American Alligator

The average size for an adult female American alligator is 8.2 feet (2.6 m), and the average size for a male is 11.2 feet (3.4 m). Exceptionally large males can reach a weight of nearly half a ton or 1,000 pounds.
Both males and females have an "armored" body with a muscular flat tail. The skin on the back is armored with embedded bony plates called osteoderms or scutes. They have four short legs; the front legs have five toes while the back legs have four toes.
Alligators have a long snout with upward facing nostrils at the end; this lets them breathe while the rest of the body is underwater. The young can be distinguished from adults by the bright yellow stripes on the tail; adults have dark stripes on the tail.

http://nationalzoo.si.edu/animals/reptilesamphibians/facts/factsheets/a…