Gonyosoma jansenii

Vertical arboreal terrarium, planted / bioactive

A strictly arboreal species: prioritise height. These dimensions are a MINIMUM for an adult; a larger volume (150 x 80 x 180 cm or more) is strongly recommended. Provide sturdy horizontal and diagonal branches, dense foliage (real or artificial plants) to offer elevated hiding spots for this nervous species, and a very solid, locked lid (a powerful and restless snake).

A humid tropical-forest atmosphere. Maintain 60-70% daily with peaks of 80-90% during sheds, through misting and a moisture-retaining substrate. Good ventilation is imperative to prevent stagnation and respiratory infections.

A substrate that retains moisture without becoming waterlogged; a drainage layer and good aeration prevent waterlogging and the development of mould.

A diurnal species: low-intensity UVB is recommended (Ferguson zone 1-2, ~5-6% tube / UVI 1-2) for well-being and metabolism, though not strictly essential if the diet is complete and varied. Provide shaded areas and avoid close direct exposure.

Provide a large bowl of clean water, stable and refreshed regularly (it also allows bathing and hydration). This arboreal species readily drinks the droplets deposited on branches and foliage after misting: mist daily.

Endemic to the island of Sulawesi (Celebes) and neighbouring islands (Indonesia), in lowland and mid-mountain tropical rainforests.

Strict carnivore — In the wild: birds, bats and arboreal rodents (a visual hunter). In captivity: chicks, quail and appropriately sized rodents.

An active visual predator. Imported wild-caught specimens often prefer avian prey and may refuse rodents: scenting with a feather/chick helps the transition. Feed an adult every 7 to 14 days; monitor weight, as obesity is a risk in captivity. Thawed prey preferred.

Clutch 5–12 eggs/young. Breeding triggered by a mild seasonal cycling (a drop in temperature/photoperiod and a variation in humidity). Incubation of about 60 to 80 days around 27-28 °C in a moist substrate. Captive breeding is still poorly documented for this species.

• Respiratory infections (linked to unsuitable humidity/ventilation or temperature)
• Internal and external parasites, common in imported wild-caught specimens (nematodes, protozoa, cryptosporidiosis): quarantine and a faecal exam are essential
• Dehydration and difficult sheds (dysecdysis)
• Chronic stress and food refusal, especially in wild-caught individuals
• Thermal burns (unprotected heat sources) and stomatitis (mouth rot)