Description
Litoria mira are robust frogs, with a male snout-urostyle length range of 59.5 - 70.8 mm and a female range of 66.7 - 79.6 mm. The head is almost as wide as it is long. They have small but prominent eyes with moderately-sized, horizontal pupils. A paratoid gland is present, but not prominent. The skin is smooth on the dorsal and lateral surfaces of the body, head, throat, anterior abdomen, arms, and lower extremities of legs. However, the skin on the upper legs and posterior abdomen is wrinkled. The arms and legs are robust, and the fingers and toes share several commonalities including webbing, circummarginal grooves, prominent discs and subarticular tubercles (Oliver et al. 2021). For more description please see Oliver et al. 2021.

Litoria mira is differentiated from other Litoria by their somewhat large size, relatively narrow head, and brown, patternless dorsal coloration. Other features include a small violet patch at the postero-ventral edge of the eye, a lack of a white stripe on the lip, a lack of white/yellow lateral folds on the limbs, and a paratoid gland that is present but not prominent (Oliver et al. 2021). For more comparisons please see Oliver et al. 2021.

In preservative, specimens have a dark brown dorsal coloration with the upper hind limbs and digits being slightly more pale. The ventral coloration is a pale buff, with a swath of darker brown on the throat, and patches of lighter brown on the torso, lower forelimbs, hind limbs, and toes. In life, L. mira has a very similar coloration as in preservative but pigmentation is more scattered and lighter brown in general. They also feature a small violet patch near the eye (Oliver et al. 2021).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Papua New Guinea

View distribution map in BerkeleyMapper.

Litoria mira is distributed across several provinces north and south of the Central Cordillera in New Guinea. They may also be found in northern Papua New Guinea, although, at the time of the species description, the suspected specimens from this area had yet to be cataloged. They tend to live in both disturbed and undisturbed lowland swamp forests and swampy rainforests. It’s believed that they may exist more widely across New Guinea but in inaccessible lowland swamp forest regions based on low genetic variation between the samples collected (Oliver et al. 2021).

Life History, Abundance, Activity, and Special Behaviors
Liitoria mira have an advertisement call that is a series of deep, raspy barks, very similar to that of L. caerula. The initial call in a series is the quietest, and every bark that follows increases in amplitude except for the last. Calls can be from 0.10 to 0.17 seconds long, and consist of 18 - 23 pulses emitted at a rate of about 150 pulses per second (Oliver et al. 2021).

Comments

Phylogenetic relationships:

Maximum Likelihood analysis of NADH dehydrogenase subunit 4 and a small fragment of tRNA placed L. mira in the Litoria caerula group. Within this clade the lowland forest-dwelling L. mira appears to be a sister lineage to the savannah-dwelling lineages of L. caerulea, L. gilleni and L. splendida (Oliver et al. 2021).

Etymology:

The species epithet, “mira” is derived from the Latin, “mirium” which means “surprised” or “strange”, and L. mira was so named after the researchers’ surprise at finding an undescribed member of L. caerula group, which is mostly found in Australia, in New Guinea (Oliver et al. 2021).

References

Oliver PM, Rittmeyer EN, Torkkola J, Donnellan SC, Dahl C, Richards SJ. “Multiple trans-Torres Strait colonisations by tree frogs in the Litoria caerulea group, with the description of a new species from New Guinea," Australian Journal of Zoology, 68(1), 25-39 [link]

Species Account Citation: AmphibiaWeb 2022 Litoria mira: Chocolate tree frog <https://amphibiaweb.org/species/9416> University of California, Berkeley, CA, USA. Accessed Apr 1, 2023.

Citation: AmphibiaWeb. 2023. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 1 Apr 2023.

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