Little waterfall frog
Common name: little waterfall frog, armoured mistfrog
Scientific name: Litoria lorica
Family: Hylidae (tree frogs)
Conservation status: This species is listed as Endangered in Queensland (Nature Conservation Act 1992)and Critically Endangered nationally (Environment Protection and Biodiversity Conservation Act 1999). It is considered a low priority under the Department of Environment and Resource Management Back on Track species prioritisation framework.
Description
A medium sized frog with males between 29-33 mm and females 33-37 mm long (Davies & McDonald 1979). The dorsal surface is uniform grey or grey-brown. The ventral surfaces are white, variably peppered with dark brown on the throat. The skin is finely tubercular dorsally, prominently so on the upper eyelids and in the tympanic region. The lower surfaces are granular on the thorax, abdomen and backs of the thighs, but smooth elsewhere.
The finger and toe discs are well developed. The fingers have basal webbing and the toes are fully webbed. The hands have an enlarged prepollex. Males have black spiny nuptial pads and accessory spines on the chest. The head is evenly rounded, with snout truncate and nostrils terminal. The tympanum is small and indistinct. The vocal sac is absent (Davies & McDonald 1979).
Habitat and distribution
The little waterfall frog is found on boulders in the splash zone near turbulent, fast-flowing water in upland rainforest and adjacent sclerophyll forest (Davies & McDonald 1979, Hoskin & Hero 2008).
This species is only known from five localities in north-east Queensland: Thornton Peak, Mt Pieter Botte, Mossman Gorge and Carbine Tableland. Only the recently discovered Carbine Tableland population is still extant (R. Puschendorf pers. comm. 2008, Hoskin & Hero 2008). The species has not been found at the remaining four sites since 1991, despite ongoing survey efforts. It is found at latitude between 16&186; 7' and 16&186; 10'; and longitude between 145&186; 20' and 145&186; 22'.
Life history and behaviour
The call of this species is unknown. Females carry large unpigmented eggs (2.3 mm in a female paratype) (Davies & McDonald 1979). The tadpoles, though undescribed, are probably similar to those of the waterfall frog Litoria nannotis - with large suctorial mouths for feeding in fast-flowing streams (Davies & McDonald 1979).
Threatening processes
The little waterfall frog is one of seven species of frogs occurring in the upland rainforest streams of north-eastern Queensland which have undergone rapid and substantial population declines in the last decade (Richards et al 1993).
The causes of the decline remain unknown Richards et al (1993) found no obvious evidence that drought, floods, habitat destruction or pollution by pesticides, inorganic ions or heavy metals were responsible for the population declines. Current research is examining the possibility that a disease may have caused the decline of the stream dwelling frogs of the Wet Tropics. Information on disease investigations and management can be located at the James Cook University website. Chytrid fungus has been found on little waterfall frogs on the Carbine Tableland, Mt Lewis Forest Reserve (R. Puschendorf pers. comm. 2008).
Recovery actions
The recovery plan makes the following management recommendations for the conservation of stream-dwelling frogs of the Wet Tropics bioregion.
- Monitor historical localities to detect recovery.
- Investigate disease in preserved animals and species occupying similar habitat.
- Develop and refine husbandry techniques for rainforest steam dwelling frogs.
- Train park staff and community volunteers in identification of this species.
- Implement monitoring by park staff of select locations within the national park estate where the little waterfall frog formerly occurred.
Related information
Davies, M and McDonald, KR 1979. A new species of stream-dwelling hylid frog from northern Queensland. Transactions of the Royal Society of South Australia 103(7): 169-176.
Hoskin. CJ and Hero JM 2008. Rainforest frogs of the Wet Tropics, northeast Australia. Griffith University, Gold coast 84pp.
Ingram, GJ and McDonald, KR 1993. an update on the decline of Queensland's frogs. Pp 297-303 In Lunney, D. and Ayers, D. (eds), `Herpetology in Australia. A diverse discipline'. (Royal Zoological Society of New South Wales; Mosman). 414pp.
McDonald, KR 1992. Distribution patterns and conservation status of north Queensland rainforest frogs. Conservation Technical Report 1., Queensland Department of Environment and Heritage, Brisbane.
Northern Queensland threatened Frogs Recovery Team. 2001. Recovery plan for the stream-dwelling rainforest frogs of the Wet Tropics biogeographic region of north-east Queensland 2000-2004. Report to Environment Australia, Canberra. Queensland Parks and Wildlife Service, Brisbane.
Richards, SJ, McDonald, KR, Alford, RA 1993. Declines in populations of Australia's endemic tropical rainforest frogs. Pacific Conservation Biology 1:66-77.
Last updated 14 July 2011