Family : HOMALOPSIDAE
Species : Hypsiscopus plumbea
Maximum Size : 48 cm

The Grey Water Snake Hypsiscopus plumbea is one of the most widespread of all asian water snakes. The species is also known as Boie’s Mud Snake and Plumbeous Water Snake. It was formerly referred to as Enhydris plumbea, but was renamed in 2014 (Murphy et al, 2014).

The term plumbea or 'plumbeous' means 'like lead', which refers to the grey colour on the upperside of its body, however in some populations its upperside may be olive-grey, dark brown or greenish. There may be small, dark spots along the vertebral line. Its underside is yellow, sometimes with black spots.

Its body is robust and cylindrical in cross-section, its short head is barely wider than its body, and its tail is short. Its eyes are situated on top of its head.

The species typically inhabits still or slow-moving shallow water bodies such as rice paddies, open swamps, marshes, streams and ditches. The specimen shown here was found on a manmade structure at the margin of the Nam Song River in Laos.

It is mainly nocturnal in habits.

On mainland Southeast Asia the Grey Water Snake occurs in Myanmar, Indochina (Cambodia, Laos, Vietnam), Thailand and Peninsular Malaysia. Outside the region it occurs in parts of India (Andaman Islands) and southern China (including Taiwan). In insular Southeast Asia it occurs on the islands of Sumatra, Borneo, Java,  Bali, Sulawesi and possibly other islands further east.

Fig 1 : Fully grown specimen resting on a manmade structure at the edge of the Nam Song River, Vang Vieng, Laos.

Fig 2 : View of the Nam Song River at Vang Vieng, Laos. This water body appears to be rather wider and faster flowing than typical habitats for this species. It is possible the snake was swept downstream by strong currents.

Fig 3 : Close-up of the left flank, showing the strong demarcation between its grey upperside and yellow underside.

Fig 4 : Example with olive-green upper body, from Phetchaburi province, Thailand.

Figs 1 to 3 photos thanks to Timothy Pwee.
Fig 4 photo thanks to Charles Currin.


References :

Das, I., 2010. A Field Guide to the Reptiles of South-east Asia. New Holland Publishers (UK) Ltd.

Murphy, J.C. & Voris, H.K. 2014. A Checklist and Key to the Homalopsid Snakes (Reptilia, Squamata, Serpentes), with the Description of New Genera. Fieldiana: Life and  Earth Sciences (8): 1–43