How to Identify the Mississippi Green Water Snake (Identification Guide)
Identify the Mississippi Green Water Snake by its heavy build, faint pattern of dark blotches on olive-green, and life in Gulf Coast wetlands.
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Key identifying features
The Mississippi Green Water Snake (Nerodia cyclopion) is a large, heavy-bodied water snake identified by its olive-green to brownish coloration overlaid with a faint pattern of dark, somewhat obscure blotches or crossbands, along with a row of small dark spots on the scales along the lower sides.
Coloration & pattern
The back typically appears dark olive, brown, or greenish, with darker blotches or bands that can be difficult to see against the background color, especially in dim light or on older individuals. A distinctive feature is a row of small dark spots along the lower sides at the point where the belly scales meet the body scales, which can help confirm identification when other pattern elements are unclear. The belly is pale yellow to cream, typically marked with dark, irregular spots or blotches.
Head, eyes & scales
The head is broad and blocky, fairly distinct from the neck, typical of heavy-bodied water snakes. Eyes are set high on the head with round pupils. Scales are strongly keeled, giving a rough-textured appearance to the body.
Size & body shape
Adults typically reach 30 to 45 inches (76-114 cm), with an occasional individual growing larger. The body is thick and muscular, with a moderately short, stout tail relative to overall length.
Range & habitat where you'll see it
This species is found along the Gulf Coastal Plain, including parts of Louisiana, Mississippi, and adjacent states, inhabiting swamps, bayous, lakes, and slow-moving rivers with abundant vegetation. It is frequently associated with cypress swamps and other heavily vegetated wetland habitats.
How to tell it apart from look-alikes
The Mississippi Green Water Snake closely resembles the Florida Green Water Snake but occupies a different, largely non-overlapping range along the Gulf Coast rather than peninsular Florida, and it tends to show a somewhat more visible dark blotched pattern along with the characteristic row of small spots along the lower sides. Like its Florida relative, it is sometimes mistaken for a venomous cottonmouth, but its round pupils and less triangular head shape help distinguish it from that species.
Frequently asked questions
What pattern feature helps confirm a Mississippi Green Water Snake?
A row of small dark spots along the lower sides where the belly scales meet the body scales, in addition to faint dark blotching on an olive-green background.
How does it differ from the Florida Green Water Snake?
The two are similar, but the Mississippi Green Water Snake occurs along the Gulf Coastal Plain rather than peninsular Florida and often shows a slightly more visible blotched pattern.
Where does this snake typically live?
In swamps, bayous, lakes, and slow rivers with dense vegetation along the Gulf Coastal Plain, including Louisiana and Mississippi.
Is this snake often confused with a cottonmouth?
Yes, due to its heavy body, but round pupils and a less triangular head shape distinguish it from the venomous cottonmouth.
Is the Mississippi Green Water Snake venomous?
No, it is nonvenomous and harmless to humans.