How to Identify Stokes's Sea Snake (Identification Guide)
Stokes's Sea Snake is a robust, heavy-bodied sea snake identified by its thick build, pale and dark blotched or banded pattern, and rough-textured scales for a sea snake.
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Key identifying features
Stokes's Sea Snake (Hydrophis stokesii) is one of the most heavily built sea snakes, notable for its unusually thick, robust body compared to most other sea snakes, which tend to be slender. It has a small head relative to its stout body and the typical flattened, paddle-shaped tail of true sea snakes.
Coloration & pattern
The body typically shows a pattern of dark blotches, bands, or diamond-like markings over a paler gray, cream, or yellowish background. The pattern can appear bold and irregular, sometimes forming broken bands rather than continuous rings. This contrasts with the more uniformly banded look of species such as sea kraits.
Head, eyes & scales
The head is small and only modestly wider than the neck, appearing almost disproportionately small compared to the very thick body. Eyes are small with round pupils. Unlike most smooth-scaled sea snakes, Stokes's Sea Snake has noticeably rough, keeled body scales, an unusual trait among sea snakes and a helpful identification feature.
Size & body shape
Adults can reach up to about 1.5 meters and are distinguished by an exceptionally thick, heavy body, among the stoutest of all sea snakes relative to length. The tail is flattened into a paddle shape typical of fully marine sea snakes.
Range & habitat where you'll see it
This species is found in coastal and reef waters of the tropical Indo-Pacific, including northern Australian waters and nearby regions. It is fully aquatic, spending its entire life in the sea, often in turbid coastal waters as well as clearer reef habitats.
How to tell it apart from look-alikes
The combination of an unusually thick, heavy body, small head, and rough keeled scales readily separates Stokes's Sea Snake from most other sea snakes, which are typically slender with smooth scales. Its irregular blotched pattern also differs from the neat, continuous banding of sea kraits. This distinctive rough scalation paired with a stout body shape is one of the most reliable ways to identify the species at a glance.
Frequently asked questions
What makes Stokes's Sea Snake's body unusual among sea snakes?
It is exceptionally thick and heavy-bodied compared to most sea snakes, which tend to have slender bodies.
Are its scales smooth like other sea snakes?
No, it has noticeably rough, keeled scales, which is unusual among sea snakes and a helpful identification clue.
What pattern does it show?
Dark blotches, bands, or diamond-like markings over a paler gray, cream, or yellowish background, often irregular rather than forming neat continuous rings.
How large does this species get?
Adults can reach up to about 1.5 meters, with an unusually thick, heavy body for a sea snake.
Where does Stokes's Sea Snake live?
In coastal and reef waters of the tropical Indo-Pacific, including northern Australian waters.