1. Presentation by-
Deepak Rawal
Assistant Professor
Mohanlal Sukhadia University
Udaipur India

2. REPTILIA CLASSIFICATION

3. General characters
• Reptiles means creeping
• Limbs are clawed when present
• Study of reptiles is called herpetology
• Cold- blooded(poikilothermic)
• Exoskeleton of horny scales,scutes or bony plates
• Skin dry,cornified and non glandular
• Skull is monocondylic
• T-shaped interclavicle present
• Heart with 2 auricle and incompletely divide ventricle(3.5 chambers) except crocodiles
whose have 4 chambers
• R.B.C. oval and nucleated
• 3-chambered Cloaca present
• Uricotelic excretion
• Metanephric kidney
• Cranial nerves 12 pairs (except snakes which have 10 pairs)
• Sexual dimorphism present
• Fertilisation internal
• Eggs are cleidoic(large yolky eggs with calcareous shell)
• No larval stage
• Amniotes(all 4extra-embryonic membranes present)

4. Classification of only living reptiles
Class-Reptilia
subclass- Subclass-
Anapsida Diapsida
Order-
Order-Chelonia
Rhynchocephalia
Order-Squamata
Order-Crocodilia

6. Amniotic cleidoic egg

7. Types of teeth in reptiles

8. • Chelone means turtles
ORDER-CHELONIA
• Anapsid skull
• Body enclosed in a dorsal carapace and ventral plastron made of dermal bony plates
• Teeth absent jaws with horny beaks
• Single nasal opening
• Limbs of aquatic forms modified into paddles
• Short tail
• Single intromittent organ in male
• Sternum is absent
• Cloacal respiration found
• Longest lifespan
• marine turtles;freshwater terrapins and terrestrial tortoises
• Example- Chelone

9. ORDER-RHYNCHOCEPHALIA
• Single species sphenodon punctatum(tuatara) of new
zealand
• Skull diapsid
• Skin with scales and mid dorsal row of spine
• Vestigial pineal eye present in parietal foramen
• No copulatory organ in male
• Teeth acrodont
• Eggs hatches in 13 months
• Living fossils

10. ORDER-CROCODILIA
• aquatic reptiles
• Sternum present
• Skin thick with bony plates and scutes
• Limbs are clawed and webbed
• Males have one intromittent organ
• Teeth thecodont
• Heart completely 4 chambered
• Examples-gharial, alligator and crocodile
• Example- Crocodylus

11. ORDER-SQUAMATA
• Lizards and snakes
• Suborder lacertilia/sauria- lizards
• Suborder ophidia/serpentina- snakes
• Bifid tongue in most
• Jacobson organ (gustatory and and olfatory organ) present in
the roof of mouth
• horny epidermal scales
• Teeth acrodont or pleurodont
• Male with double copulatory organ(hemipenes)
• Example- Calotes (garden lizard)

12. JACOBSON ORGAN

13. Difference between lizards and snakes
LIZARDS SNAKES
1. Limbs present usually Limbs absent usually
2. Sternum present Srernum absent
3. Eyelids are movable Eyelids are immovable
4. Tympanum is present Tympanum is absent
5. Both lungs well developed Left lung usually reduced
6. Nictitating membrane present Nictitating membrane absent

14. Dinosaurs
• Dino-terrible; saurus-lizard
• They were diapsid
• Extict reptiles
• Thecodont teeth
• Clavicle and interclavicle absent
• Double headed ribs
• Extinct due to meteor attack on earth
• Dinosaurs were aquatic,aerial and terrestial
• They was present on earth on jurassic epoch of mesozoic era

15. IDENTIFICATION OF POISONOUS
AND NON-POISONOUS SNAKES

16. E.g.- Hydrophis
E.g- Pythons
E.g- Rat snakes
E.g- Pitless vipers E.g- Pit vipers
E.g- Kraits
E.g- Cobras

17. Scales in head region of snakes

21. POISONOUS AND NON-POISONOUS
SNAKES OF INDIA
POISONOUS NON-POISONOUS
HAEMOTOXIC • Python- Python regis
• Pit vipers; examples- Lechesis,
Ancistrodon • boas
• Pitless vipers;Daboia russeli (russell • Blind snake-Typhlops
viper)
Echis carinatus (saw scale viper) • Rat snake(dhaman)- Ptyas
NEUROTOXIC mucosa
• Indian cobra-Naja naja(spectacle
cobra)
• King cobra – Ophiophagus hanna
• Comman krait- Bungarus caeruleus
• Sea snake- Hydrophis obscurus
• Coral snake- Callophis

22. POISONOUS SNAKES OF INDIA
The common krait.
Indian Cobra Russell's viper.
The saw-scaled viper.

23. SNAKE VENOM
• There are about more than 300 species of snakes in INDIA out of
which only 20 % are poisonous and 80 % are non-poisonous.
• Fangs are modified maxillary teeth’s
• Poison glands are modified parotid salivary glands
• Snake venom is modified saliva used by snakes to immobilize and
digest prey or to serve as a defence mechanism against a predator
• Venom is mixture of enzymes and proteins
• It is tasteless, odourless and acidic in nature
• It is fatal only when mixed in blood
• Haemotoxin affect circulatory system by damaging blood vessels
and haemorrhage
• Neurotoxin affect nervous system and cause death due to paralysis
of respiratory muscles and asphyxia

25. Medicinal uses of venom
•In Drug researches
•Have antibacterial applications
•To cure Excessive bleeding: some of the enzymes in venom
has been found to clot blood which stop excessive bleeding.
•To cure Stroke: Pit Viper venom has potential for breaking
blood clots and treating stroke victims.
•To cure Neurological diseases :Enzymes from cobra venom
may be cures for Parkinson's disease and Alzheimer's disease.
•To cure Cancer (various types) : An enzyme derived from
copperhead venom could be used to treatment for breast
cancer.
•To prevent Aging: some are even used in a commercial
wrinkle cream
•To cure arthritis
•To cure paralysis

26. Antivenom/Antivenin
• Antivenom is a antibody (ig G) for snake venom
• It is a protein
• It is prepared by hyperimmunising horses against venoms
of snake
• It neutralises the free, unbound venom & also dissociates
the bound toxin
• If venom is obtained from a single species, then it is
called monovalent antivenom. If the antivenom obtained
from two or more species of snakes, then it is
called polyvalent.
• In India Antivenin is produced at the Haffkin’s Institute at
Bombay and Central Research Institute at Himachal
Pradesh.