Gonocephalus bornensis (Schlegel, 1851)

Species Nomenclature and Size Overview

Gonocephalus bornensis (Schlegel, 1851) is a moderately sized lizard, with a maximum snout-vent length (SVL) of 136 mm.

Sexual Size Dimorphism

Males are generally larger than females: male SVL ranges from 118 to 136 mm, while female SVL ranges from 90 to 130 mm; male tail length ranges from 261 to 310 mm, while female tail length ranges from 215 to 275 mm.

Head and Dorsum Morphology

This species has a circular border on the supercilium, a rather small tympanum, and a weakly granular dorsum.

Crest Structure

It also has a prominent lanceolate crest that begins on the neck and ends on the lower back.

Tail Morphology

Its tail is almost cylindrical.

Sub-adult Male Coloration

Sub-adult males typically have brown, olive, and green dorsal and lateral coloration, and often have dark reticulations across their skin.

Adult Male Coloration

Adult males are predominantly green, with faint, indistinct reticulation.

Iris Coloration

The iris may be deep brown or light blue.

Female Coloration

Females have rust red dorsolateral coloration, with oval spots formed by reticulations along the sides of their body.

Endemic Range

This species is endemic to Borneo.

Specific Distribution Locations

It is common in Mount Kinabalu and Poring Hot Spring in Sabah, and can also be found in Brunei, Sarawak, and Kalimantan.

Habitat and Elevation Range

Gonocephalus bornensis inhabits primary and secondary rainforests, at elevations up to 700 m above sea level.

Microhabitat Preference

It is arboreal, and typically lives on tree trunks and lianas, most often near streams.

Egg Laying Behavior

Females deposit eggs in small burrows dug into soil.

Clutch Characteristics

Each clutch contains up to four eggs, each measuring 22 mm in length, and clutches are laid at three-month intervals.