs of colubrids are termed opisthoglyphous, meaning that the small, grooved fangs are located in the back of the upper jaw, unlike those of vipers and elapids, which are located in the front. Even non-venomous colubrids often have fangs in this position, and use them to puncture egg-shells or similar food. Classification of Colubridae based mainly on dentition and other features. There are 3 sections. They are 1 Aglypha with solid ungrooved teeth, 2 Opisthoglypha with teeth are grooved and connected to poison-glands, 3 Proteroglypha with canaliculated anterior maxillary teeth (front-teethed) they are very poisonous. 
Aglyphous ("lacking grooves") snakes have no specialized teeth - each tooth is more or less the same in shape and often in size. When some teeth are larger than others, as is sometimes the case in bird eaters such as Corralus, the enlarged teeth are merely "scaled up", and are otherwise identical. Aglyphous snakes are non-venomous, and can be found in numerous families. Opisthoglyphous ("rearward grooves") snakes are similar to aglyphous snakes, but possess weak venom, which is injected by means of a pair of enlarged teeth at the back of the maxillae. These "fangs" typically point backwards rather than straight down, possess a groove which channels venom into the prey, and are located roughly halfway back in the mouth, which has led to the vernacular name of "rear-fanged snakes". This combination of features means that, in order to envenomate prey, the snake must bite it, move the prey into the back of the mouth, then penetrate it with the grooved fangs, which allow venom secreted into the mouth to seep into the prey. This presents difficulties with large prey items, though they can quickly move smaller prey (or a human handler's finger) into position. While the venom of most opisthoglyphous snakes is so weak that it does not affect humans, a few are capable of delivering harmful or even fatal bites. Notably, herpetologists Karl Schmidtt and Mertens were killed by aboomslang and theletornis, respectively, after each underestimated the effects of the bite and failed to seek medical help 
Proteroglyphous ("forward grooved") snakes have a much more sophisticated venom delivery method. These snakes have shortened their maxillae, which bears few teeth except for a substantially enlarged "fang" located at the front of the mouth. Unlike the opisthoglyphous snakes, the fangs of proteroglyphs point downwards and completely fold around the venom channel, forming a hollow needle with which to inject their venom more effectively. However, because the fangs are only a fraction of an inch long in even the largest species (and often much shorter) these snakes must still hang on, at least momentarily, as they inject the venom. The venom of proteroglyphs is the most toxic of all snakes, and among the most toxic natural substances in the world. This form of dentition is unique to elapids.
A few species of spitting cobras have modified opening at the tip of the fang which allows them to spray venom at an attacker's eyes. 
Subfamily  Colubrinae, is with over 100 genera and roughly 650 species in the world 
Genus  Elaphe -Nine species in Indian region but only one(Elaphe helena)--trinket snake) present in south India others are  in north east. 
Genus Chrysopelea -flying snakes- only two species, Chrysopelea ornata in the Western Ghats , Orissa, Bengal and the other species in Narcondam, Andaman islands. 
Genus Ahaetulla -vine snakes-6 species 4present in south India . A. nasutus is the  common vine snake. 
Family Homalapsidae 
Subfamily Boiginae –
Genus Boiga- Cat snakes ; 11 species  4 in south India; others in Assam and in northeast 
Genus Enhydris    include the Water snakes Three species, only two in south india.

POISONOUS SNAKES
Family Elaphidae: cobras; kraits; mambas; coral snakes; Australian taipan and tiger snakes 
Genus Bungarus (Kraits ) Sevenspecies  in Indian subcontinent. Only one in south India -B. caeruleus(Common krait). One of the most deadliest snake and is one of the "big four" snakes in India. Neurotoxicand quickly induces muscle paralysis. Clinically, their venom contains pre-synaptic neurotoxins. 
Genus Callophis (Coral snakes ) As the name indicates, beautifully coloured snakes. Five species in south Indian forests.  Venom: Uncertain possibly could have an adverse effect on human beings. However due to the paucity of venom found within this snake little scientific study has been conducted. However since it belongs to the family Elaphidae and nearly all Elaphids are venomous immediate medical assistance should be sought if a bitten by this snake. 
Genus Naja -Only one species but three sub species. Naja naja naja- Binocellate or spectacled cobra (common cobra) present throughout India.  Naja naja kaouthia --Monocellate /Monocled or Bengal cobra—BengalAssam and in Andaman. Naja naja oxiana  - black cobra -North  west region.
Genus Ophiophagus . Only one species in Asia - Ophiophagus hannah,  the king cobra. The largest poisonous snake.

Subfamily Hydrophinae Sea snakes  - 20 species -13 present in the west coast
Family Viperidae. Vipers (Latin vivus = alive + parere = bring forth meaning viviparous nature) consists of two Sub-families (Viperinae and Crotalinae)- In the family total there are 224 species in 32 genera distributed in Americas, Africa and Eurasia. Seven Genera and 31 species in the area comprising Indian sub-continent China and Malay Peninsula. They are one of the most widely distributed snakes in the world. 
Subfamily - Viperinae . 
Genus Vipera (Daboia) -two species  V. lebetina (Blunt nosed viper-laventine viper) Kashmir.  V. russeli -Russel’s viper – throughout India  including  High altitude like  Munnar.  A large triangular head help in identification. Its body is stout and cylindrical. Venom extremely lethal causes heavy internal haemorrhages. Death is caused by heavy blood loss due to internal bleeding.  
Echis carinatus  A small venomous snake of arid regions . Has a short snout and rounded cheeks. Often light brown in colour with a lateral row of dark brown outlined mottles. Lethally venomous. Its venom destroys red blood cells, the walls of arteries and reduces blood pressure

Subfamily Crotalinae - Pit Vipers 
Genus Agkistrodon (Hypnale)- 2 species one in Himalayas other in south  (Hypnale hypnale
Genus Trimeresurus - 14 species - 4 in south Indian  forests  -T macrolepis( large scaled pit viper) 
T malabaricus (Malabar pit viper ), T strigatus (Horse shoe pit viper) , T. gramineus (bamboo pit viper )

Of the roughly 725 species of venomous snakes worldwide, only 250 are able to kill a human with one bite. In south India cobra, viper, king cobra and krait only are coming in this category.



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Indian Judiciary: Why medical termination of pregnancy ?



Indian Judiciary:Why medical termination of pregnancy?

Courtesy: Prasanth S.
http://secularcitizen.net


In an order of far-reaching implications, the Supreme Court of India on July 21 allowed a mentally-challenged orphan and rape victim to give birth to her child . In the process, the Supreme Court had also overturned a Punjab and Haryana High Court order dated July 17 2009, directing the termination of pregnancy of the 19-year-old girl, who was raped at a Nari Niketan (Women’s Home) run by the Chandigarh Administration.

The three-judge Bench headed by Chief Justice K G Balakrishnan said “We are not in favour of termination of pregnancy”, adding further that nature would give protection to them.
However, if to analyze an expert team’s report on the mental condition of the victim, which was read out in the court during the hearing, it painted a grim picture of the victim, as a mildly mentally challenged person who is unable to understand the concept of pregnancy and conception. Even her psychiatrist and gynaecologist had advised constant supervision of the victim, in their respective medical reports, to ensure her overall well being as she may not be able to take care of herself alone. In short, while the medical experts who have studied the victim had clearly stated that the woman is not fit mentally and physically to continue with the pregnancy, the rationale of law had surprisingly chosen to take just the opposite route,  for some reason.
Predictably, the judgment was welcomed with lots of silent criticisms, and ‘what if’ questions from the public at large, and Secular Citizen also joins them in analyzing the different aspects of the ruling, and its implications.
As someone having a third person perspective of the developments, Secular Citizen would like to ask the readers,
  •  What would be the fate of the child and the mother?
  •  Why should we have an MTP Act in place if a mentally challenged  rape victim is not bound by its purview?
The court order may be justifiable as a caveat to the misuse of Medical Termination of Pregnancy. However SECULAR CITIZEN smells serious prejudice to the legislative intent of  THE MEDICAL TERMINATION OF PREGNANCY ACT, 1971, in this decision.
The Medical Termination of Pregnancy Act, 1971 states that a pregnancy may be terminated by a registered medical practitioner of opinion, formed in good faith, if
(i) the continuance of the pregnancy would involve a risk to the life of the pregnant woman or of grave injury to her physical or mental health; or
(ii) there is a substantial risk that if the child were born, it would suffer from such physical or mental abnormalities to be seriously handicapped.
The Act further states that in determining whether the continuance of a pregnancy would involve such risk of injury to the health, account may be taken of the pregnant women’s actual or reasonable foreseeable environment. The Act also mentions that, if the pregnancy is caused by rape, the anguish caused by such pregnancy shall be presumed to constitute a grave injury to the mental health of the pregnant woman.
Now, taking a hard look at the facts we have, here, the rape victim is not only mentally challenged, but also the prospect of her ‘actual or reasonably foreseeable environment’ improving is slim. As per the medical reports, she is also in no state of mind to understand the concept of pregnancy and conception, leave alone raising the child. Also, there is no guarantee whatsoever that the child will be born in good health, and without any physical or mental abnormalities that would leave him/her handicapped for life. Further, we can’t say now if continuing the pregnancy would involve a risk to her life.
Shockingly, the woman is an orphan too. MTP Act says that , no pregnancy of a woman, who has not attained the age of eighteen years, or, who, having attained the age of eighteen years, is a lunatic, shall be terminated except with the consent in writing of her guardian.
The court might have taken refuge on its confidence on the social service organisations advocating for the rape victim’s rights. Can we expect the NGOs to act as the true guardian of the mother and child in letter and spirit ? then to what extent ?
Summing it all up, it appears to Secular Citizen that the best option would have been to terminate the pregnancy (considering the peculiar nature of this case),  rather than letting things escalate to more complexities and risks to the mother/child.
Ms.Rukmini Pillai, a social activist commented on this Article
In this particular judgement by the Honourable Supreme Court ‘anti- abortion’ has been given precedence to ‘The Right to Health’ of a mentally disabled Indian especially in her medical condition where the doctors have stated that this pregnancy endangers her life. Hard to believe that the Honourable Supreme Court fell for the argument given by the lawyer Bedi who is said to have stated that, ‘doesn’t she have the right to have her first known blood relation?’
The NGO which has fought for the rights of this woman are they a part of the ‘anti-abortion’ lobby of USA? What is the source of funding of this NGO? Or would Bedi, the lawyer be the hands-on mommy multi-tasking changing the new born nappies, feeding and burping the baby, changing the mentally challenged mothers’ menstrual pads etc.. so that the baby can grow up looking forward in knowing and bonding with another blood relation the rapist Dad or is it Dads?
Would rapist Dad/Dads be given rights in child-visitation USA style? With arguments like, ‘after all it is her Daddy/Daddys and we Indians are so forgiving’.
Honourable Supreme Court has stated that the unborn child sould be left ‘free’ in nature? So why is this particular NGO being entrusted with this mentally challenged woman at all? If she is not ‘safe’ in the Government run Nari Niketan probably she would be better off ’free’ on the streets.

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A randomized controlled trial on the efficacy of Neelidaladi kera in Dushivisha with signs and symptoms of Kitibha Kushta.



A randomized controlled trial on the efficacy of Neelidaladi kera in Dushivisha with signs and symptoms of Kitibha Kushta.


Dr.Bijaya Kumar Gupta
2006-2009
Under the guidance of
Dr. S.R. Manju, MD(Ay), D.A.T. &Dr. C. Vijayalakshmi, MD(Ay), D.A.T.
Abstract
At present context people are more exposed to various kinds of poisons in food as well as in environment which in turn leads to accumulation of Dushivisha inside the human body. As a result Dushivishaja twak vikaras are becoming more common. Kitibha Kushta is one of them. It has got similarity with certain varieties of psoriasis which affect nearly 3% of world population by influencing person`s personal and family life.

In the present scenario the traditional knowledge of health care is gaining momentum. It has been noticed, the skin diseases like Kitibha kushta is effectively managed by some of the traditional Visha Vaidya of Kerala by use of Neelidadi kera.So far no efforts has been made scientifically to evaluate the efficacy of this drug. Here is an attempt to find the efficacy of Neelidadi kera in Dushivisha with signs and symptoms Kitibha kushta.So that the traditional claim can be proved and established.

The study was designed as randomized controlled clinical trial. Patients were selected from O.P.D. of Department of Agadatantra and Government Ayurveda College, Thiruvananthapuram as per as the inclusion criteria. The 30 patients were distributed into study and control group by simple random sampling method. Out of that sixteen patients (study group) were received Patoladigana kashaya internally along with external application of Neelidadi kera and rest fourteen patients (control group) were given only Patoladigana kashaya internally without any external application for one month and were followed up for 15 days. Strict diet (pathya ahara and vihara) was advised during the study period. Both subjective and objective parameters along with PASI score and necessary routine Lab investigations were considered for clinical assessment. The data so obtained were statistically analyzed, tables, charts were drawn for interpretation and understanding the result.
Both the groups individually showed significant result on interpretation of data related to response of treatment. But among both, study group showed more significant results on assessment of clinical features like Kandu, Rooksha, Kinakhara sparsa, Parusha and also risk of any toxic effect was not observed during the study period. Neelidaladi kera is also found to be cost effective. Hence we come to a conclusion that the Neelidaladi kera is effective in subsiding Dushivisha with signs and symptoms of Kitibha kushta and worth using in practice.




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