Description
Allobates juami is a species of nurse frog. The snout-vent length for males is 17.0 – 18.2 mm and for females is about 17.5 - 18.5 mm. The head is wider than it is long and the eye diameter is bigger than the distance taken from the eye to the nostril of the frog. This species has maxillary teeth and a long tongue. It also has a single vocal sac. It has a flat granular skin texture in the dorsal posterior part of the body that scatters from the tympanum to the urostyle. There is no metacarpal ridge found on this frog. The relative finger lengths are IV < II < I < III. The digital scutes on the dorsal side are paired and no distal tubercle is present on the fourth finger. The finger discs on all fingers are expanded. The fingers also do not have any webbing. A curved tarsal keel is present. The relative toe lengths are I < II < V < III < IV. The discs on toes I to IV are weakly expanded, while the disc on toe V is much more expanded. There is light webbing on toes III and IV. More comprehensive description can be found in Simoes et al. 2018.

This species differs from other species of nurse frogs because the males lack dark pigments on their ventral side. Their dorsal color pattern is mainly a dark brown color with a light brown snout, they have light-colored dorsolateral and ventrolateral stripes on the body, they have a light-colored paracloacal blemish, no presence of melanophores on the chin area, and the snout-vent length is different from other nurse frog species. Allobates juami also emits advertisement calls as trills that are composed of a larger number of notes compared to those of other nurse frog species. Allobates juami and Allobates conspicuus may be easily mistaken for one another but the upper backside of A. conspicuus is a much lighter brown color than A. juami. Allobates conspicuus also has dermal fringes on its toes, which A. juami does not have. Compared to other Allobates species, A. juami emits calls that are composed of longer numbers of notes. More comprehensive diagnosis can be found in Simoes et al. 2018.

This species exhibits cryptic external coloration. In preservative, the dorsal part of the body is a solid dark brown color. The anterior part of the body is light brown in color starting from the snout tip to the eye. The posterior part of the body is also light brown around the urostyle area. A light pale stripe is found on the dorsolateral region of this frog. There is a dark brown stripe present on the sides of the body that starts from the snout tip and ends at the groin. Under the dark brown stripe is a very narrow white stripe that starts from the eye and ends at the groin. The ventrum is white to translucent with a narrow, pale ventrolateral strip and a scattering of iridescent patches over the chin and between the pectoral region and posterior abdomen (Simoes et al. 2018).

In life, the dorsum is similar in coloration as in preservative. The ventral side of the body is yellow in color and merges with the narrow, iridescent white stripe ventrolateral strip. The abdomen is significantly paler in color. The throat coloration varies depending on the sex. In females, the throat is mainly yellow. In males, the throat can be pink or semitransparent in color. The dorsal part of the arm is light brown and may have very tiny spotting marks. There is a light pale paracloacal blemish that blends in with the light brown color present on the thigh. The scutes present on the toe discs can either be white or black. The eyes have a dark iris and golden ring around the pupils. More comprehensive coloration can be found in Simoes et al. 2018.

Most of the variation comes from the throat color between the males and females. While females have a yellow throat, males have a pink to semitransparent colored throat (Simoes et al. 2018).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Brazil

View distribution map in BerkeleyMapper.

Allobates juami inhabits the Juami River basin in the northwestern Brazilian Amazon at an elevation of 87 m asl. This is a mainland forest habitat on the east side of the Juami River found within the Juami-Japura Ecological Station of the Amazon Rainforest. This species lives in seasonally flooded forest areas of the Brazilian Amazon where leaf litter piles up. They mainly occupy dry ground. They are currently only known to be from this area of the Juami River (Simoes et al. 2018).

Life History, Abundance, Activity, and Special Behaviors
Allobates juami have cryptic external coloration patterns to help them camouflage well with the layers of leaf litter they live around in the forest. They associate little with forest streams in the Juami-Japura Ecological Station and have been found to stay about 10 meters away from the stream (Simoes et al. 2018).

This species is diurnal meaning that the males do their vocalization calls during the day. The calls consist of short notes composed of trills that last about 2.5 to 5.0 seconds. Each trill containing about 65 notes that last about 0.03 seconds. Their average pace of note emissions are about 13 notes per second. The notes of the calls have an ascending frequency with each peak frequency being about 5.0 kHz. The intervals of silence between each note in the trills lasts about 0.03 seconds on average (Simoes et al. 2018).

Trends and Threats
The trends and threats are unknown, but they do occur in an area in the northwestern Brazilian Amazon where no human populations have been reported (Simoes et al. 2018).

Comments

Based on neighbor joining analyses on 16S rDNA, A. juami is more closely related to A. insperatus. Together they are sister to the clade composed of A. conspicuus and A. subfolionidificans (Simoes et al. 2018).

The species epithet, “juami”, refers to the locality of where the species was found, the Juami River (Simoes et al. 2018).

This species is the 27th Allobates species to be reported in Brazil (Simoes et al. 2018).

References

Simoes, P. Gagliardi-Urruta, G., Rojas-Runjaic, F.J.M., Castroviejo-Fisher, S. (2018). "A new species of nurse-frog (Aromobatidae, Allobates) from the Juami River basin, northwestern Brazilian Amazonia." Zootaxa, 4387(1), 109-133. [link]

Species Account Citation: AmphibiaWeb 2021 Allobates juami: Nurse Frog <https://amphibiaweb.org/species/8785> University of California, Berkeley, CA, USA. Accessed Nov 21, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 21 Nov 2024.

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