Australian water dragon

Last updated

Australian water dragon
Eastern Water Dragon Full.JPG
Intellagama lesueurii lesueurii
Gippsland Water Dragon (Intellegama lesueurii howitii) (8397094289).jpg
Intellagama lesueurii howittii
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Suborder: Iguania
Family: Agamidae
Genus: Intellagama
Wells & Wellington, 1985
Species:
I. lesueurii
Binomial name
Intellagama lesueurii
(Gray, 1831)
Subspecies
  • Intellagama lesueurii lesueurii
    (Gray, 1831)
    eastern water dragon
  • Intellagama lesuerii howittii
    (F. McCoy, 1884)
    Gippsland water dragon
Synonyms [2] [3]
  • Lophura lesueuriiGray, 1831
  • Istiurus lesueurii
    A.M.C. Duméril & Bibron, 1837
  • Iguana panamatensis
    Fitzinger, 1843
  • Amphibolurus maculiferus
    Girard, 1857
  • Amphibolurus heterurus
    W. Peters, 1866
  • Amphibolurus branchialis
    De Vis, 1884
  • Physignathus lesueurii
    Boulenger, 1885
  • Intellagama lesueurii
    — Wells & Wellington, 1985

The Australian water dragon (Intellagama lesueurii), [2] which includes the eastern water dragon (Intellagama lesueurii lesueurii) and the Gippsland water dragon (Intellagama lesueurii howittii) subspecies, is an arboreal agamid species native to eastern Australia from Victoria northwards to Queensland. There may be a small introduced population on the south-east coast of South Australia. The Gippsland water dragon is generally the more southern of the two subspecies and the more cold adapted and heat sensitive. Visually distinguishing the Gippsland water dragon from the Eastern water dragon is relatively easy, as long as their skin is reasonably clean and not stained from the water, as identification of the two subspecies depends largely on observable differences in colours and patterns.

Contents

The Gippsland water dragon may be distinguished by its green-blue colour, especially during the breeding season, when this overall colouration is quite distinct. Another key difference is the absence of a prominent dark stripe behind the eye in the Gippsland water dragon, which is characteristic of the Eastern water dragon. The gular region of the two subspecies is also quite different, with Intellagama l. howittii having orange-yellow streaked with darker striping, which is sometimes quite striking, particularly in mature males, whereas Intellagama l. lesueurii typically has a pale, unmarked throat that is sometimes immaculate white in mature males. The belly and chest of Intellagama l. howittii are also quite different to Intellagama l. lesueurii, usually being blackish green, especially in mature males, and the limbs are often quite dark, sometimes even black. Whereas in Intellagama l. lesueurii the chest and belly are usually bright to deep red, particularly in mature males. Intellagama l. lesueurii also have relatively strong dark transverse bars across the back, whereas these dark bars are often much reduced in the Gippsland water dragon.

Etymology

The specific name, lesueurii, is in honor of French naturalist Charles Alexandre Lesueur. [4]

Taxonomy and systematics

The species was first described by John Edward Gray in 1831 as Lophura lesueurii, from a specimen collected by Lesueur & Péron at "Parramatta" or "Port Jackson". [5] [6] Gray listed three species of Lophura: Cuvier's (Lophura Cuvierii Gray), Lesueur's (Lophura Lesueurii Gray), and beautiful (Lophura Concinna Gray, Physignathus Concinnus [a] Cuvier). [5]

In 1845, [7] Gray separated Physignathus (P. concinnus & P. Lesueurii) from Lophura (L. amboinensis [b] & L. Shawii [c] ). The Australian water dragon remained in Physignathus along with the Asian water dragon P. cocincinus until Wells and Wellington published the genus Intellagama in 1985.

The subspecies howitii was described by Frederick McCoy in 1884 as "the Gippsland water lizard". According to his description, it differs from the Queensland subspecies in the proportions of the head and the supra-ocular scales. Its sub-specific epithet commemorates geologist and magistrate Alfred William Howitt, who collected three specimens from the upper reaches of the Buchan River and sent them to McCoy. [8] Two of the specimens cannot be located, [9] the third is D1822 [10] in the collection of the National Museum of Victoria, which was designated the lectotype by Coventry in 1970. [9]

Description

Australian water dragons have long powerful limbs and claws for climbing, a long muscular laterally-compressed tail for swimming, and prominent nuchal and vertebral crests. [11] (A nuchal crest is a central row of spikes at the base of the head. These spikes continue down the spine, getting smaller as they reach the base of the tail.) [12]

Including their tails, which comprise about two-thirds of their total length, adult females grow to about 60 cm (2 feet) long, and adult males can grow slightly longer than one metre (39 inches) and weigh about 1 kg. Males show bolder colouration and have larger heads than females. [13] [14] Colour is less distinct in juveniles. [15]

Species variation

The Australian water dragon is the only species of the genus Intellagama. [2]

There are two subspecies; Intellagama lesueurii lesueurii (eastern water dragon) and Intellagama lesueurii howittii (Gippsland water dragon). The nominate subspecies Intellagama lesueurii lesueurii has a dark band behind its eye and an essentially un-patterned throat that tends towards white and is often immaculate in adult males. Whereas the subspecies Intellagama lesueurii howittii lacks the dark stripe behind the eye and has a patterned throat, which is lightly patterned in females but boldly patterned and coloured in adult males. This patterning usually consists of a dark stripe on either side of its throat, and blotched with orange, yellow or blue towards the centre of the throat. Both subspecies are light greenish grey in overall colour (greener in I. l. howittii), with darker bands running across their back, tail and legs. The water dragon can slowly change skin colour to aid its camouflage. The skin will shed during periods of growth and seasonally to reveal brighter colours in Spring that may aid breeding success.

Behaviour

Head-bobbing behaviour
Eastern water dragon Water Dragon2.jpg
Eastern water dragon
Intellagama lesueurii howitti, Gippsland water dragon basking in Canberra Physignathus lesueurii howittii.jpg
Intellagama lesueurii howitti, Gippsland water dragon basking in Canberra

Australian water dragons are extremely shy in the wild, but readily adapt to continual human presence in suburban parks and gardens. They are fast runners and strong climbers. When faced with a potential predator, they seek cover in thick vegetation, or drop from an overhanging branch into water. They are able to swim totally submerged, and rest on the bottom of shallow creeks or lakes for up to 90 minutes, [12] to avoid detection.

Both males and females display typical agamid behaviour such as basking, arm-waving and head-bobbing. Fast arm-waving signals dominance, while slow arm-waving signals submission. Males are territorial, [11] and in areas of higher population density, males exhibit displays of aggression toward other males including posturing, chasing and fighting.

Breeding

Australian water dragons living in cooler Australian climates hibernate over winter. During spring, usually in early October, the female excavates a burrow about 10–15 cm (3.9–5.9 in) deep and lays between 6 and 18 eggs. [11] The nest is usually in sandy or soft soil, in an area open to sun. When the mother has laid the eggs, she backfills the chamber with soil and scatters loose debris over it. Australian water dragons exhibit temperature dependent sex determination; the sex of the hatchlings is determined by the temperature of the nest site. [12]

When the young are hatched, they stay near the entrance of the burrow for some time before leaving home. When they finally leave the nest, they tend to group together away from the adult population. [13]

Habitat

Basking water dragon in Brisbane's City Botanic Gardens. Basking Australian water dragon in City Botanic Gardens Brisbane Australia.jpg
Basking water dragon in Brisbane's City Botanic Gardens.

As its common name suggests, the Australian water dragon is associated with water and is semi-aquatic. It can be found near creeks, rivers, lakes, and other water bodies that have basking sites such as overhanging branches or rocks in open or filtered sun. The species is very common in the rainforest section of Brisbane Botanic Gardens, Mount Coot-tha in Queensland, and a monument has been built to them there. There is also a significant population in Brisbane's Roma Street Parklands.

There are anecdotal reports of a small colony living on the Sixth Creek in the Forest Range area of South Australia, hundreds of kilometers outside their natural range, which were probably introduced there during the 1980s by a local reptile enthusiast.[ citation needed ]

Predators, threats and diet

Australian water dragons are prey to carnivorous birds, snakes, cats, dogs, and foxes. Nestlings and smaller juvenile water dragons are vulnerable to predation by kookaburras, currawongs, butcherbirds and other carnivorous birds. [16] They are also prone to becoming road kill due to the attraction of warm bitumen and concrete for basking. [16] The Australian water dragon's diet depends on its size. Juveniles and yearlings tend to feed on spiders and small insects such as ants, crickets, and caterpillars. When they get bigger, so does their prey. An adult diet includes small rodents, such as baby mice, other reptiles, frogs, fish, crabs, yabbies, molluscs, worms and eggs, although insects are still the most commonly consumed. [17] [18] [19] [20] [21] [22] Types of vegetation reportedly consumed include figs, lilly-pilly fruits, berries, and other fruits and flowers. [17] [18] [20]

Notes

  1. Cuvier's original spelling was Physignathus cocincinus , after the type locality "cocincine" (Cochin-China).
  2. The name Lophura was already used for a genus of pheasants, the current name is Hydrosaurus amboinensis .
  3. Shawii now considered to be conspecific with amboinensis.

Related Research Articles

<i>Epacris impressa</i> Species of plant

Epacris impressa, also known as common heath, is a species of plant in the heath family Ericaceae. It is native to south-eastern Australia. French botanist Jacques Labillardière collected the species in 1793 and described it in 1805. Four forms have been identified, but no subspecies are recognised. Growing in heathland, shrubland or open forest, it is generally a small shrub around 0.5 to 1 m tall, with small stiff leaves. The red, pink or white tube-like flowers appear from late autumn to early spring. Honeyeater birds, particularly the eastern spinebill, feed upon the nectar of the flowers. It regenerates after bushfire by seed or by resprouting.

<span class="mw-page-title-main">Agamidae</span> Family of lizards

Agamidae is a family of over 550 species of iguanian lizards indigenous to Africa, Asia, Australia, and a few in Southern Europe. Many species are commonly called dragons or dragon lizards.

<i>Pogona</i> Genus of lizards commonly known as bearded dragons

Pogona is a genus of reptiles containing eight lizard species, which are often known by the common name bearded dragons or informally beardies. The name "bearded dragon" refers to the underside of the throat of the lizard, which can turn black and become inflated for a number of reasons, most often as a result of stress, if they feel threatened, or are trying to entice a mate. They are a semiarboreal species, spending significant amounts of time on branches, in bushes, and near human habitation. Pogona species bask on rocks and exposed branches in the mornings and afternoons and sleep at night, making them a diurnal species. Their diet consists primarily of vegetation and some insects. They are found throughout much of Australia and inhabit environments such as deserts, and shrublands.

<i>Ficus macrophylla</i> Species of banyan tree

Ficus macrophylla, commonly known as the Moreton Bay fig or Australian banyan, is a large evergreen banyan tree of the Mulberry Family (Moraceae) native to eastern Australia, from the Wide Bay–Burnett region in the north to the Illawarra in New South Wales, as well as Lord Howe Island where the subspecies F. m. columnaris is a banyan form covering 2.5 acres or more of ground. Its common name is derived from Moreton Bay in Queensland, Australia. It is best known for its imposing buttress roots.

<span class="mw-page-title-main">Central bearded dragon</span> Species of lizard

The central bearded dragon, also known as the inland bearded dragon, is a species of agamid lizard found in a wide range of arid to semiarid regions of eastern and central Australia.

<i>Morelia spilota</i> Species of snake

Morelia spilota, commonly known as the carpet python, is a large snake of the family Pythonidae found in Australia, New Guinea, Bismarck Archipelago, and the northern Solomon Islands. Many subspecies are recognised; ITIS lists six, the Reptile Database six, and the IUCN eight.

<span class="mw-page-title-main">Tiger snake</span> Highly venomous snake native to southern Australia and Tasmania

The tiger snake is a large and highly venomous snake of southern Australia, including its coastal islands and Tasmania. These snakes are often observed and locally well known by their banding, black and yellow like a tiger, although the species can be highly variable in colouration and patterning. All populations are classified within the genus Notechis (Elapidae). Their diverse characteristics have been classified either as distinct species or by subspecies and regional variation.

<i>Limnodynastes dumerilii</i> Species of amphibian

Limnodynastes dumerilii is a frog species from the family Limnodynastidae. The informal names for the species and its subspecies include eastern or southern banjo frog, and bull frog. The frog is also called the pobblebonk after its distinctive "bonk" call, which is likened to a banjo string being plucked. There are five subspecies of L. dumerilii, each with different skin coloration. The species is native to eastern Australia. There has been one occurrence in New Zealand, when tadpoles of the species were found in 1999 and destroyed.

<i>Grevillea rosmarinifolia</i> Species of shrub in the family Proteaceae endemic to New South Wales and Victoria, Australia

Grevillea rosmarinifolia, commonly known as rosemary grevillea, is a species of flowering plant in the family Proteaceae and is endemic to south-eastern continental Australia and naturalised in other parts of the country. It is usually an erect, compact to open shrub with linear, narrowly elliptic or narrowly oblong leaves with the edges rolled under, and loose clusters of pink to red flowers.

<i>Eucalyptus viminalis</i> Species of plant

Eucalyptus viminalis, commonly known as the manna gum, white gum or ribbon gum, is a species of small to very tall tree that is endemic to south-eastern Australia. It has smooth bark, sometimes with rough bark near the base, lance-shaped to curved adult leaves, flower buds in groups of three or seven, white flowers and cup-shaped or hemispherical fruit.

<span class="mw-page-title-main">Chinese water dragon</span> Species of lizard

Physignathus cocincinus is a species of agamid lizard native to southern China and mainland Southeast Asia. It is commonly known as the Chinese water dragon, Indochinese water dragon, Asian water dragon, Thai water dragon, or green water dragon.

<span class="mw-page-title-main">Amboina box turtle</span> Species of turtle

The Amboina box turtle or Southeast Asian box turtle is a species of Asian box turtle widely distributed across Southeast Asia. It is native to the Asian mainland from northeast India, through Bangladesh, Burma and Thailand, across Laos, Cambodia, Vietnam, and Malaysia. It is also found on the archipelagos of Indonesia and the Philippines.

<span class="mw-page-title-main">Lace monitor</span> Species of lizard

The lace monitor, also known as the tree goanna, is a member of the monitor lizard family native to eastern Australia. A large lizard, it can reach 2 metres (6.6 ft) in total length and 14 kilograms (31 lb) in weight. The lace monitor is considered to be a least-concern species according to the International Union for Conservation of Nature.

<span class="mw-page-title-main">Dainty green tree frog</span> Species of amphibian

The dainty green tree frog, also known as the graceful tree frog, is a species of tree frog in the subfamily Pelodryadinae. It is native to eastern Queensland, and north-eastern New South Wales, Australia and ranges from northern Cape York in Queensland to Gosford in New South Wales, with a small and most likely introduced population in Hornsby Heights in Sydney. It is one of two faunal emblems of the City of Brisbane.

<i>Graptemys</i> Genus of turtles

Graptemys is a genus of freshwater turtles containing 14 species, commonly known as map turtles. Graptemys are small to medium-sized turtles that are significantly sexually dimorphic, with females in some species attaining as much as twice the length and ten times the mass as males. Depending on the species, adult males range from 7–16 cm (2.75–6.25 in), adult females 10–29.5 cm (4–11.62 in), and hatchlings 2.5–3.8 cm (1–1.5 in), although some sources indicate female Barbour's map turtles grow to 33 cm (13 in) in length. Most species have a distinctive dark pigmented keel that is often notched or serrated running down the center of the carapace and serrated scutes on the rear margin. The head, neck, and limbs exhibit bold patterns of yellow lines and spots against darker green, olive, or black base colors. The patterns on the head can be important characters in identifying the various species. The common name "map turtle" is derived from the intricate patterns on their shells that are suggestive of topographical maps, although the patterns are more apparent in some species than others, and often become obscure in older specimens. Some species are occasionally called "sawbacks", in reference to the serrated keels on their shell.

<span class="mw-page-title-main">Yellow-spotted monitor</span> Species of reptile

The yellow-spotted monitor, also known as the Argus monitor, is a monitor lizard found in northern and western regions of Australia and southern New Guinea.

<span class="mw-page-title-main">Cape river frog</span> Species of amphibian

The Cape river frog is a species of frog in the family Pyxicephalidae named for the Cape of Good Hope. Formerly, it was placed in the family Ranidae. It occurs widely in the Eastern Cape and Western Cape provinces of South Africa. A newly described species, A. poyntoni, was split from this species in 2013.

<i>Morelia spilota spilota</i> Subspecies of snake

Morelia spilota spilota is a subspecies of carpet python, popularly known as the diamond python. It is a medium to large snake, found in coastal areas and adjacent ranges of south-eastern Australia. It is the most southerly occurring python in the world and is found at higher altitudes than any other species of Australian python.

<span class="mw-page-title-main">Rosenberg's monitor</span> Species of lizard

The Rosenberg's monitor is an Australian species of varanid reptile found in southern regions of the continent. They are large and fast predators with rugged bodies and long tails, having a combined length up to 1.5 metres, that will consume any smaller animal that is pursued and captured or found while foraging. They occur in the Australian Capital Territory, New South Wales, South Australia, Victoria, where it may be rare or locally common, and more frequently observed in Western Australia, where it is sometimes abundant.

<i>Cryptostylis hunteriana</i> Species of orchid

Cryptostylis hunteriana, commonly known as the leafless tongue-orchid is a flowering plant in the orchid family Orchidaceae and is endemic to south eastern Australia. It is leafless but has up to ten green flowers with a more or less erect, dark reddish brown labellum.

References

  1. Tallowin, O.; Hobson, R.; Venz, M.; Wilson, S.; Shea, G.; Vanderduys, E. (2018). "Intellagama lesueurii ". IUCN Red List of Threatened Species . 2018: e.T22566194A22566245. doi: 10.2305/IUCN.UK.2018-1.RLTS.T22566194A22566245.en . Retrieved 19 November 2021.
  2. 1 2 3 Amey, A.P.; Couper, P.J.; Shea, G.M. (2012). "Intellagama lesueurii (Gray, 1831), the correct binomial combination for the Australian Eastern Water Dragon (Sauria, Agamidae)" (PDF). Zootaxa. 3390 (1): 65–67. doi: 10.11646/zootaxa.3390.1.6 .
  3. Species Intellagama lesueurii at The Reptile Database www.reptile-database.org.
  4. Beolens B, Watkins M, Grayson M (2011). The Eponym Dictionary of Reptiles. Baltimore: Johns Hopkins University Press. xiii + 296 pp. ISBN   978-1-4214-0135-5. (Physignathus lesueurii, p. 156).
  5. 1 2 Gray, John Edward (1831). "A Synopsis of the Species of Class Reptilia". In Griffith, Edward (ed.). A Classified Index and Synopsis of the Animal Kingdom arranged in Conformity with its Organisation by the Baron Cuvier. Volume IX, Reptilia. London: Whittaker & Co. p.  s. 60.
  6. "Spécimen MNHN-RA-0.392: Intellagama lesueurii (Gray, 1831)". science.mnhn.fr. Muséum National de Histoire Naturelle. Retrieved 24 February 2023.
  7. Gray, John Edward (1845). Catalogue of the Specimens of Lizards in the Collection of the British Museum. London: Trustees of the British Museum. (Edward Newman, printer). pp. 247–248.
  8. McCoy, Frederick (1884). "Physignathus leusueurii (Gray), Var. howitii (McCoy)". Natural History of Victoria. Prodromus of the Zoology of Victoria, or, Figures and Descriptions of the Living Species of All Classes of the Victorian Indigenous Animals. Decade IX. Melbourne: Government Printer: 7–10, plate 81.
  9. 1 2 Coventry, A.J. (1970). "Reptile and amphibian type specimens housed in the National Museum of Victoria". Memoirs of the National Museum of Victoria. 31: 115–124. doi:10.24199/j.mmv.1970.31.13.P. l. howitii is on page 117
  10. "Specimen D 1822: Physignathus lesueurii howittii McCoy, 1884". Museums Victoria Collections. Retrieved 24 February 2023.
  11. 1 2 3 Maruyama, Kaori; Langkilde, Tracy, Physignathus lesueurii (PDF), James Cook University, archived from the original (PDF) on 2008-07-27, retrieved 2009-05-21
  12. 1 2 3 Australian National Botanic Gardens: Research into Water Dragons Archived June 30, 2007, at the Wayback Machine
  13. 1 2 "Critters of Calamvale Creek: Eastern Water Dragon". Calamvalecreek.awardspace.com. Archived from the original on 2011-07-25. Retrieved 2013-07-09.
  14. "Australian Museum Online: Wildlife of Sydney". Archived from the original on 2007-06-12. Retrieved 2007-07-02.
  15. "Critters of Calamvale Creek: baby Eastern Water Dragon". Calamvalecreek.awardspace.com. Archived from the original on 2011-07-25. Retrieved 2013-07-09.
  16. 1 2 Australian National Botanic Gardens: Predators of Water Dragons Archived November 21, 2008, at the Wayback Machine
  17. 1 2 "Australian Water Dragon".
  18. 1 2 "Eastern Water Dragon".
  19. "Eastern Water Dragon". 23 September 2020.
  20. 1 2 "Eastern Water Dragon - the Animal Facts - Appearance, Diet, Habitat".
  21. "Australian Water Dragon Care Sheet".
  22. "Water Dragon". 20 April 2020.

Further reading