Crocodilians and Turtles part 1b (practical 4)

Crocodylia

This order is full of top carnivores that have large bodies covered in osteoderms. They have long toothy snouts.

Alligatoridae

This family is found in both North and South America as well as China. They have broad snouts and robust teeth. The lower teeth are "hidden" when the mouth is closed.

American Alligator/ Alligator Mississippiensis

This species is found in the southeastern U.S. It has a broad, rounded snout. It is the only freeze tolerant crocodilian and it is young are dark with yellow bands or rings.

Spectacled Caiman/ Caiman crocodilus

This species is native to Central and South America. It is olive colored with darker blotches. It gets its name from its bony ridge between its eyes.

Dwarf Caiman/ Paleosuchus palpebrosus

This species is native to northern and central South America. It is smaller than its relatives and it is overall dark and has a row of large blotches on its lower jaw.

Crocodylidae

This family is found worldwide. Its members have long, narrow and triangular snouts. Its members have large body sizes with robust teeth. The 4th tooth on the lower jaw fits into the notch and is visible when jaws closed.

Nile Crocodile/Crocodylus niloticus

This species is native to Africa. Its members have long, narrow and triangular snouts. Its members have large body sizes with robust teeth. The 4th tooth on the lower jaw fits into the notch and is visible when jaws closed.

Gavialidae

This family's members are found in India and Borneo. The members are large with very narrow snouts with needle-like teeth. The teeth of the lower jaw are visible when the mouth is closed.

Gavial/ Gavialis gangeticus

This species is found in India and Borneo. The members are large with very narrow snouts with needle-like teeth. The teeth of the lower jaw are visible when the mouth is closed.

Testudines

This order of animals has ribs modified to form a carapace and have a highly modified body plan.

Chelidae

This family of turtles are found in Australia, New Guinea, Indonesia, and South America. They have side necks and have a intergular, but the nuchals are variable. They have 12 marginals.

Mata Mata/ Chelus fimbratus

This species of turtle is found in South America. They have side necks and have a intergular, but the nuchals are variable. They have 12 marginals. They look like leaf litter and suction feed.

Cheloniidae

This family of turtles is found worldwide. They have a front neck. The plastrodon is unhinged. The limbs are modified into flippers and their are 4-9 pairs of costals present. They also have a nuchal present.

Green Turtle/ Chelonia mydas

This species of turtle is found worldwide. They have a front neck. The plastron is unhinged. The limbs are modified into flippers and there are 4-9 pairs of costals present. They also have a nuchal present. They only have 1 pair of prefrontals between the

Platysternidae

This family of turtles is found in China. They have front necks. They have a full bony shell and a very long tail. Their plastron usually is found with 12 scutes, a very flattened shell with smooth rear margin. They also have a very large head.

Bighead Turtle/ Platysternon megacephalum

This species of turtle is found in China. They have front necks. They have a full bony shell and a very long tail. Their plastron usually is found with 12 scutes, a very flattened shell with smooth rear margin. They also have a very large head.

Chelydridae

This family of turtles is found in North America to Ecuador, but is mostly seen in the Mississippi River Drainage. It has a front neck and the Plastron is reduced and the bridge is very narrow. The rear edge of the carapace is serrated and it's plastron u

Common Snapping Turtle/ Chelydra serpentina

This species of turtle has a single row of 12 marginals on each side of its carapace. Its tail has 2 rows of large scales underneath and there are generally few tubercles on the neck and chin.

Alligator Snapping Turtle/ Macrochelys temminckii

This species of turtle has 12 normal marginals along each side of the carapace with a row of 4 supramarginals above M5-8. It also has many tubercles on the neck and chin.

Kinosternidae

This family of turtles is found in North and South America. They have front necks. Its members have full bony shells and their carapaces are smooth with a smooth rear margin. They have a normal plastron with broad bridges. Members of this family have 11 p

Striped Mud Turtle/ Kinosternon baurii

This species of turtle has 2 plastral hinges. It often has 2 light lines on each side of its head and its 3 longitudinal light lines on the carapace.

Yellow Mud Turtle/ Kinosternon flavescens

This species of turtle has 2 plastral hinges. Its M9 and M10 both extends upward. Its plastron is usually pale yellow there is no keel on the carapace.

Mexican Mud Turtle/ Kinosternon hirtipes

This species of turtle has 2 plastral hinges. Its M9 does not extend upward and its M10 is not distinctly higher than M9. Its head and neck have fine reticulations and the shell often has a posterior keel.

Eastern Mud Turtle/ Kinosternon subrubrum

This species of turtle has 2 plastral hinges. It has a face that often has distinct light lines from the eye to the neck. Its M9 doesn't extend upward and the M10 is not distinctly higher than M9. Its 1st vertebral does not contact the 2nd marginal.

Razorback Musk Turtle/ Sternotherus carinatus

This species has no plastral hinges. It does not have light facial stripes and it has a prominent mid-dorsal keel. Its gulars are essentially absent.

Common Musk Turtle/ Sternotherus odoratus

This species has no plastral hinges. It has 2 light stripes on each side of its face. Its shell is domed (may have 3 faint keels when young). Its gulars are sometimes absent.

Trionychidae

This family is found in North America, Africa, and Asia. Its members have front necks. Its members' shells lack epidermal scutes = carapace leathery and pliable. It has a slender, tubular nose and an extremely long neck.

Florida Softshell/ Apalone ferox

This species has a softshell with flattened tubercles in more than one row along the anterior the carapace. It often has a marginal ridge present.

Spiny Softshell/ Apalone spinifera

This species has a softshell with spines or conical projections in a single row along the anterior edge of the carapace. It has no marginal ridge on the carapace.