Photo Disclaimer
Description
Leachianus Gecko (Bayonnaise)
Scientific Name: Rhacodactylus leachianus
Common Name: Leachianus Gecko, New Caledonian Giant Gecko (Bayonnaise locality)
Species Overview
Size: Adult Bayonnaise Leachianus Geckos typically reach 12–14 inches (30–36 cm) in total length, including the tail, with some individuals exceeding this range. They are robust, muscular geckos—among the largest gecko species in the world.
Appearance: The Bayonnaise locality of Rhacodactylus leachianus is known for its striking pattern and earthy coloration, featuring tones of olive, grey, and brown mixed with pink, cream, or mossy green marbling. Their skin has a slightly velvety texture and camouflages beautifully against bark and moss. The head is broad with pronounced jowls, and the tail is thick and slightly flattened. Bayonnaise individuals are noted for their bolder contrasts and richer colour depth compared to some other localities.
Distribution: Endemic to Bayonnaise Island, part of the New Caledonian archipelago in the South Pacific.
Habitat: In the wild, these geckos inhabit humid forests and coastal woodlands, residing within tree hollows and bark crevices. In captivity, they thrive in large, vertically oriented enclosures that provide ample space for climbing and environmental stability.
Behaviour: Leachianus Geckos are nocturnal, territorial, and intelligent. They are well-known for their vocalisations—chirps, growls, and barks—used for communication and defense. While often curious and observant, adults can be defensive if startled, particularly during breeding. They are best appreciated as display reptiles rather than handled pets due to their size and strong personalities.
Captive Care
Enclosure: Provide a vertically oriented enclosure measuring at least 24 inches × 18 inches × 36 inches (60 × 45 × 90 cm) for a single adult. Include large cork rounds, sturdy branches, and dense foliage for climbing and security. Naturalistic setups with live plants are highly recommended to help maintain humidity and replicate their native habitat.
Temperature & Humidity: Maintain daytime temperatures between 75–82°F (24–28°C) and allow nighttime drops to 68–72°F (20–22°C). Avoid temperatures above 85°F (29°C). Humidity should remain between 60–80%, achieved with daily misting and adequate airflow. Allow brief drying periods between mistings to prevent mould and bacteria growth.
Lighting: Although nocturnal, Leachianus Geckos benefit from low-level UVB lighting (2–5%) to support calcium metabolism and natural circadian function. Use a 12-hour day/night cycle with shaded areas for retreat.
Diet: Feed a varied diet of high-quality commercial gecko diets (CGD) designed for Rhacodactylus species, supplemented occasionally with gut-loaded insects such as roaches or crickets. Adults may be fed 3–4 times weekly, while juveniles require smaller, more frequent feedings.
Behaviour in Captivity: Bayonnaise Leachianus Geckos are intelligent and often recognize routine feeding times. With consistent care and minimal disturbance, they thrive long-term and can live well over 20 years in captivity. Males and females can be territorial, especially during breeding season.
Special Considerations: Never house multiple adults together unless they are a proven, compatible pair. Monitor closely during introductions, as aggression can be severe. Avoid overheating, ensure proper humidity, and provide numerous hiding spots to minimize stress.
Taxonomy Note
The Leachianus Gecko (Rhacodactylus leachianus) belongs to the family Diplodactylidae and is native to New Caledonia. The Bayonnaise form represents a distinct island locality, exhibiting unique colouration and patterning compared to other populations such as Poindimié or Nuu Ana. These differences are the result of geographic isolation rather than formal subspecies distinctions.
Genetics Note
There are no recognised selective morphs of Rhacodactylus leachianus, but natural variation is pronounced among island localities. Breeders maintain pure locality lines (such as Bayonnaise, Poindimié, or Nuu Ana) to preserve the genetic identity and appearance of each population, rather than creating cross-locality hybrids.