January 16, 2018
- as seen by -Don Boyer
The largest of the agamid lizards are the sailfin lizards in genus Hydrosaurus growing to a little over three feet in length. There are three species of these spectacular lizards living in parts of Indonesia, Papua New Guinea, and the Philippines.
Their Latin name literally means “water lizard,” an apt name for these tropical Asian lizards as they rarely stray far from water. Their preferred habitat is the water’s edge along rivers and streams where they can often be seen perched on branches or vegetation overhanging the water. At the first sign of danger they will plunge into the safety of the water and are excellent swimmers.
Their common name comes from the vertical fin-like crest on the neck and tail. This is much more pronounced in the males. They can even run across the surface of the water for a short distance. Their toes have extra fringe-like scales on the back edge that helps increase their foot size and giving them more propulsive power.
In all of the species, the male sailfins are more colorfully marked and quite territorial. They display to rivals, or conspecifics, by moving one of their front legs in a circular motion as if waving. They also using head bobbing to display social signals, and if none of that body language is sufficient, then quick pursuit and a nip at a rival does the trick. These lizards are omnivores feeding on a variety of leaves, fruits, flowers, insects and small vertebrate prey.
At the Wildlife Conservation Society’s Bronx Zoo, you can see two of the three species, Weber’s sailfin lizard and the Philippine sailfin lizard (above), on exhibit in the World of Reptiles or Jungle World.