Added 23 January 2013. Last updated 12 June 2022: removed Australian species.

A look at the Family Agamidae

Physignathus

Asian Water Dragons

Introduction

Asian water dragons are among the better known and more popular of the agamid lizards, and have been kept in captivity fairly regularly since the 1990s. At the same time they do have certain requirements which must be met if they are to thrive, mainly a reasonably large vivarium with access to a body of water. The Chinese Water Dragon, P. concinncus, in particular is renowned for bashing its snout raw against glass, often leading to serious injury or infection. This can only be avoided by an appropriate sized enclosure, and sometimes by marking the glass so that the lizard can see it is a barrier. They have been likened to smaller versions of the Green Iguana, but unlike the latter consume more insectivorous prey.

Boulenger listed the characteristics of the genus as follows: tympanum distinct; body more or less compressed; nuchal and dorsal crests present; no gular sac; strong transverse gular fold; tail round or more or less compressed; toes not lobate; femoral pores present, at least in the male. Both species are good swimmers.

Australian Water Dragons were once considered part of Physignathus but were moved into their own genus, Intellagama.

Husbandry details are available in deVosjoli, Manthey and Schuster and Rogner. See also the index of agamid-related articles under Physignathus and Intellagama, as both species have been covered several times over the past 10 years or so.

Species Name

Common Name

Distribution

Size

Notes

Physignathus 

P. cocincinnus 

Asian Water Dragon, Chinese Water Dragon 

E/SE Thailand, Cambodia, Vietnam, S China, poss. Burma

SVL to 25 cm, tail about 2½x SVL; max TL 90cm

In nature this species is normally found in evergreen forests or mixed evergreen/deciduous/bamboo forests [Stuart & Emmett] near water, often on branches overhanging streams. In captivity they are prone to snout injuries, so the cage must be a suitable size (deVosjoli suggests 6' for a pair) and arranged so that the lizards are less likely to run into the glass and injure themselves. Scalation details: canthus rostralis well marked; nostril nearer end of snout than orbit; rostral a little wider than high, bordered behind by 2 supralabials and 8 postrostrals; nasals rather small, surrounded by a ring of slightly elevated scales separated from rostral by 3 scales and from labials by 5 rows scales; about 10 rows separating nasals; 4-5 enlarged suboculars; 12 supralabials, 11 infralabials; dorsal head scales minute, granular, keeled, a little enlarged on canthus rostralis and supraorbital border (as per Taylor, slightly larger on snout than on rest of head); gular scales large juxtaposed granules, unequal on the sides, and 3-4 of posterior lateral ones largest and conical; series of 6-11 large shields on each side, parallel with infralabials. Dorsal scalation: scales equal, minute, granular, feebly keeled; nuchal crest composed of lanceolate spines supported by fold of skin covered in granular scales, spines being short in young males but very long in adult males; dorsal crest similar, slightly lower on shoulders but continous with nuchal crest. Ventral scalation: scales larger, imbricate, smooth.Tail: strongly compressed; crest as developed as, but not continous with, dorsal crest; lower caudal scales enlarged and strongly keeled. Other: head moderately elongate; snout slightly longer than diameter of orbit; tympanum one third diameter of orbit; 11-18 molar teeth on each side of upper jaw and 12-18 on each side of lower jaw; limbs long, covered with minute, slightly imbricate, keeled scales; 3rd and 4th toes subequal with 22 lamellae on underside, each with 2 keels; 4th toe very much larger, with 2-3 rows of irregular scales underneath and about 34 scales in each row; 4-5 (sometimes up to 8?) pores under basal part of each thigh. Coloration: overall green, a little lighter ventrolaterally; indistinct narrow transverse bands of a lighter colour on the sides; enlarged gular shields and tubercles whitish; tail with dark-brown annuli. Reproduction: males have swollen cheeks; females can be distinguished by lack of crests; clutch of 8-12 eggs laid in exposed sandy patch in stream bed; hatching takes 9-10 weeks. [SOURCES: Boulenger, Cox et al, Taylor]

Bibliography

Links

Tricia's Chinese Water Dragon page has been going for over a decade now.

See also the index of agamid-related articles, which has several listed for the two species.