Panay monitor lizard (Varanus mabitang)

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Panay monitor lizard fact file

• Description
• Biology
• Range
• Habitat
• Status
• Threats
• Conservation
• Find out more
• Glossary
• References
• Print factsheet

Panay monitor lizard description

First described as recently as 2001, the Panay monitor lizard (Varanus mabitang) is a large, secretive monitor lizard (Varanus spp.) found only on the island of Panay in the Philippines ^{(2) (3)}. It has a relatively slender body and a long, thin head, with a pointed and slightly domed snout. The tail is slender and is triangular in cross section, and the scales on the tail are strongly keeled all the way to the tip ⁽³⁾.

The Panay monitor lizard is also characterised by its very large feet, which have long, slender toes and very long, curved, dark grey claws. The scales on its neck, body and tail are extremely small, and the eyes of this species are reddish-brown ⁽³⁾.

The Panay monitor lizard is almost uniformly black, with tiny yellow spots on some of the scales around the neck, back and extremities. Its underside is dark grey to blackish ^{(2) (3)}. This dark colouration is thought to help disguise the Panay monitor lizard within its naturally shady and densely vegetated habitat ⁽³⁾, and even juveniles are believed to be as uniformly dark as the adults ⁽²⁾.

This large lizard shares its general morphological traits and appearance with the closely related Gray’s monitor (Varanus olivaceus), including slit-like nostrils, blunt teeth, large feet, large head scales, and a large caecum, which is used to help digest its vegetarian diet ⁽³⁾. However, the Panay monitor lizard differs from its relative in being completely dark, rather than lighter greenish-grey with dark bands, and it lacks any patterning on the throat. It also has a more domed snout and more strongly keeled scales on the underparts, and its tail is triangular rather than oval in cross section ⁽³⁾.

Size

Total length: up to 175 cm ^{(2) (3)}

Snout-vent length: up to 70 cm ⁽²⁾

Tail length: up to 111 cm ⁽³⁾

Weight

1 - 8 kg ⁽²⁾

Panay monitor lizard biology

The Panay monitor lizard is a highly arboreal species ^{(1) (3)} and spends the majority of its day resting on branches in tree canopies or in cavities in the upper part of tree trunks ^{(2) (3)}. It is only rarely sighted on the ground, where it may feed on fallen fruits or bask in open areas. The Panay monitor lizard prefers to rest on tall trees with smooth trunks ⁽²⁾.

The diet of the Panay monitor lizard is unusual in being exclusively vegetarian. It feeds on the fruits of forest trees such as screw palms (Pandanus spp.) and fig trees (Ficus minahassae) ^{(2) (3)}, and it is also the only monitor lizard known to eat leaves ⁽³⁾. This entirely vegetarian diet appears to be unique among Varanus species, with the Panay monitor lizard’s close relative, Gray’s monitor (V. olivaceus), consuming snails in addition to fruit ⁽³⁾.

No specific information is available on the reproductive behaviour of the Panay monitor lizard. However, some dissected specimens have been reported to contain between 6 and 12 eggs ⁽⁶⁾.

Panay monitor lizard range

Panay Island in the Visayas Archipelago of the Philippines appears to be the only location where the rare Panay monitor lizard can be found ^{(1) (2) (3) (5)}. In addition to being endemic to this one island, the Panay monitor lizard is further limited to the rainforests in the island’s north-western and western mountain ranges ^{(1) (3)}.

This species has been recorded at elevations of around 200 to 1,000 metres, although it is believed to be rare above 600 metres ⁽¹⁾.

Panay monitor lizard habitat

The Panay monitor lizard is a highly specialised reptile that inhabits lowland tropical moist forest, where it relies on large trees for food and shelter ^{(1) (2) (3)}. It is unlikely to occur in habitats that have been modified by humans, particularly where food trees are absent ⁽¹⁾.

Some individuals of this species have occasionally been seen in more open areas along the forest edge, in secondary growth or along riverbanks. However, they are still dependent on the dense primary forest for food and places to sleep and breed. These sightings may also potentially represent misidentified individuals of the related Varanus nuchalis ⁽²⁾.

Panay monitor lizard status

The Panay monitor lizard is classified as Endangered (EN) on the IUCN Red List ⁽¹⁾ and is listed on Appendix II of CITES ⁽⁴⁾.

Panay monitor lizard threats

Habitat loss and fragmentation are the main threats to the Panay monitor lizard. Its lowland forest habitat is being lost to conversion for agricultural use and to logging operations ^{(1) (2)}, and is now the most endangered ecosystem on Panay ⁽²⁾.

Overhunting is also an issue, as the Panay monitor lizard is a favourite food in many of the local communities ⁽¹⁾. If the threats faced by this species and its habitat are not addressed very soon, the Panay monitor lizard is likely to experience a rapid extinction in the near future ⁽²⁾.

Panay monitor lizard conservation

On the island of Panay, non-governmental organisations are running ongoing projects to conserve the remaining suitable habitat for the Panay monitor lizard, and to study its biology and habitat requirements. These organisations include Patenschaften für Biologische Vielfalt e.V. (BIOPAT) and the Panay Eco-Social Conservation Project (PanayCon) ^{(1) (7) (8)}.

The Panay monitor lizard can be found in the Central Panay and North West Panay protected areas ⁽¹⁾, and is listed on Appendix II of the Convention on International Trade in Endangered Species (CITES), meaning that international trade in this large, rare reptile should be carefully controlled ⁽⁴⁾.

Find out more

Find out more about the Panay monitor lizard and other reptiles:

• The Reptile Database:
  http://reptile-database.reptarium.cz/search.php

More information about conservation on Panay:

• Patenschaften für Biologische Vielfalt e.V. (BIOPAT):
  http://www.biopat.de/englisch/index_e.htm
• Panay Eco-Social Conservation Project (PanayCon):
  http://www.panaycon.org/

Authentication

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
arkive@wildscreen.org.uk

This species information was authored as part of the ARKive and Universities Scheme.

Glossary

Arboreal

An animal which lives or spends a large amount of time in trees.

Caecum

A large pouch that receives waste material from the small intestine and marks the beginning of the large intestine. Most herbivores have a relatively large caecum, holding a large number of bacteria which assist with the breakdown of plant materials such as cellulose.

Endemic

A species or taxonomic group that is only found in one particular country or geographic area.

Keel

A projecting ridge along a flat or curved surface, particularly down the middle.

Morphological

Referring to the visible or measurable characteristics of an organism.

Primary forest

Forest that has remained undisturbed for a long time and has reached a mature condition.

Secondary growth

Vegetation that has re-grown after a major disturbance, such as fire or clearance.

References

1. IUCN Red List (February, 2012)
   http://www.iucnredlist.org/
2. Gaulke, M. (2010) Overview on the present knowledge on Varanus mabitang Gaulke and Curio, 2001, including new morphological and meristic data. Biawak, 4(2): 50-58.
3. Gaulke, M. and Curio, E. (2001) A new monitor lizard from Panay Island, Philippines (Reptilia, Sauria, Varanidae). Spixiana, 24(3): 275-286.
4. CITES (February, 2012)
   http://www.cites.org/
5. Böhme, W. (2003) Checklist of the living monitor lizards of the world (family Varanidae). Zoologische Verhandelingen, Leiden, 341: 3-43.
6. Pianka, E.R. and King, D.R. (Eds.) (2004) Varanoid Lizards of the World. Indiana University Press, Bloomington, Indiana.
7. Patenschaften für Biologische Vielfalt e.V. (BIOPAT) (July, 2012)
   http://www.biopat.de/englisch/index_e.htm
8. Panay Eco-Social Conservation Project (PanayCon) (July, 2012)
   http://www.panaycon.org/