Crocodilians

What are general morphological characteristics of crocodilians?

-Elongated body w/powerful tails & limbs
-Long snouts
-Armored body
-Teeth sit in sockets
-4 chambered heart
-Pulmonary and systemic circulation

Bony plates called ___ located underneath the _____ scales

-Osetoderms

-Epidermal

______ separates the respiratory and buccal passageways

Secondary palate

What are behavioral characteristics of crocodilians?

-Nocturnal hunting strategy
-Oviparous-nest builders
-Unique dismemberment strategies
-Vocalization & visuals

Vocalization includes:

-Roars
-Grunts
-Cough
-Purrs from vocal cords

Low frequency sounds are made from:

Contractions of abdominal muscles

Crocodilians sensory system

-Enlarged olfactory processing region of brain
-Nictitating membrane
-Vertical pupils
-Tapetum lucidum
-Rods & Cones

Crocodilians locomotion:

-High walk
-Belly crawl
-Gallop

Crocodilian thermoregulation:

-Denning
-Ice response
-Basking

What are the 4 major morphological differences between Alligators & Crocodiles

1. Jaw shape
2. Teeth orientation w/closed mouth
3. Lingual salt glan
4. Dermal pressure receptors

Crocodylidae (14)

EX: Nile Crocodile
-Long snouth "V" or "A" shaped
-4th tooth exposed w/closed mouth
-Rest of teeth in pits w/closed mouth

Alligatoridae (8)

EX: American Alligator
-Snouth broad "U" or "C" shaped
-Opportunistic feeder
-"El Lagarto = Lizard
-4th tooth on bottom & pit in upper jaw

Gavialidae (1)

EX: Common Gharrial
-Long slender snout
-Piscivore
-Swallows fish head first
-Interlocking teeth