Lophosaurus boydii (Macleay, 1884)

Dorsal Coloration

Boyd's forest dragon (Lophosaurus boydii) is generally brown or grey on its upper body, with some individuals having a greenish tint.

Body Shape

Its body is laterally compressed.

Head and Neck Scales

It has very enlarged cheek scales, a prominent nuchal crest, and a yellow dewlap under the chin edged with enlarged spines.

Tympanum Characteristics

The tympanum is large and superficial, lying close to the skin surface.

Dorsal Crest Structure

A dorsal crest that is discontinuous from the nuchal crest, made up of enlarged, hardened and pointed scales, runs down to the base of the tail.

Sexual Dimorphism

Adults are sexually dimorphic, with males larger than females and having larger, blockier heads.

Body Length

Adult males grow to an average snout-vent (body) length of about 160 mm (6.3 in), with the tail adding another 325 mm (12.8 in); the average snout-vent length for adult females is about 140 mm (5.5 in) and average tail length is about 280 mm (11 in).

Body Mass

The average body mass for adult males is about 150 g (5.3 oz), and for females it is about 100 g (3.5 oz).

Species Distribution Range

The species Lophosaurus boydii is restricted to rainforests and their margins in northern Queensland, Australia, ranging from just north of Townsville to near Cooktown.

Habitat Specifics

It occurs in both upland and lowland rainforest, and is often seen around Lake Eacham (Yidyam) and Lake Barrine, in parts of Malanda Falls Conservation Park, and at Mossman Gorge.

Shelter Use

It has been recorded using tree-hollows.

Reproduction Type and Clutch Size

Lophosaurus boydii reproduces via eggs, with clutch sizes varying from one to six eggs.

Egg Dimensions and Weight

Eggs are about 30 mm (1.2 in) long and 15 mm (0.59 in) wide, and weigh about 3–4.5 g (0.11–0.16 oz).

Upland Egg Traits

Both egg size and weight are higher in upland populations.

Lowland vs Upland Clutch Patterns

Females in lowland populations may lay more than one clutch in a season, but their clutch sizes are typically smaller than those laid by upland females.

Nesting Sites

Eggs are laid in shallow nests, often in rainforest clearings that are both natural and man-made—road verges are particularly popular nesting spots.

Incubation Period

The eggs take about 100 days to incubate.

Sexual Maturity Timeline

Sexual maturity is reached in around one to two years for lowland populations, but it probably takes at least a year longer for upland populations.