Vietnamese Mossy Frog

🔤 Taxonomy

Theloderma corticale is the accepted scientific name for the Vietnamese mossy frog, a cool-humidity arboreal frog from northern Vietnam and nearby regions.

Common names used in care literature and trade:

• Vietnamese mossy frog
• Mossy frog
• Tonkin bug-eyed frog

📌 Description

Vietnamese mossy frogs are cryptic, rough-skinned frogs whose green, black and brown pattern helps them disappear against wet moss, bark and rock. They are mostly nocturnal and often rest above or near cool clean water.

This is an intermediate display species. It tolerates neither heat nor dirty water well, so the keeper’s main job is to keep the enclosure cool, humid, ventilated and hygienic without making it stale.

📋 Quick reference

🌍 Distribution

Theloderma corticale is associated with cool humid forest, karst, tree holes, rock cavities and water-filled retreats in northern Vietnam and nearby areas. Its camouflage and behavior are tied to wet vertical surfaces, shaded cover and clean standing or slow-moving water.

Captive care should focus on cool air, shaded climbing structure, clean water, and airflow. A warm tropical frog tank is the wrong model.

⚖️ Legal status

This article records Theloderma corticale as not listed in the CITES Appendices, not listed in EU Wildlife Trade Annexes A-D, and not relevant to the Bern Convention because it is not native to Europe. The legal check was updated on 2026-06-11.

Not listed does not mean unregulated. Import, sale, transport, exhibition and welfare rules may still apply, and amphibian disease controls can affect movement between facilities or countries. Keep invoices and captive-bred origin records.

🤌 Husbandry

Build the enclosure vertically, with cork, branches, broad leaves, rough but skin-safe resting surfaces, and water access. Frogs should be able to rest above water, descend easily, and choose between more humid and more ventilated areas.

Small groups can work, but each frog must feed and maintain weight. Watch for dominant individuals occupying the best rests or feeding stations. Provide multiple hides and visual barriers rather than one central feature.

Avoid mixed-species displays. They increase disease, stress, feeding competition and legal-record confusion.

💡 Lighting

Use a 10-12 hour photoperiod with plant-friendly visible light. This species rests in shade by day, so lighting should support the enclosure without forcing frogs into exposed bright spots.

Low-level UVB can be useful when installed as Ferguson Zone 1. Aim for around UVI 0.5-1.0 in the upper exposed structure and near-zero in shaded cork, leaves and water retreats. Measure where possible and always provide shade.

🌡 Heating and temperature

Cool stability is the core requirement. Maintain 20-24°C by day, with a night drop to 16-20°C. A brief warm area around 24-26°C is acceptable only if the rest of the enclosure remains cool and the frogs can avoid it.

Overheating is a bigger risk than mild coolness. Temperatures near 27-28°C, especially with stagnant air, can cause stress quickly. In warm rooms, plan ventilation, evaporative cooling, seasonal room control, or a cooler location before buying the frogs.

💧 Humidity and water

Keep humidity around 70-90%, but do not seal the enclosure so tightly that air becomes stale. Surfaces can be wet after misting, then dry back to humid. Persistent slime, sour smell, or film on water means the system is too dirty or too stagnant.

Water must be dechlorinated and kept clean. Use easy exits, gentle access points, and no pump intakes that can trap toes or small frogs. For larger water sections, use regular water changes and monitor basic water quality; for simple bowls, change water daily or when soiled.

🌿 Enclosure, water system and quarantine

A 45 x 45 x 60 cm enclosure is a practical minimum for a small group, but larger vertical setups are easier to stabilize. Provide cork tubes, cork flats, branches, plants, shaded shelves, and a clean water zone. Avoid sharp rock edges and abrasive decor that can damage belly and toe skin.

If using a bioactive setup, keep the water side serviceable. Bioactive soil does not make dirty water safe, and filters do not remove the need for water changes. Keep electrical equipment guarded and outside frog reach where possible.

Quarantine new mossy frogs for 60-90 days with separate tools. Track weight, skin, feces, and feeding response. Discuss fecal parasite testing and chytrid screening with an amphibian veterinarian, especially for imported or unknown-history animals. Do not share water, nets, cups, plants or misting equipment between amphibian enclosures during quarantine.

🪳 Feeding and supplements

Feed varied, gut-loaded insects every 2-3 days. Suitable foods include crickets, roaches, locusts where legal, moths from safe cultures, and occasional soft-bodied larvae in moderation. Use prey that fits the frog’s head width and remove uneaten insects that may chew resting frogs.

Supplement schedule:

• juveniles and growing frogs: calcium at most feedings and a multivitamin about weekly
• adults with UVB: calcium 1-2 times weekly and multivitamin every 2-4 weeks
• adults without UVB: include a D3-containing calcium product periodically, but do not overdose D3
• gut-load feeders for 24-48 hours with safe greens, grains or commercial gut-load before feeding

Poor supplementation can produce metabolic bone disease, weak grip, tremors, poor posture and reproductive problems.

🥚 Breeding notes

Breeding is difficult and should wait until a stable cool-water system is proven. Eggs are usually deposited above or near water, and larvae require clean, appropriate water conditions. Do not attempt breeding without plans for tadpole water quality, small-food production, unrelated adults and placement of offspring.

Record parentage and dates. Even non-CITES species benefit from clear captive-bred records.

🧍 Handling and safety

Handle only when necessary. Use wet powder-free gloves, clean wet hands, or a damp container. Amphibian skin is easily damaged by dry handling, soap, lotion, disinfectant residue, nicotine residue and rough nets.

Secure doors and service openings before misting or feeding. Mossy frogs can wedge into cork tubes and plant bases, so count animals visually before moving decor.

🩺 Common problems

• Overheating: panting, frantic movement, soaking constantly, lethargy or collapse in warm stagnant enclosures.
• Water-quality dermatitis: redness, cloudy skin, sores or excessive shedding from dirty or chemically unsafe water.
• Chytridiomycosis and parasites: quarantine and test high-risk animals, especially imports.
• Metabolic bone disease: weak grip, tremors, poor posture, swelling or deformity from poor calcium, D3, UVB or feeder nutrition.
• Skin trauma: rough decor, narrow pump intakes, dry handling or feeder bites can cause wounds.
• Dysecdysis: retained skin or repeated poor shedding, often tied to humidity, water quality, nutrition or infection.

Loss of appetite, weight loss, swelling, abnormal buoyancy, persistent soaking, skin ulcers, respiratory signs or repeated falls need prompt husbandry review and veterinary help.

✅ Conclusion

The Vietnamese mossy frog is best for keepers who can keep a cool, clean, humid and well-ventilated water-and-branch system stable. Avoid heat, dirty water and excessive handling, and the species becomes a striking long-term display animal.

📚 Selected sources

• CITES Appendices, checked 2026-06-11
• European Commission Wildlife Trade Regulations, checked 2026-06-11
• Amphibian Species of the World: Theloderma corticale
• GBIF Backbone Taxonomy: Theloderma corticale
• UV Tool and Ferguson zone guidance