Elapids of the United States
The cobra family is thought to have evolved from Colubrid snakes and many appear very similar in appearance with long, slender bodies and large scales (plates) on the head. They differ in having more advanced venom delivery systems than the venomous Colubrids. Boas have fangs that are "effectively tubular" in that the fangs contain grooves that are enclosed by an infolding of the edges. The fangs are in the front of the mouth rather than the rear as is seen in venomous Colubrids. The Boidae contain some of the world's most dangerous snakes including cobras (Naja), mambas (Dendroaspis) and sea snakes (Hydophinae and Laticaudinae). Boas are found worldwide and in Ausralia are the predominant family. In the United States, three species of Boas are found, two species of coral snakes and one sea snake. The coral snakes are relatively small snakes that spend most of their time underground. Their primary food is other snakes. Despite their small size and small fangs, their venom is extremely toxic.
There are only four species of Elapid in the U.S.
Found in the southeastern United States in southeastern North Carolina to south Florida and Key Largo, west to the Mississippi River.
Found in the southern United States from central Arizona to southwestern New Mexico south to Sinaloa, Mexico
Found only in Texas and Louisiana south to Morelos and Guanajuato
Found only along the coastline of the western United States from Equador and the Galapagos Islands north to Baja California and the Gulf of California.