Port Darwin Sea Snake (Hydrelaps darwiniensis) deceased beach specimen.
Elapidae
Port Darwin Sea Snake
Hydrelaps darwiniensis
Port Darwin Sea Snake is a small mangrove and coastal sea snake with a light grey or yellowish body and many dark bands.
Venomous
Identification and appearance
The museum revision describes a small snake of fairly uniform thickness with a moderately large head and many dark body bands. Its specimen descriptions give a light grey or yellowish background.
Other names
Black-ringed Mangrove Sea Snake, Black-ringed Sea Snake, Darwin's Sea Snake
Typical length
The 1974 museum account describes specimens up to 52.5 cm long; this does not establish a typical adult size interval.
Head appearance
moderately large head, bluish grey head
Key identification features
- Small, fairly uniform body thickness
- Light grey or yellowish ground colour
- Many dark body bands with blackened adjoining ventrals
Where it is found
Northern Australian coastal waters and mangrove areas, including the Kimberley and north-west coasts of Western Australia, the Northern Territory and Queensland; the type locality is Port Darwin.
Activity
Mostly marine or semi-aquatic, with records from mangrove and coastal settings.
Diet
It has been observed feeding on fish in narrow mangrove creeks as tides rise and fall.
Reproduction
Live-bearing.
Medical significance
Treat any suspected bite as an emergency. Call 000 and follow Australian snakebite first aid; do not wait for identification.
What to do if you encounter one
Keep clear in mangroves, tidal flats or water and do not attempt to catch or photograph closely.
Similar-looking snakes
The distinguishing preocular character is a specimen-level feature. Do not approach a banded coastal snake to inspect its head scales.
Taxonomy notes
Originally described from Port Darwin; the current genus is Hydrelaps.
Sources checked
- Smith 1974, Western Australian Museum — Sea snakes of Western Australia (2026-09-26)
- The Reptile Database — Hydrelaps darwiniensis (2026-09-26)
- BHL — Observations of the Port Darwin Sea Snake (2026-09-26)
- ANZCOR — Australian snake bite first aid (2026-09-26)
- Somaweera et al. 2023 — Feeding observations in aquatic snakes (2026-09-26)
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A profile is a guide, not a reason to approach or handle a snake.