Philippine Sailfin Lizard  (Crested Lizard, Sail-fin Lizard, Sailfin Water Lizard, Soa-soa Water Lizard)

Hydrosaurus pustulatus (Agamidae) is a species of lizard notable not only for its impressive size of up to a meter in length, but also for its rather spectacular appearance.

Adults of this large mottled greenish-grey lizard boast a well-developed crest of tooth-like scales from the nape of the neck down the back. However, the most distinctive feature of adult males is the erect ‘sail’ of skin at the base of their tail, up to 8 cm high, which provides propulsion for this strong swimmer to move through the water, and probably also plays an important role in territorial display and thermoregulation.

This species, regarded as Vulnerable on the IUCN Red List, is endemic to the Philippines.

Reference: [1] - [2]

Photo credit: [Top: ©Shekainah D. Alaban | Locality: Masbate, Philippines] - [Middle: ©Shekainah D. Alaban | Locality: Masbate, Philippines]  -  [Bottom: ©Michael H. | Locality: Captive, Melbourne Zoo, Australia]