The Lesueur's frog (Ranoidea lesueuri), also commonly known as the Stony Creek frog or Lesueur's tree frog, is a species of arboreal frog native to northern and eastern Australia. It belongs to the family Pelodryadidae, which includes the Australasian tree frogs.
Taxonomy and Etymology
- Scientific Name: Ranoidea lesueuri (formerly Litoria lesueuri)
- Family: Pelodryadidae
- Genus: Ranoidea
- Species: R. lesueuri
The species was named in honour of Charles Alexandre Lesueur, a French naturalist and explorer who was part of Nicolas Baudin's expedition to Australia in the early 19th century. Genetic studies have led to its reclassification from the genus Litoria to Ranoidea.
Description
Lesueur's frog is a medium-sized frog, typically growing to a length of 4 to 6 cm (1.6 to 2.4 inches). Its appearance is highly variable across its wide distribution, but some common characteristics include:
- Colouration: The dorsal (upper) surface can range from shades of brown, grey, olive-green, or a combination of these, often adorned with darker blotches or irregular patterns. A distinct dark stripe usually extends from the snout, through the eye, and over the tympanum (eardrum) to the shoulder.
- Ventral Surface: The underside is typically white or cream.
- Skin: The skin is generally smooth.
- Snout: It possesses a moderately pointed snout.
- Limbs: The legs are relatively long and slender, with well-developed toe pads, though it is less arboreal in habit compared to many other Ranoidea species and is frequently found on rocks.
- Tympanum: The tympanum is large and distinct.
Distribution and Habitat
Lesueur's frog has a very extensive distribution across northern and eastern Australia. Its range includes:
- The Kimberley region of Western Australia.
- Across the Northern Territory.
- Throughout Queensland.
- Down to northeastern New South Wales.
This species is primarily associated with permanent or semi-permanent water bodies, favouring rocky streams, rivers, and sometimes larger ponds or dams. It is often found sheltering among rocks, boulders, or vegetation along the water's edge, reflecting its common name "Stony Creek frog."
Ecology and Behaviour
- Nocturnal: Lesueur's frog is predominantly nocturnal, emerging at night to feed and breed.
- Diet: Its diet consists mainly of various invertebrates, including insects and other small arthropods.
- Breeding: Breeding typically occurs during the warmer months, often triggered by rainfall events. Males call from concealed positions near water, such as under rocks or amongst vegetation. The call is described as a series of short, unhurried, "wark-wark-wark" or "crek-crek-crek" notes.
- Reproduction: Eggs are laid in still or slow-moving water, often attached to submerged vegetation or rocks. The tadpoles are benthic (bottom-dwelling) and feed on algae and detritus.
Conservation Status
The Lesueur's frog is classified as Least Concern by the International Union for Conservation of Nature (IUCN). This status reflects its wide distribution, presumed large population, and its occurrence in numerous protected areas. While some localised threats like habitat degradation from land clearing or altered water regimes may exist, these are not currently considered to impact the species significantly across its entire range.