Vertebrate fauna of SE Asia


SE Asia fauna ...  
 Large Mammals
 Small Mammals
 Mammal calls
 Lizards & Crocodilians
 Frog calls
Freshwater Fishes
 Marine & Brackish Fishes
Species Lists


New Guinea herptiles ...  
Snakes   Lizards   Frogs  
SE Asia Vert Records (SEAVR) archives ...  
  Indochina Records
  Indonesia & PNG Records
Philippines Vertebrate Records (PVR)  
Philippines Records  
Email :
  New or updated pages ...

Search this site ...




Email :

Text and photos by Nick Baker, unless credited to others.
Copyright ゥ Ecology Asia 2024







Rasmussen's Water Monitor

Species : Varanus rasmusseni
Size (snout to vent) :  up to at least 46 cm
Size (total length) : up to at least 74 cm

Rasmussen's Water Monitor is known only from the southern Philippines, specifically the islands of Tawi-Tawi, Jolo and Bitinan in the Sulu Archipelago. Tawi-Tawi lies just 60 km off the northeastern coast of Borneo.

This monitor lizard was first described as a clearly distinct species by Koch et al in 2010. It is part of the Varanus salvator species group, and is thus closely related to the Malayan Water Monitor. In common with the latter, its nostrils   are located towards the front of the snout. It measures up to at least 1.2 metres total length.

Adults of this impressive monitor are mainly brown in colour (on ventral as well as dorsal surfaces): this is mottled with scattered, bright scales, and indistinct narrow pale bars on the tail.

Juveniles bear three indistinct dark bars on the snout, and a pale streak in the temporal region (the side of the head). The dorsal surfaces of the body, legs and tail of juveniles bear pale spots, and the distal half of the tail is banded.

Little is known about the ecology of this little-studied species.

Figs 1 to 3 : Example from Tawi-Tawi Island, Philippines.  Photos thanks to Ng Bee Choo.

References :

Koch, A., Gaulke, M., & Bhme, W. (2010). Unravelling the underestimated diversity of Philippine water monitor lizards (Squamata: Varanus salvator complex), with the description of two new species and a new subspecies. Zootaxa, 2446, 1-54.

Sy, Emerson Y. and Romulo Quemado. 2014. Geographic Distribution: Varanus rasmusseni (Rasmussen's water monitor lizard). Herpetological Review 45 (3): 464

Fig 1
ゥ  Ng Bee Choo
Fig 2
ゥ  Ng Bee Choo
Fig 3
ゥ  Ng Bee Choo