Description
Litoria myola males are between 35 to 45 mm in length and are 2 to 5 grams in weight, whereas the females are 57 to 69 mm in length and are 9 to 19 grams in weight. Litoria myola has a robust, dorsoventrally flattened head that is slightly wider than the rest of its body. Its snout is rounded and is slightly truncated. The eyes are large with horizontal, cylindrical pupils. The tympanum is clearly visible. Males have vocal sacs. The body is slender with a urostyle that ranges anywhere from indistinct to moderately visible. The skin on the ventrum is rough, granular while the skin on the dorsum is smooth to slightly granular. Some individuals have dorsal tubercles. Distinct skin folds that originate posteriorly to the eye and terminate in the mid-body are present. The forelimbs are robust, especially in males and have distinct ridges that run into hands and where they become less distinct. There is moderate webbing between the long fingers with a webbing formula of I 2 – 2½ II 1½ – 2½ III 2 – 2 IV. The relative length lengths are 3 > 4 > 2 > 1. The fingers disks are round and expanded. Males have nuptial pads that are located on first finger. The hind limbs are slender and long, and have highly reduced tubercles. The toes have full webbing with a webbing pattern of I 1½ – 2 II 1 – 2 III 1 – 2 IV 2 – 1 V, round disks that are smaller than finger disks, and have a relative length pattern of 4 > 3 > 5 > 2 > 1 (Hoskin 2007).

Litoria myola co-occurs with the northern lineage of L. genimaculata, in the Kuranda region of Queensland, Australia and is very similar in coloration, body shape, and pattern. Litoria myola can be distinguished from L. genimaculata by its faster, shorter call and faster, higher frequency mating call. Litoria myola males are typically smaller in body size than L. genimaculata males. Litoria myola is also similar to L. eucnemis but can be differentiated by range and call (Hoskin 2007). Litoria myola and L. serrata are also very similar in appearance, however, L. myola can be distinguished by the irregular bands on its hindlimbs (Cogger 2014).

The dorsal coloration of preserved specimens varies from blotched brown, spotted brown, and gray. Blotched individuals have an hourglass-shaped pattern, with pale shoulders, lower back, and forehead. Pale triangular patches may also occur on the nares and between the eyes. Dark, uneven bars often occur on the hindlimbs. The ventral surface is a cream color and the chin and throat is often colored with light speckling. The underside of the lower hindlimbs and feet, the groin, and thighs are often colored with brown mottling. The toe discs are typically cream to mottled brown (Hoskin 2007).

Live specimens have varying dorsal coloration and patterning. Specimens range from brown, tan, mottled gray, brown, to blotched green and brown. The ventral surface ranges from white to cream. The throat of male individuals ranges from light brown to light gray, with some dark speckling on the chin. The iris may range from cream to gray, with fine, brown veins covering its surface. Pupils are bordered by dark stripes that run horizontally across the eye (Hoskin 2007).

The species exhibits distinct sexual dimorphism in size, but not in coloration or morphology. Females are typically 1.6 times the snout-vent length of and 4.5 times the weight of males (Hoskin 2007).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Australia

View distribution map in BerkeleyMapper.

The range of Litoria myola is located in the Kuranda area of Northeastern Queensland, Australia at elevations from 320 - 360 m asl. They can only be found in small sections of 13 streams that drain into the Barron River in rainforest habitat (Hoskin 2007, Hoskin 2008).

Life History, Abundance, Activity, and Special Behaviors
Litoria myola is a rare, nocturnal species. Females are mostly arboreal except when breeding, when they congregate along streams. Males are generally found along streams. Aquatic individuals are associated with streams, riffle zones, and small waterfalls (Hoskin 2007).

Males call to females, as well as perform warning calls to other males nearby. Their call is characterized as short and fast. The mating call has a duration of 0.85 seconds, a rate of 8.8 notes per second and frequency of 1.79 kHz. Threatening calls are slower and longer. Males are also known approach one another to wrestle when they call aggressively. When attracting mates, males perch in vegetation about 0.30 - 1.5 m off the ground (Hoskin 2007).

The breeding season occurs during the rainy summer months between October and March. Males use axillary amplexus. Larvae prefer stream habitats and take approximately 2 months until they are fully metamorphosed (Hoskin 2007)

The feeding habits of adults and larvae are unknown. Closely related species have a diet of invertebrates including insects and arthropods. Additionally, no predators or antipredator behavior is reported for the species. However, L. myola is parasitized by the Dipteran fly, Batrachomyia species (Hoskin 2007).

The species is not not aposematically colored, but may exhibit some crypsis, as their typically brown to mottled brown coloration could help them blend in with surrounding vegetation (Hoskin 2007).

Trends and Threats
This species is declining due to a number of threats such as loss of rainforest habitat, invasive predators, declining water quality, increased sedimentation, change in flow rates and timing, chytrid outbreaks, pollution of stream habitat, and drought. The species may also be threatened by hybridization and competition with L. genimaculata. These threats are especially deleterious because L. myola has a very limited range that occurs in an unprotected rainforest and naturally small population sizes (Hoskin 2008, Curtis et al. 2012). The small population size also makes this species especially vulnerable to local disturbances such as drought (Hoskin 2007). Because at the majority of sites, the species' density is low and affected by rainfall conditions, this species is listed as “Critically Endangered” on the IUCN Red List (Hoskin 2008).

Litoria myola can be found in one protected area and it is recommended that management for the species be focused on the protection and restoration of the stream habitat and surrounding rainforest. It is also recommended that the moving of L. moyla and L. genimaculata be prohibited to prevent more than limited hybridization of the two species (Hoskin 2008).

Possible reasons for amphibian decline

General habitat alteration and loss
Habitat modification from deforestation, or logging related activities
Urbanization
Disturbance or death from vehicular traffic
Prolonged drought
Secondary succession
Dams changing river flow and/or covering habitat
Subtle changes to necessary specialized habitat
Habitat fragmentation
Local pesticides, fertilizers, and pollutants
Predators (natural or introduced)
Introduced competitors
Disease
Loss of distinctiveness through hybridization
Climate change, increased UVB or increased sensitivity to it, etc.

Comments
The species authority is: Hoskin, C.J. (2007). ''Description, biology and conservation of a new species of Australian tree frog (Amphibia: Anura: Hylidae: Litoria) and an assessment of the remaining populations of Litoria genimaculata Horst, 1883: systematic and conservation implications of an unusual speciation event.'' Biological Journal of the Linnean Society, 91(4), 549-563.

Based on analysis of mitochondrial DNA (COI) and nuclear loci, L. myola was reveals to be nested within the southern lineage of L. genimaculata. However, L. myola is genetically distinct from the northern lineage of L. genimaculata in Kuranda with whom it co-occurs. Hybridization experiments showed that male L. myola and southern lineages of L. genimaculata can be successfully hybridized with females from the northern lineage, but the reverse produced larvae that died in the early stages. Call experiments show that females have a strong preference for their own species call, but 0 – 1.4% of individuals at sites where the species co-occur are hybrids (Hoskin 2007).

The species gets its name from the Myola region in which it occurs. Myola is thought to be an aboriginal name, but its origins are unclear. The common name of the species is the Kuranda Tree Frog (Hoskin 2007).

References

Cogger, H.G. (2014). Reptiles and Amphibians of Australia (7th ed.). CSIRO Publishing, Collingwood.

Curtis, L.K., Dennis, A.J., McDonald, K.R., Kyne, P.M., and Debus S.J. (2012). ''Amphibians: Kuranda Tree Frog.'' Queensland's Threatened Animals. Curtis, L.K., Dennis, A.J., McDonald, K.R., Kyne, P.M., and Debus S.J. , eds., CSIRO Publishing, 156-157.

Hoskin, C. (2008). ''Litoria myola.'' The IUCN Red List of Threatened Species 2008: e.T136003A4225804. http://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T136003A4225804.en. Downloaded on 19 February 2017.

Hoskin, C.J. (2007). ''Description, biology and conservation of a new species of Australian tree frog (Amphibia: Anura: Hylidae: Litoria) and an assessment of the remaining populations of Litoria genimaculata Horst, 1883: systematic and conservation implications of an unusual speciation event.'' Biological Journal of the Linnean Society, 91(4), 549-563.

Species Account Citation: AmphibiaWeb 2017 Litoria myola: Kuranda Tree Frog <https://amphibiaweb.org/species/6958> University of California, Berkeley, CA, USA. Accessed Dec 28, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 28 Dec 2024.

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