Description: The color pattern consists of a brownish, brownish-yellow, brownish-gray or olive ground color, overlaid with a series of 24–35 dark brown to black diamonds with slightly lighter centers. Each of these diamond-shaped blotches is outlined with a row of cream or yellowish scales. Posteriorly, the diamond shapes become more like crossbands and are followed by 5–10 bands around the tail. The belly is a yellowish or cream-colored, with diffused, dark mottling along the sides. The head has a dark postocular stripe that extends from behind the eye backwards and downwards to the lip; the back of the stripe touches the angle of the mouth. Anteriorly and posteriorly, the postocular stripe is bordered by distinct white or yellow stripes. The rattle at the end of their tail is made of hard, loosely attached, hollow segments which break off frequently and are completely replaced when the snake sheds.

Specimens are rarely found over 6 feet in length. Lengths of 3.5 to 5.5 feet, and 2.75 to 6 feet. The average body mass is roughly 5.1 lbs.

Habitat: The eastern diamondback rattlesnake inhabits upland dry pine forest, pine and palmetto flatwoods, sandhills and coastal maritime hammocks, longleaf pine/turkey oak habitats, grass-sedge marshes and swamp forest, cypress swamps, mesic hammocks, sandy mixed woodlands, xeric hammocks, and salt marshes, as well as wet prairies during dry periods. In many areas, it seems to use burrows made by gophers and gopher tortoises during the summer and winter.

Range: The eastern diamondback rattlesnake is found in the Southeastern United States from southeastern North Carolina, south along the coastal plain through peninsular Florida to the Florida Keys, and west along the Gulf Coast through southern Alabama and Mississippi to southeastern Louisiana. The original description for the species does not include a type locality, although it has been proposed it is restricted to "Charleston, South Carolina" (USA).

Found in these States: AL | FL | GA | LA | MS | NC | SC

Venom: In proportion to its length, it has the longest fangs of any rattlesnake species, with calculations leading one to expect an 8 foot specimen would have fangs with a total length of over 1 inch. For comparison, a 5 foot specimen had fangs measuring 2/3 inches in length. It has a very high venom yield, an average of 400–450 mg, with a maximum of 858–1,000 mg. Brown gives an average venom yield of 410 mg (dried venom), along with LD50 values of 1.3–2.4 mg/kg IV, 1.7–3.0 mg/kg IP and 14.5–10 mg/kg SC for toxicity. The estimated human lethal dose is 100–150 mg.

The venom contains a thrombin-like enzyme, "crotalase", capable of clotting fibrinogen, leading to the secondary activation of plasminogen from endothelial cells. Although the venom does not activate platelets, the production of fibrin strands can result in a reduced platelet count, as well as the hemolysis of red blood cells. Even with this defibrination, however, clinically significant bleeding is uncommon. Nevertheless, the venom does exhibit high hemorrhagic activity. It also contains a low-molecular-weight basic peptide that impedes neuromuscular transmission and can in theory lead to cardiac failure. This peptide is similar to crotamine from C. durrisus terrificus, and makes up 2–8% of the protein found in the venom. In general, the venom can be described as highly necrotizing, mildly proteolytic and containing a large phosphodiesterase fraction. It stimulates the release of bradykinin that can result in severe pain, as well as profound, transient hypotension.

CroFab, ANAVIP, and Wyeth's ACP are effective antivenins against bites from this species, although massive doses may be needed to manage severe cases of envenomation. Generally, ACP is very effective at countering the defibrination syndrome that is often seen, but may do little for low platelet counts. Wyeth's ACP is no longer being manufactured.

Diet: The eastern diamondback rattlesnake forages actively or lies in ambush for small mammals, especially rabbits and rice rats (Oryzomys). The diet also includes birds. Prey is struck and released, after which the snake follows the scent trail left by the dying prey.

Because of their large size, adults have no problem eating prey as large as fully grown cottontail rabbits. As the juveniles are capable of swallowing adult mice, they do not often resort to eating slimmer prey, such as lizards. In fact, eastern cottontails and marsh rabbits (Sylvilagus) form the bulk of the diet in most parts of Florida. Squirrels, rats, and mice are also eaten, along with birds such as towhees and bobwhite quail. Other prey that have been reported include a king rail, a young wild turkey, and a mother woodpecker along with four of her eggs. It also eats large insects

Reproduction: Rattlesnakes, including the eastern diamondback, are ovoviviparous.[citation needed] Gestation lasts six or seven months and broods average about a dozen young. However, the young only stay with the mother 10–20 days before they set off on their own to hunt and find cover. Females give birth to between 7 and 21 young at a time, usually between July and early October. Neonates are 12–14 inches in length and are similar in appearance to the adults, except for having only a small button instead of a rattle on the tip of their tails.

Status: Listed as Least Concern in view of its wide distribution, presumed large population, and because it is unlikely to be declining fast enough to qualify for listing in a more threatened category.

Taxonomy: