Hydrosaurus pustulatus (Eschscholtz, 1829)

Common Names and Endemic Status

Hydrosaurus pustulatus, commonly known as the Philippine sailfin lizard or Philippine sailfin dragon, is a large semiaquatic agamid lizard endemic to all major island groups of the Philippines except the Palawan islands.

Dorsal Crest Feature

Like other sailfin lizards, this species has characteristic large, sail-like dorsal crests on its tail.

Maximum Size

It can reach a maximum total length of 3 to 4 feet (0.91 to 1.22 meters).

Swimming and Water Running Ability

It is a strong swimmer, and smaller juveniles are able to run briefly across the surface of water.

General Habitat

This lizard lives in areas with heavy vegetation near coastlines and low-lying rivers, especially in mangrove forests.

Local Common Names

Local common names for this species include layagan and balubid in Tagalog, and ibid in Visayan languages, among other local names.

National Protection Status

H. pustulatus is a protected species in the Philippines.

Exotic Pet Trade Threat

It is targeted by the international exotic pet trade because of its unique dorsal crests and bright coloration.

Deforestation Threat

Extensive mangrove deforestation over recent decades also poses a threat to its conservation.

Overall Distribution Range

The Philippine sailfin lizard occurs across the Philippine islands, excluding the Palawan islands.

Documented Population Locations

Documented populations exist in Luzon (Aurora, Bicol), Polillo Islands, Samar, Leyte, Dinagat Islands, Camiguin, Bohol, Negros, Panay, Romblon (Romblon Island, Tablas, Sibuyan), Mindoro, and Mindanao (Zamboanga).

Specific Inhabited Habitats

This species inhabits tropical wooded habitats located close to water, including rivers, riverbanks, rice fields, and mangrove forests.

Population Density and Habitat Preference

It occurs at moderately high population densities in these habitats, and it prefers to live near freshwater bodies of water.

Territorial Display Behavior

Philippine sailfin lizards use their sailfins and scales during territorial displays when encountering competing males or potential threats.

Breeding Frequency

They breed only once per year, but may produce multiple clutches of eggs in a single breeding season.

Egg Laying Behavior

After mating, females dig relatively shallow holes in soil near their aquatic habitats to lay their eggs.

Incubation and Hatching Period

Eggs incubate for approximately two months, and hatching occurs during the rainy season.

Clutch Details

Females can lay several clutches of eggs per year; each clutch holds between two and eight eggs, and clutches are laid above the flood line.