The northern dwarf tree frog (''Litoria bicolor'') is a small species of

tree frog A tree frog (or treefrog) is any species of frog that spends a major portion of its lifespan in trees, known as an arboreal state. Several lineages of frogs among the Neobatrachia have given rise to treefrogs, although they are not closely rela ...

native to northern Australia, from the Kimberly region of

Western Australia Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...

to Bowen,

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 , establishe ...

, and

Aru Islands The Aru Islands Regency ( id, Kabupaten Kepulauan Aru) is a group of about 95 low-lying islands in the Maluku Islands of eastern Indonesia. It also forms a regency of Maluku Province, with a land area of . At the 2011 Census the Regency had a ...

of Indonesia. These small frogs are also commonly called sedge frogs. The population occurring in Indonesia may not be ''L. bicolor'', and research on call structure or genetics is needed to confirm its taxonomic status.

Description

Litoria bicolor The northern dwarf tree frog is small, slender tree frog growing up to 30 mm in length. It has a green dorsal surface and a thin bronze dorsolateral band that begins at the eye.Barker, J., Grigg, G. C., and Tyler, M. J. (1995). ''A Field Guide to Australian Frogs.'' Surrey Beatty and Sons, New South Wales. There is often a central bronze band running along the spine of the back. A narrow white stripe runs from under the eye, at the corner of the mouth, to the base of the arm. The ventral surface is cream or yellowish, with golden reflections on the thighs and groin area. The male throat is speckled with a darker color. The skin is granular in the belly and femoral region, but smooth elsewhere. The iris of the eye is golden, the eardrum is distinct, the vomerine teeth are absent, and there is a strong pectoral fold. There are disks on the fingers and toes, the fingers are slightly webbed, and the fringed fingers are about three-quarters of a palm. There is an inner but not outer metatarsal tubercle, and the second finger is longer than the first.

Ecology and behaviour

Most abundant in grassland or marshy areas, but also occurs along permanent or semi-permanent streams, billabongs and floodplains. Breeding starts with summer rains and 10-24 eggs are laid on submerged vegetation in temporary pools. Males call from around the breeding site from elevated positions. The call is a "wree-e-eck pippip" with the second part of the call starting before the first part finishes. Tadpole metamorphosis takes 70 to 80 days.

Similar species

The northern dwarf tree frog is a member of the ''Litoria fallax'' complex, which includes also includes the eastern dwarf tree frog (''L. fallax''), Cooloola tree frog (''L. cooloolensis'') and Olongburra frog (''L. olongburensis''). All these species are similar in appearance (small, <30 mm and similar body shape) and have a similar call (ratchet-like "wreek"). The northern dwarf tree frog is most similar to the eastern dwarf tree frog. They occur together along the east coast of

. ''L. bicolor'' can be distinguished from ''L. fallax'' most readily by the presence of a bronze stripe that runs down the flanks and the call. The first phase of the call of ''L. bicolor'' is twice as long as that of ''L. fallax''.

References

{{Taxonbar, from=Q917813 Litoria Amphibians of Western Australia Amphibians of the Northern Territory Amphibians of Queensland Amphibians described in 1842 Taxa named by John Edward Gray Frogs of Australia