Hydrosaurus

This article is about a lizard genus. For the mosasaur genus which previously held the same name, see Pontosaurus.

Hydrosaurus, commonly known as the sailfin dragons or sailfin lizards, is a genus in the family Agamidae.^[2] These relatively large lizards are named after the sail-like structure on their tails. They are native to Indonesia (four species) and the Philippines (one species), where they are generally found near water, such as rivers and mangrove swamps.^[3] Sailfin lizards are semiaquatic and able to run short distances across water using both their feet and tail for support, similar to the basilisks.^[4] They are threatened by both habitat loss and overcollection for the wild-animal trade.^[3]

Hydrosaurus
Hydrosaurus amboinensis
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	Squamata
Suborder:	Iguania
Family:	Agamidae
Subfamily:	Hydrosaurinae Kaup, 1828
Genus:	Hydrosaurus Kaup, 1828[1]
Type species
Hydrosaurus amboinensis
Species
Hydrosaurus amboinensis Hydrosaurus celebensis Hydrosaurus microlophus Hydrosaurus pustulatus Hydrosaurus weberi
Synonyms
Lophura Gray, 1827 Istiurus Cuvier, 1829

In the 19th century, the genus was called Lophura, but in 1903, Poche pointed out that the name was preoccupied by a genus of pheasants.^[5] Since Günther in 1873, the Sulawesi populations were considered to belong to H. amboinensis; Denzer et al. in 2020 resurrected H. celebensis and H. microlophus, increasing the number of species from three to five.^[5]

They are the only members of the subfamily Hydrosaurinae.

Species

Currently, five species are valid according to the Reptile Database,^[2][3][5]

Image	Scientific name	Common name	Distribution
	Hydrosaurus amboinensis (Schlosser, 1768)	Moluccan sailfin lizard or Amboina sail-finned lizard, soa-soa water lizard	Western New Guinea, Ambon/Amboina Island and Ceram Island (Indonesia)
	Hydrosaurus celebensis (Peters, 1872)	Sulawesi black sailfin lizard	Indonesia (Sulawesi)
	Hydrosaurus microlophus (Bleeker, 1860)	Indonesian giant sailfin dragon, Makassar sailfin lizard, or Sulawesi giant sailfin dragon	Indonesia (Sulawesi)
	Hydrosaurus pustulatus (Eschsholtz, 1829)	Philippine sailfin lizard, layagan, balubid, or ibid[6][7]	Philippine archipelago (except Palawan)[8]
	Hydrosaurus weberi Barbour, 1911	Weber's sailfin lizard	Ternate Island, North Maluku (Indonesia) Halmahera Island, North Maluku (Indonesia)