N. r. blanchardi (Clay, 1938) N. r. rhombifera (Hallowell, 1852) N. r. werleri (Conant, 1953) Nerodia rhombifer, commonly known as the diamondback water snake, is a species of nonvenomous natricine colubrid endemic to the central United States and northern Mexico.
In typical counter-colored fashion, the underside is generally a yellow or lighter brown color, often with black blotching.
[3] Adult males have multiple papillae (tubercles) on the under surface of the chin, which are not found on any other species of snake in the United States.
Its bite is known to be quite painful due to its sharp teeth meant to keep hold of slippery fish, as well as the slight hemotoxin in its saliva[citation needed] that causes increased bleeding.
This defensive behavior is frequently misinterpreted as aggression and often leads to its being mistaken for the venomous cottonmouth (Agkistrodon piscivorus), with which it does share habitat in some places.
The diamondback water snake is found in the central United States, predominantly along the Mississippi River valley, but its range extends beyond that.
It ranges within the states of Texas, Oklahoma, Kansas, Iowa, Louisiana, Arkansas, Missouri, Illinois, Indiana, Tennessee, Mississippi, Georgia, and Alabama.
There have been no confirmed observations of watersnakes at Lafayette Reservoir since late 1999, but sightings are occasionally reported, and the population may still continue to present in low numbers.
Adults breed in the spring, and gravid females give birth in the late summer or early fall.