Family : PAREIDAE
Species : Asthenodipsas vertebralis
Maximum Size : 77 cm

The Mountain Slug Snake has been found only in hill dipterocarp, submontane and montane primary forests of Peninsular Malaysia at elevations of around 1000-2000 metres. It is absent from the lowlands.

This is a nocturnal species, and is predominantly terrestrial, though it may climb a few metres from the ground in search of protection or prey. Slug snakes feed on snails and slugs, but little more is known of the detailed ecology of this highly localised species.

A typical example of this species comprises a dark grey to dark brown dorsum and a cream  underside. Numerous faint grey or brown bands occur in the central, thickest part of the body which is laterally compressed. In juveniles the dorsum is pale brown, and the banding is more apparent.

The head is blunt, the snout rounded, and the eyes large with a reddish-brown iris.

The specimen shown here was found by a roadside at Fraser's Hill, Pahang, Peninsular Malaysia at an approximate elevation of 1000 metres.

The species occurs in the main mountain range of Peninsular Malaysia, which runs like a spine throughout the length of much of the country, and also on Pulau Tioman, off the east coast of Pahang state.

A recently described and related species, the Mirkwood Forest Slug Snake Asthenodipsas lasgalenensis (Loredo et al, 2013), also occurs in highland areas of Peninsular Malaysia, but lacks banding and is mainly arboreal.

Fig 1 : Close-up of the head showing the rounded, blunt snout and large eyes.

Fig 2 : In defensive posture amongst dry leaf litter.

Figs 3 and 4 : Note the laterally compressed body and faint, pale vertebral line.

All images from Fraser's Hill, Peninsular Malaysia, thanks to Vilma D'Rozario.


References : H12, H14

Ariel I. Loredo, Perry L. Wood, Jr., Evan S. H. Quah, Shahrul Anuar, Lee F. Greer, Norhayati Ahmad & L. Lee Grismer  (2013). Cryptic speciation within Asthenodipsas vertebralis (Boulenger, 1900) (Squamata: Pareatidae), the description of a new species from Peninsular Malaysia, and the resurrection of A. tropidonotus (Lidth de Jude, 1923) from Sumatra: an integrative taxonomic analysis. Zootaxa 3664 (4): 505-524.