Emerald Tree Monitor

Appearance

The emerald tree monitor is about 75–100 centimetres long with a slender body that helps it support itself on narrow branches. It also has a prehensile tail and long claws that it uses to grip branches. Unlike other varanids this monitor defends its tail rather than lashing with it for defense when threatened. The soles of the feet of the emerald tree monitor have enlarged scales which aid the lizard when climbing.

Distribution

Emerald tree monitors and their close relatives can be found in New Guinea, as well as several adjacent islands, and the northern Torres Strait Islands. The green tree monitor is reported to thrive in lowland environments including tropical evergreen forests, palm swamps and cocoa plantations.

Habitat

When threatened, the emerald tree monitor will flee through vegetation or bite if cornered. It is one of the few social monitors, living in small groups made up of a dominant male, several females, and a few other males and juveniles.

Reproduction

Clutches consist of up to five eggs, each weighing 10.5–11.5 grams and measuring about 2 by 4.5 centimetres. As many as three clutches are laid throughout the year; captive clutches have been laid in January, March, April, November, and December. The female emerald tree monitor lays her eggs in arboreal termite nests. The eggs hatch between 160–190 days, typically from June to November after which the young eat the termites and the termite's eggs within minutes of hatching. Sexual maturity is reached in about two years.

Food

The emerald tree monitor's diet consists of large tree dwelling insects such as katydids, stick insects, cockroaches, beetles, centipedes, spiders, crabs, birds, and small mammals. Before swallowing stick insects, the lizards tear off the legs. Captive specimens tear off the limbs of rodents prior to eating them and as a result they are capable of swallowing mammals of a considerable size: A 135-gram lizard was documented as eating a 40-gram rodent, an animal almost one-third its size. Paleontologist and Biology Professor at Temple University, Michael Balsai has observed "V. prasinus" eating fruit in captivity as has herpetologist and author, Robert G. Sprackland.

Evolution

The evolutionary development of "V. prasinus" started with the "Varanus" genus, which originated in Asia about 40 million years ago and migrated to Australia and the Indonesian archipelago around 15 million years ago.