Physignathus cocincinus

🔤 Taxonomy

Physignathus cocincinus is the accepted scientific name for the Chinese water dragon covered here. Use this Latin name when comparing labels, origin documents, and close relatives, because trade names can overlap.

English common names used in the hobby:

• Chinese water dragon

German common names used in the hobby:

• Grüner Wasseragame

📌 Description

Physignathus cocincinus is a non-venomous lizard with care needs shaped by its natural habitat: humid broadleaf forest beside streams, pools, and rivers, with branches over water. Adults are usually around 60-90 cm total length, and a realistic captive lifespan is 10-15 years when housing, diet, and veterinary care are handled well.

This is not an impulse animal. The enclosure has to be planned around adult size, daily maintenance, heat and humidity measurement, and the keeper’s ability to notice stress before it turns into disease. Captive-bred animals from transparent sources are strongly preferable, especially for species that have a history of wild collection.

The most useful care mindset is to build choices into the enclosure. The animal should be able to warm up, cool down, hide, drink, feed, and move without being forced into constant exposure.

🌍 Distribution

Physignathus cocincinus is native to tropical forests and stream margins in southern China and mainland Southeast Asia. In nature it is associated with humid broadleaf forest beside streams, pools, and rivers, with branches over water. That distribution should be read as a care clue rather than copied as one fixed number: the animal uses shade, cover, burrows, vegetation, water, season, and daily movement to choose suitable microclimates.

For captive care, the useful lessons are:

• secure retreats and visual cover
• a measured thermal gradient instead of one uniform temperature
• humidity that matches the species without stagnant wet air
• clean water and predictable hygiene
• enough usable space for normal movement

⚖️ Legal status

As checked against current CITES Appendices and Species+ references in May 2026, Physignathus cocincinus is listed in CITES Appendix II and is normally treated under EU wildlife-trade rules as Annex B unless a stricter national rule applies. It is not relevant to the Bern Convention because it is not native to Europe. Keep invoices, breeder records, import/export paperwork where relevant, and proof of legal origin. National rules on ownership, registration, sale, breeding, transport, and dangerous-animal lists may still apply.

🤌 Husbandry

Plan for at least 180 x 90 x 180 cm for one adult, with a large clean swimming basin. Smaller juvenile setups can be useful for monitoring feeding and shedding, but they must still include a warm area, a cool area, water, cover, and secure ventilation. Bare oversized enclosures often make new animals defensive or inactive; clutter and sight breaks make space usable.

House this species singly unless a breeding plan, enclosure size, and animal compatibility are already proven. Daily checks should include water quality, waste, locks, temperature, humidity, appetite, skin or shed condition, rostral rubbing, and behaviour.

Use digital thermometers and hygrometers rather than guessing. Record feeding, weight, sheds, cleaning, and veterinary issues. A simple log makes seasonal changes, gradual weight gain, and early illness much easier to interpret.

💡 Lighting

Provide a clear day-night rhythm with bright visible light and appropriate UVB. No visible night lights should shine into the enclosure; use darkness at night unless short observation is necessary.

For UVB-using reptiles, use a linear T5 lamp matched to the species, distance, mesh, and reflector. Provide shade and plant cover so the animal can leave the UV zone. Replace lamps on schedule and measure UVI when possible; powder supplements are not a replacement for correct light, heat, and diet.

🌡 Heating and temperature

Practical temperature targets: basking 32-35 °C, warm upper zone 27-30 °C, lower cool zone 24-26 °C, night 23-25 °C. These values should create a gradient, not a single average. Measure basking surfaces with an infrared thermometer and ambient zones with digital probes.

Every heat source must be controlled by a thermostat or dimming controller where appropriate. Avoid heat rocks and unguarded bulbs. If the animal avoids the warm zone, gapes constantly, soaks all the time, refuses food, or stays hidden for days, verify the actual temperatures before changing diet or handling.

💧 Humidity and water

Target humidity and water management: 60-80% by day with higher night humidity and strong ventilation. Humidity should be paired with ventilation. Constantly wet, dirty air is not the same as healthy humidity, and chronic dryness is a common cause of dehydration and bad sheds.

Fresh water should always be available in the form this species uses: a large clean basin for drinking, soaking, and swimming, plus misting or rain-style droplets that support hydration without turning the air stagnant.

🌿 Enclosure and decoration

The enclosure should be functional first and attractive second. Use secure hides, branches, cork, live or artificial plants, rough shedding surfaces, safe digging or climbing zones, and enough visual barriers that the animal can move without feeling exposed. Heavy-bodied species need furnishings that cannot collapse.

Substrate should support the humidity and behaviour of the species while staying clean. Avoid dusty bedding, sharp decor, sticky tape inside the enclosure, unstable rocks, and small loose items that could be swallowed. Doors, vents, cable ports, and lids must be escape-proof.

🪳 Feeding

Feed a varied, species-appropriate diet: gut-loaded insects as the staple, plus earthworms, roaches, locusts, occasional snails, small fish or pinkies as rare treats, and some leafy plants. Young animals usually need smaller and more frequent meals; adults need body-condition-based feeding rather than food every time they appear interested. Overfeeding is as real a welfare problem as underfeeding.

Feeder insects should be gut-loaded and dusted according to the UVB plan. Remove uneaten food before it spoils, avoid oversized prey, and do not leave live feeders where they can injure the lizard.

🩺 Common problems

Common problems include rostral rubbing, mouth injuries, dirty water, respiratory infections, dehydration, burns, and obesity. Warning signs include weight loss, repeated refusal to eat, weak grip or poor movement, wheezing, bubbles at the nostrils, swollen eyes, repeated bad sheds, mouth injury, burns, diarrhoea, or unusual aggression from an otherwise settled animal.

When something looks wrong, first verify the basics with instruments: warm zone, cool zone, night temperature, humidity, hydration, hide fit, diet, and recent stress. Serious weakness, injury, breathing signs, repeated regurgitation, neurological signs, or rapid decline need an experienced exotic-animal veterinarian.

📌 Conclusion

Physignathus cocincinus can be kept responsibly when the keeper plans for the adult animal and treats legal origin, measured climate, suitable diet, and veterinary access as part of the setup. The best enclosure is not the most decorative one; it is the one that gives the animal safe choices every day.

📚 Sources and further reading

• CITES Appendices, checked 2026-05-04
• GBIF species backbone entry for Physignathus cocincinus
• Species+ CITES and EU wildlife-trade references, checked May 2026
• EU invasive alien species policy pages, checked May 2026 where relevant
• ReptiFiles and specialist husbandry references where available