- Divided anal plate.
- 21-23 keeled dorsal scale rows near midbody.
- One of the most distinctly patterned snakes in all of Texas, with its four dark longitudinal stripes contrasting greatly with its light gray colored background.
The upper two stripes are generally black with the two stripes found lower on the body either tan or light brown.
The belly is red or brown, with a median row of light spots found on the ventrals.
Some individuals may have three rows of these light spots on the belly.
Not a large snake, Nerodia clarkii typically measures between 38-76 cm (15-30 in).
Only found in the U.S., Nerodia clarkii is found along much of the Texas coastal wetland, as well as along the entire coastline of Louisiana, Mississippi, Alabama, and the majority of the Florida coast.
Being able to live in a harsh salty environment makes Nerodia clarkii atypical among the snakes of Texas. Drinking no salt water during its existence in the marshes, it aquires all of its water from its prey. These prey species include frogs and a wide variety of invertebrates, including shrimp, crabs, and crayfish. This non-venomous snake, also found on many of the grass-lined coastal barrier islands, is not considered aggressive, though it will definitely bite without hesitation if handled.
As many as 44 juvenile snakes may be born in a single litter. Nerodia clarkii is viviparous, giving birth to live young, which may be as long as 24.5 cm (9.5 in) when born.
The saltmarsh snake is aptly named as this snake is rarely found in fresh water environments, spending its entire life among the salt-grass marshes of the tidal wetlands.
The saltmarsh snake is not a protected species in Texas and can be legally collected with a hunting license.
In Texas, Nerodia clarkii is found along the coastline, from Corpus Christi eastward to the Texas-Louisiana border.