Boyd's forest dragon (''Lophosaurus boydii'') is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

arboreal Arboreal locomotion is the Animal locomotion, locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally, but others are exclusively arboreal. Th ...

lizard Lizards are a widespread group of squamate reptiles, with over 7,000 species, ranging across all continents except Antarctica, as well as most oceanic island chains. The group is paraphyletic since it excludes the snakes and Amphisbaenia alt ...

in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Agamidae Agamidae is a family (biology), family of over 300 species of iguanian lizards indigenous to Africa, Asia, Australia, and a few in Southern Europe. Many species are commonly called dragons or dragon lizards. Overview phylogenetics, Phylogenetic ...

. The species is native to

rainforest Rainforests are characterized by a closed and continuous tree canopy, moisture-dependent vegetation, the presence of epiphytes and lianas and the absence of wildfire. Rainforest can be classified as tropical rainforest or temperate rainfores ...

s and their margins in the Wet Tropics region of northern

Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , established_ ...

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

. It is the larger of the two species of ''Lophosaurus'' found in Australia. Another species, the southern angle-headed dragon, ''L. spinipes'', is found in southern Queensland and northern

New South Wales ) , nickname = , image_map = New South Wales in Australia.svg , map_caption = Location of New South Wales in AustraliaCoordinates: , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , es ...

Etymology

The

generic Generic or generics may refer to: In business * Generic term, a common name used for a range or class of similar things not protected by trademark * Generic brand, a brand for a product that does not have an associated brand or trademark, other ...

name ''Lophosaurus'' stands for "crested lizard", from the Greek ''lophos'' for "crest", and ''saurus'' for "lizard". The specific name, ''boydii'', is a reference to

English English usually refers to: * English language * English people English may also refer to: Peoples, culture, and language * ''English'', an adjective for something of, from, or related to England ** English national ide ...

-born John Archibald Boyd (1846–1926), who lived in

Fiji Fiji ( , ,; fj, Viti, ; Fiji Hindi: फ़िजी, ''Fijī''), officially the Republic of Fiji, is an island country in Melanesia, part of Oceania in the South Pacific Ocean. It lies about north-northeast of New Zealand. Fiji consists ...

from 1865 to 1882 and then on a sugar plantation at

Ingham, Queensland Ingham is a rural town and locality in the Shire of Hinchinbrook, Queensland, Australia. In the , the locality of Ingham had a population of 4,426 people. It is named after William Bairstow Ingham and is the administrative centre for the Shire o ...

, and collected specimens for the

Australian Museum The Australian Museum is a heritage-listed museum at 1 William Street, Sydney central business district, New South Wales, Australia. It is the oldest museum in Australia,Design 5, 2016, p.1 and the fifth oldest natural history museum in the ...

. The

binomial authority In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

William John Macleay Sir William John Macleay (13 June 1820 – 7 December 1891) was a Scottish-Australian politician, Natural history, naturalist, zoologist, and Herpetology, herpetologist. Early life Macleay was born at Wick, Highland, Wick, Caithness, Scotland, ...

, who provided the original description of the species in 1884.

Geographic range and habitat

The species ''L. boydii'' is restricted to rainforests and their margins in northern

, from just north of

Townsville Townsville is a city on the north-eastern coast of Queensland, Australia. With a population of 180,820 as of June 2018, it is the largest settlement in North Queensland; it is unofficially considered its capital. Estimated resident population, 3 ...

to near

Cooktown Cooktown is a coastal town and locality in the Shire of Cook, Queensland, Australia. Cooktown is at the mouth of the Endeavour River, on Cape York Peninsula in Far North Queensland where James Cook beached his ship, the Endeavour, for repairs ...

. It is found in both upland and lowland rainforest, and is often seen around Lake Eacham (Yidyam) and

Lake Barrine Lake Barrine is a freshwater lake on the eastern parts of Atherton Tableland in the locality of Lake Barrine, in the Tablelands Region of Far North Queensland, Australia, close to Lake Eacham. The lake and surrounds are protected within th ...

, and in parts of

Malanda Falls Conservation Park Malanda Falls Conservation Park is located on the Malanda–Atherton Road, 1 km from Malanda, Queensland, on the Atherton Tableland, Australia. The Park protects a small tropical rainforest remnant. The Malanda Falls, on the North Johnstone Ri ...

and at

Mossman Gorge Mossman Gorge is a rural locality in the Shire of Douglas, Queensland, Australia. In the , Mossman Gorge had a population of 246 people. The locality takes its name from the valley Mossman Gorge created by the Mossman River through the Daintree ...

. It is recorded using tree-hollows.

Description

Boyd's forest dragon is generally brown or grey above, with some individuals having a green flush. The body is laterally compressed. It has very enlarged cheek scales, a prominent

nuchal The nape is the back of the neck. In technical anatomical/medical terminology, the nape is also called the nucha (from the Medieval Latin rendering of the Arabic , "spinal marrow"). The corresponding adjective is ''nuchal'', as in the term ''nu ...

crest, and a yellow

dewlap A dewlap is a longitudinal flap of skin or similar flesh that hangs beneath the lower jaw or neck of many vertebrates. More loosely, it can be various similar structures in the neck area, such as those caused by a double chin or the submandibula ...

under the chin that is edged with enlarged spines. The tympanum is large and superficial. A

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage * Dorsal co ...

crest, discontinuous with the nuchal crest, consisting of enlarged, hardened and pointed scales, runs down to the base of the tail. Adults are

sexually dimorphic Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...

, with males larger than females and having larger, blockier heads. Adult males grow to an average body length (snout-vent length) of about , with the tail adding another ; average body length for adult females is about and tail length is about . Average body mass for adult males is about , and for females is about .

Behavior

Boyd's forest dragon spends the majority of its time perched on the trunks of trees, usually at around head height, although daily movements can exceed on the ground. When approached, it will usually move around to the opposite side of the tree, keeping the trunk between it and its harasser. Unlike most other lizards, Boyd's forest dragon does not bask in the sun, instead letting its body temperature fluctuate with air temperature ( thermoconforming rather than thermoregulating). The one possible exception to this general rule is gravid (pregnant) females, which are often observed sitting on or beside forest roads and exhibit elevated body temperatures. Boyd's forest dragon typically commences activity at dawn and ceases activity at dusk, remaining active even when it rains. Activity is highly seasonal, all but ceasing during the cooler months, when lizards typically move into the rainforest canopy. Both males and females appear to be territorial, with males defending an area of around 1,000 square metres (0.247 acre). Female territories are smaller, with male territories often containing the territories of more than one female. Hatchlings, juveniles and smaller adults can often be found "sleeping" at night at the ends of tree branches with the head pointing back towards the trunk.

Diet

Boyd's forest dragon is a sit-and-wait predator, catching

prey Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill the ...

that it spies from its perch, although once on the ground, it will frequently move over a wider area, catching prey as it goes. Its diet consists primarily of

invertebrate Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...

s, with

earthworm An earthworm is a terrestrial invertebrate that belongs to the phylum Annelida. They exhibit a tube-within-a-tube body plan; they are externally segmented with corresponding internal segmentation; and they usually have setae on all segments. Th ...

s making up a relatively high proportion. Small

fruit In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particu ...

s and

vertebrate Vertebrates () comprise all animal taxa within the subphylum Vertebrata () ( chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, ...

s are also occasionally consumed.

Reproduction

Reproduction in ''L. boydii'' is via

eggs Humans and human ancestors have scavenged and eaten animal eggs for millions of years. Humans in Southeast Asia had domesticated chickens and harvested their eggs for food by 1,500 BCE. The most widely consumed eggs are those of fowl, especial ...

, with

clutch A clutch is a mechanical device that engages and disengages power transmission, especially from a drive shaft to a driven shaft. In the simplest application, clutches connect and disconnect two rotating shafts (drive shafts or line shafts). ...

sizes varying from one to six eggs. Eggs are about long and wide, and weigh about . Egg size and weight are both higher in upland populations. Females in lowland populations may lay more than one clutch in a season, but clutch sizes are typically smaller than those laid by upland females. The eggs are laid in shallow nests, often in rainforest clearings — both natural and man-made (the verges of roads are particularly popular). The eggs take about 100 days to incubate. Sexual maturity is achieved in around one to two years in lowland populations but probably takes at least a year longer in upland populations.

Predators

Known predators of juvenile and adult Boyd's forest dragon include

grey goshawk The grey goshawk (''Accipiter novaehollandiae'') is a strongly built, medium-sized bird of prey in the family ''Accipitridae'' that is found in eastern and northern Australia. The white morph of this species is known as the white goshawk. Tax ...

s and

feral pig The feral pig is a domestic pig which has gone feral, meaning it lives in the wild. They are found mostly in the Americas and Australia. Razorback and wild hog are Americanisms applied to feral pigs or boar-pig hybrids. Definition A feral pi ...

s. Slaty-grey snakes (''Stegonotus cucullatus'') have also been known to eat forest dragon eggs.

Parasites

Small orange mites are commonly found on the dewlap and in the groin areas of the legs of Boyd's forest dragon.

References

External links

Boyd's Forest DragonTropical Topics
{{Taxonbar, from=Q2711409 Lophosaurus Agamid lizards of Australia Reptiles of Queensland Endemic fauna of Australia Reptiles described in 1884 Taxa named by William John Macleay