Fig. 1-6. Asthenodipsas laevis specimen (ZRC 2.7079) from Old Upper Thomson Road.
Fig. 1. Dorsal view of entire snake.
Fig. 2. Side view of colour pattern and scalation at mid-body.
Fig. 3. Dorso-lateral view of posterior including tail.
Fig. 4. Close-up of the underside of the tail showing the paired subcaudal scales.
Fig. 5. Side view of crushed neck and head.
Fig. 6. Underside of head, showing asymmetrical chin shields and absence of median furrow typical of the Pareatidae.
Photographs by Nick Baker

Second record of the Smooth Slug Snake (Asthenodipsas laevis) in Singapore

Location, date and time: Singapore Island, Old Upper Thomson Road, near gate to Upper Peirce Reservoir Park; 8 January 2014, 0950 hrs.

Observation: An example of 33.6 cm total length (Fig. 1-6) was found on the road. It had clearly been run over by a vehicle – the head, body and tail were all crushed to varying degrees, and had become dessicated under the sun, such that there was no smell of decay.

Scale characteristics observed of the specimen are: 1 loreal; 6 supralabials with 3, 4 and 5 in contact with the eye, and the 6th nearly equal in length to the others; no preocular; 15 dorsals; 161 ventrals; 52 pairs of subcaudals; anal not divided.

Remarks: The present example may have been run over by a vehicle the previous evening, or even a few days before due to its dessicated state. It may have ventured onto the tarmac for warmth, or attempted to cross the road from one patch of secondary forest to another. The specimen has been deposited in the Zoological Reference Collection of the Lee Kong Chian Natural History Museum at the National University of Singapore as ZRC 2.7079. Scale counts taken from the specimen agree with the information provided by Tweedie (1983: 38, as Pareas laevis) and Manthey & Grossmann (1997: 308, as Pareas laevis).

This is the second specimen of Aesthenodipsas laevis known from Singapore. It has been mentioned by Tan (2014) but without detailed information and the specimen was not illustrated. Lim (2009) found the first Singapore specimen in 1978 in a drain within the compound of the Singapore Zoo. Unfortunately that specimen, although kept, was misplaced and subsequently lost. The location of this second specimen lies some 4.2 km south-east from the first.

The Smooth Slug Snake specializes in eating terrestrial molluscs and is known to attain a maximum size of about 60 cm. It is distributed in the Malay Peninsula, Sumatra, Borneo and Java (Manthey & Grossmann, 1997: 308, as Pareas laevis). Based on its size, the present specimen appears to be a young individual. Given that the species is found in territories around Singapore, it is most likely to be native there. We propose that its status in Singapore be updated from ‘indeterminate’ (Baker & Lim, 2012: 171) to ‘extant indigenous’.


  • References:
    Baker, N. & K. K. P. Lim, 2012. Wild Animals of Singapore. A Photographic Guide to Mammals, Reptiles, Amphibians and Freshwater Fishes. Updated edition. Draco Publishing and Nature Society (Singapore), Singapore. 180 pp.
  • Lim, F. L. K., 2009. Asthenodipsas laevis (Reptilia: Squamata: Pareatidae), a snake record for Singapore that was almost forgotten. Nature in Singapore. 2: 463–465.
  • Manthey, U. & W. Grossmann, 1997. Amphibien & Reptilien Sudostasiens. Natur und Tier – Verlag, Berlin. 512 pp.
  • Tan, A., 2014. Researchers find two snake species new to Singapore. The Straits Times. Tuesday, 23 December 2014: Home, B2.
  • Tweedie, M. W. F., 1983. The Snakes of Malaya. Third edition. Singapore National Printers (Pte) Ltd. 167 pp.

Source: Singapore Biodiversity Records 2014: 337-338