Description
Ranitomeya yavaricola is a small, semi-smooth-bodied frog described from two males and one female along with measurements of 12 additional specimens that were not collected. Their overall snout-vent length ranged from 15.2 - 17.7 mm, with males ranging from 15.2 - 17.2 mm and two females with snout-vent lengths of 16.8 and 17.7 mm. There is no distinction between male and female, except that the females tend to be a little bit broader and the males have vocal slits and a slight subgular pouch. The relative finger lengths are III > IV > II > I and the relative toe lengths are IV > III > V > II > I. Each digit has an expanded disc corresponding to the digit length, with the longest finger having the widest disc. There is no webbing on the toes (Perez-Peña et al. 2010). For a more complete description, please see Perez-Peña et al. 2010.

DIAGNOSIS:

Ranitomeya yavaricola can be differentiated from other Ranitomeya mainly by coloration and patterning. Specifically, in having solid rusty gold-colored limbs, non-uniform stripes and spots along the dorsal part of the frog, and two light blue spots on the ventral surface of the upper thighs. In contrast, R. flavovittata has yellow spotting/striping and black limbs with light blue markings, no spots on the upper thighs, and a yellow stripe instead of light-bluish green where the limbs attach. Ranitomeya vanzolinii has yellow spotting and light blue markings on black limbs and also lacks spots on the upper thighs (Perez-Peña et al. 2010).

COLORATION:

In life, the background body coloration is black with unique, bright, light bluish-green markings of stripes and/or dots along their back. Each individual has facial markings, especially in between the eyes. A single dot is positioned in the inner corner of each eye. These patterns extend to the upper part of the shoulder and lower back, but do not go all the way down the fore- or hind limbs. The limbs are a rusty-gold coloration and there is a light bluish-green striping along the sides of the body where the limbs attach. The ventrum is almost entirely bluish-green with unusual black spotting. All colors, besides the solid black base, are vibrant and have a metallic quality. The irises are black. In preservative, the vibrance of the frog diminishes, the light bluish-green turns gray while the rusty-gold on the limbs turns brown (Perez-Peña et al. 2010).

VARIATION:

Sexual dimorphism is only notable by a slight size difference, with females tending to be larger, and vocal slits and a slight subgular pouch in males. Gravid females also are wider. Individuals have quite a lot of variation in patterning ranging from mostly dotted markings, distinct stripes surrounded by dots, and some stripes that do not extend fully along the back. The patterning may have spaces in between them (Perez-Peña et al. 2010).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Peru

View distribution map in BerkeleyMapper.

Ranitomeya yavaricola is found in a primary forest near Lago Preto, an oxbow lake, in northeastern Peru. Lago Preto is at the junction of two rivers, the Rio Yavari River and the Rio Yavari-Mirin River. They occur in low elevation areas at 120 meters (Perez-Peña et al. 2010, IUCN 2020). Their preferred habitat types include seasonally flooded forests, year-round swamps, and upland “terra firme.” These habitat areas contain large canopies with sparse understory (Perez-Peña et al. 2010).

Life History, Abundance, Activity, and Special Behaviors
Ranitomeya yavaricola is the most abundant frog species in the Lago Preto area. Its preferred type of habitat is tree-filled forests with seasonal flooding that have swamps, or upland “terra firme”. The dominant tree species in this area belong to the Fabaceae, Bombacaceae, and Moraceae families (Perez-Peña et al. 2010).

This dart-poison frog has a shy nature. They are rarely seen but have been found hiding in leaf piles, and on the leaves of tree palms, bromeliads, and the branches of trees that had fallen. When alarmed, adults escape to the leaf litter or in the roots of plants (Perez-Peña et al. 2010).

Adults males call sporadically, with peaks in the early morning and late afternoon, from terrestrial palms. At temperatures between 24.5 - 26 °C, their calls are described as a “short trill” with a dominant frequency between 5,400 - 6,000 Hz and a pulse rate of 0.031 - 0.032 pulse/ms with 2 - 7 note repeats for 0.63 - 0.88 seconds. Each note also has 20 - 27 pulses (Perez-Peña et al. 2010, Brown et al. 2011).

Reproduction occurs in arboreal bromeliads where the females lay their eggs for the males to fertilize without amplexus (Perez-Peña et al. 2010, Brown et al. 2011).

Ranitomeya yavaricola is potentially found in sympatry with R. flavovittata and R. ventrimaculata (Perez-Peña et al. 2010).

Larva

At Gosner Stage 25, a single tadpole had a total length of 12.5 mm, a body length of 4.7 mm, and a tail length of 7.8 mm. The overall body shape is rounded with a round snout when viewed from above. The nostrils are located half-way between the eyes and the snout-tip and directed dorsolaterally. The eyes are positioned dorsally and oriented laterally. The mouth placement is anteroventral, and consists of an emarginate oral disc with round papillae on the posterior labium. The oral labia form free flaps. The jaw sheaths are serrated and the labial tooth rows formula is 2(2)/3[1]. The spiracle is sinistral and the vent is dextral. The ventral tail fin starts at the base of the tail whereas the dorsal tail fin starts at the same level as the vent. The tail tapers to a point (Perez-Peña et al. 2010).

In life, the head is light gray and the dorsum is weakly transparent with brown mottling. The ventrum is transparent, with visible internal organs and irregular faint red flecks that is particularly dense around the mouth and nostrils. The papillae are white. The eyes are black. The tail musculature has brown mottling and the fins are transparent. In preservative, the red flecks become brown and the eyes become white. Otherwise the coloration is similar (Perez-Peña et al. 2010).

This species has indirect development and hatches 10 - 14 days after being laid as detritivorous/carnivorous brown tadpoles. The tadpoles grow to be carnivorous, aposematic adults (Perez-Peña et al. 2010, Brown et al. 2011).

Tadpoles live in phytotelm bromeliad, which grow in clumps of 2 - 6 plants, with approximately 30 ml of water in the plants. Tadpoles live in these bodies of water during their development, lasting about 2 months, and leave to sexually mature outside of the phytotelm and pools (Perez-Peña et al. 2010).

Trends and Threats
As of 2022, R. yavaricola is only known to occur in Rio Yavari, but may be more widely distributed. There is insufficient data of the species. Therefore, according to the IUCN Red List criteria, R. yavaricola is considered Data Deficient (DD) (Perez-Peña et al. 2010, IUCN 2020).

Relation to Humans
The Ranitomeya genus is found in the pet trade due to its vibrant aposematic coloration. In captivity, they are fed insects not found in their natural habitat; this removes their poisonous attribute (Perez-Peña et al. 2010).

As of 2022, dendrobatid frog collectors are seeking to buy R. yavaricola due to its beautiful colorations. Fortunately, they have no success in acquiring them since R. yavaricola is not heavily studied yet and is hard to catch. There are no known pet owners with R. yavaricola, but they are highly desirable and may appear in the market soon (IUCN 2020).

Possible reasons for amphibian decline

General habitat alteration and loss
Predators (natural or introduced)
Intentional mortality (over-harvesting, pet trade or collecting)

Comments

PHYLOGENETIC RELATIONSHIPS:

Maximum Likelihood estimation of a 2124 base pairs sequence of mitochondrial DNA concluded that R. yavaricola is a sister species to R. cyanovittata. The next most closely related clade is composed of R. flavovittata, R. imitator, and R. vanzolinii (Perez-Peña et al. 2010). This was supported by Bayesian analyses on 12S, 16S, and cytB mtDNA (Brown et al. 2011).

When R. yavaricola was first collected by science in 2003, it was originally thought to be a morph of R. flavovittata due to similar dorsal patterns. However, R. yavaricola has distinct morphology and genetics (Perez-Peña et al. 2010).

ETYMOLOGY:

The species epithet, “yavaricola” means “inhabitant of the Yavari” using the combination of the reference to the Rio Yavari, the river that the frog inhabits, with the Latin suffix “-icola,” meaning, “inhabitant” (Perez-Peña et al. 2010).

References

Brown J.L., Twomey E., Amézquita A., De Souza M.B., Caldwell J.P., Lötters S., Von May R., Melo-Sampaio P.R., Mejía-Vargas D., Perez-Peña P., Pepper M., Poelman E.H., Sanchez-Rodriguez M., and Summers K. (2011). "A taxonomic revision of the Neotropical poison frog genus Ranitomeya (Amphibia: Dendrobatidae)." Zootaxa, 3083, 1-120. [link]

IUCN SSC Amphibian Specialist Group (2020). “Ranitomeya yavaricola (amended version of 2018 assessment)." The IUCN Red List of Threatened Species 2020: e.T78584863A177124873. Accessed in February 2022.

Perez-Peña, P.E., Chávez, G., Twomey, E., Brown, J. (2010) “Two new species of Ranitomeya (Anura: Dendrobatidae) from Eastern Amazonian Peru.” Zootaxa, 2439, 1-23 [link]

Species Account Citation: AmphibiaWeb 2022 Ranitomeya yavaricola <https://amphibiaweb.org/species/7487> University of California, Berkeley, CA, USA. Accessed Oct 11, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 11 Oct 2024.

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