Spine-tailed sea snake
Holotype: BMNH 19188.8.131.52 (formerly BMNH iii.10.1a and BMNH 18184.108.40.206).
Type-locality: Indian Ocean.
Marine waters of Thailand, Kampuchea, the Indo-Malayan Archipelago, and northern Australia (northwestern Western Australia eastward to the Great Barrier Reef). South China Sea, Gulf of Thailand.
Distribution: Australia (North Territory, Queensland, West Australia), South China Sea, Gulf of Thailand, Indonesia, W Malaysia, Vietnam, New Guinea.
Type locality: Indian Ocean
Habitat and Ecology
Water temperature and chemistry ranges based on 1 sample.
Depth range (m): 10.7 - 50.4
Temperature range (°C): 24.782 - 24.782
Nitrate (umol/L): 1.001 - 1.001
Salinity (PPS): 35.354 - 35.354
Oxygen (ml/l): 4.657 - 4.657
Phosphate (umol/l): 0.135 - 0.135
Silicate (umol/l): 1.140 - 1.140
Depth range (m): 10.7 - 50.4
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.
IUCN Red List Assessment
Red List Category
Red List Criteria
This species was seasonally abundant as trawler bycatch in western Malaysia in 1989 (Stuebing and Voris 1990). This is also the case in the Gulf of Carpentaria (D. Milton pers. comm. 2009). Also captured in the eastern prawn trawl fisheries in Australia (makes up 2 % of the sea snake catch) (Courtney et al. 2010). In Madura Straits (East Java, Indonesia), this species comprised 14 out of 256 bycaught snakes collected over ten days in June 2010 (K. Sanders and Mumpuni pers. comms.).
Sea snakes are protected in Australia since their addition to the ‘Listed Marine Species’ by the Department of Environment and Water Resources in 2000. They are protected in Australia under the Environment Protection Biodiversity and Conservation Act 1999. This requires that all Australian industries interacting with protected species, directly or indirectly, demonstrate sustainability for the species impacted by their activities (Milton et al. 2008). The Australian Fisheries Management Act 1991 requires fishing efforts to avoid captures of threatened and protected species such as sea snakes.
A conservation recommendation is to reduce the number of individuals caught as bycatch in the prawn trawl fishery using appropriate exclusion devices within nets (Courtney et al. 2010).
Spine-tailed Seasnake Aipysurus eydouxii, also known as the Marbled Seasnake is a species of sea snake. This snake is unusual amongst sea snakes in that it feeds exclusively on fish eggs. Due to this ecological change, this species has lost its fangs and the venom glands are almost entirely atrophied. The scientific name commemorates the French naturalist Joseph Fortuné Théodore Eydoux.
This species is found in Western Australia, Northern Territory, Queensland, the South China Sea, the Gulf of Thailand, Indonesia, Peninsular Malaysia, Vietnam, and New Guinea inhabiting shallow bays and estuaries.
Only one other species of sea snake, Emydocephalus annulatus, shares A. eydouxii’s eggs only diet. The origin of the eggs only diet of A. eydouxii results from a genetic mutation that impacted the snakes’ ability to hunt and feed. Due to a dinucleotide deletion in the 3FTx gene, toxicity of the snakes’ venom was greatly reduced. This decrease in toxicity negatively impacted the snake’s ability to hunt and capture fish for sustenance, leading to a subsequent change in diet from fish to fish eggs. The snake has also evolved several adaptations to their new feeding habits including strong throat musculature; consolidation of lip scales, reduction and loss of teeth, and greatly reduced body size.
- Kharin, V. E. 1981 A review of sea snakes of the genus Aipysurus (Serpentes, Hydrophiidae) Zoological Zhurnal 60 (2): 257-264
- Li, M., Fry, B.G. & Kini, R.M. (2005) Putting the brakes on snake venom evolution: The Unique Molecular Evolutionary Patterns of Aipysurus eydouxii (Marbled Sea Snake) Phospholipase A2 Toxins. Molecular Biology and Evolution 2005 22(4):934-941
- Li, M., Fry, B.G. & Kini, R. M. (2005) Eggs-Only Diet: Its Implications for the Toxin Profile Changes and Ecology of the Marbled Sea Snake (Aipysurus eydouxii). Journal of Mol. Evo. 60:81-89.
- Voris, H. K. & Voris, H. H. (1983) Feeding strategies in marine snakes: an analysis of evolutionary, morphological, behavioral and ecological relationships. Amer. Zool. 23:411-425.