Description
Diasporus pequeno is a small, slender-bodied eleutherodactylid frog has a male snout-vent length range between 16.9 – 19.9 mm and female range between 21.5 – 24.8 mm. The dorsal skin is smooth with scattered tubercles and a small supraciliary tubercle. The ventral skin is smooth, with no evident discoidal fold. The head is as wide as long and widest at the angles between the jaw. The snout is short and rounded in both the dorsal and profile view. The somewhat dorsolaterally directed nostrils are located at the tip of the snout and visible from the front and dorsal views but not visible from the ventral view. The canthus rostralis is round and the loreal region is slightly concave. The eye is 1.7 times the length of the snout. The tympanum is of moderate size and has a tympanic annulus with a visible lower half, but no tympanic membrane. The vocal sac is well developed, and vocal slits are present (Batista et al. 2016).

The moderately sized hands possess a round to oval palmar tubercle, a smaller, elongated thenar tubercle, and small, round accessory tubercles. There are no nuptial pads. The relative lengths of the unwebbed fingers are I < II < IV < III, with finger II only reaching the disc on finger IV and the disc on finger III being more than 2 times wider than the distal end of the phalanx it sits upon. The discs are even and broadened and the tips also possess expanded ungual flaps with the longest fingers being lanceolate. . The finger pads are globular in the profileThe fingers lack fringes and have round, globular subarticular tubercles, with the first tubercle being the most obvious. The supernumerary tubercles are rounded and small (Batista et al. 2016).

The hindlimbs are moderately long. The foot does not have a tarsal ridge but has an oval inner metatarsal tubercle that is larger than the rounded and slightly pointed outer metatarsal tubercle. The unwebbed, fringeless toes have a relative length of I < II < III < V < IV and end in even, broadened discs with expanded ungual flaps that are lanceolated on toes III and IV. Toe I only reaches up to the last third of the distal phalange of toe II. The expanded disc of toe IV is over 1.7 times larger then the phalanx below it. The toe pads are globular in the profile. There is one subarticular tubercle on toes I and II, two on toes III and V, and three subarticular tubercles on toe IV (Batista et al. 2016).

Diasporus pequeno can be differentiated from Diasporus tinker by the former having round digit pads and a bright yellow vocal sac in males. From Diasporus gularis, the focal species can be differentiated by having a brownish dorsum with dark blotches, translucent ventrum with dark speckles and sky-blue blotches, and a bright yellow vocal sac (Batista et al. 2016).

In life, the dorsal surface is walnut brown with sepia blotches and small sky-blue dots. The interorbital band is a flesh ocher with a sepia band border on the posteriorly end. The groin area is ruby red. The axilla and venter are also walnut brown but with a pale pink mottled pattern. The throat is suffused with a buff coloration. The toes and fingers have a pale buff band just before the disc cover. The iris is geranium with fine sepia reticulations. In preservative, the dorsum becomes a drab ground color and the dorsolateral lines become light orange yellow. The groin and ventral areas become light buff with small sepia points and the ungula flaps become cinnamon-drab (Batista et al. 2016).

The ungual flaps range from lanceolate to papiliate (Batista et al. 2016).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Panama

View distribution map in BerkeleyMapper.

Diasporus pequeno is found in the montane forests of the Darien mountain range in eastern Panama, at an elevations of 472 - 700 m a.s.l. Bromeliads, palms, vines, and small trees dominate the part of the montane rainforest that the species is found. Individuals have been found in open understories at 0.2 – 1.0 m above ground, in vegetation (Batista et al. 2016).

Life History, Abundance, Activity, and Special Behaviors
Diasporus pequeno lives close to the ground at about 0.2 – 1.0 meters above green leaves, between branches with dry leaves, or in bromeliads (Batista et al. 2016).

The advertisement call consists of single, short, monophasic notes lasting 0.09 – 0.15 s and reminiscent of a ‘tink’. At 24^oC, the interval between calls is 3.51 – 6.85 s and the call rate was 11.61 calls/minute. The low frequency range was 3.20 – 3.23 kHz, the high frequency range was 3.63 – 3.67 kHz. The fundamental and dominant frequency range was at 3.44 – 3.48 kHz (Batista et al. 2016).

Diasporus pequeno can be found in sympatry with D. diastema and D. quidditus, and all can be found actively calling together (Batista et al. 2016).

Trends and Threats
Little is known about the conservation risk of this species. Endemic to a small mountain range, the species could be vulnerable to both habitat loss and chytrid fungus (Batista et al. 2016).

Possible reasons for amphibian decline

General habitat alteration and loss
Disease

Comments
The species authority is: Batista, A., Kohler, G., Mebert, K., Andreas, H., Milan, V. (2016). “An integrative approach to reveal speciation and species richness in the genus Diasporus (Amphibia: Anura: Eleutherodactylidae) in eastern Panama.” Zoological Journal of the Linnean Society. 178, 267–311.

Frogs in the genus Diasporus were previously classified under the Eleutherodactylus diastema group (Hedges et al. 2008). Members of Diasporus are part of a cryptic complex of frogs, and there is the potential of there being more undescribed species (Hertz et. al. 2012).

Based on Bayesian Inference analysis of 16S, COI, and RAG1 genes, D. pesqueno is sister to the clade composed of members of the D. diastema complex, D. aff. quidditus, and D. tinker (Batista et al. 2016).

The species epithet, “pequeno”, is derived from the name of the last village at Río Tuquesa, Bajo Pequeño (or Bajo Chiquito), where this species was found (Batista et al. 2016).

References

Batista, A., Kohler, G., Mebert, K., Andreas, H., Milan, V. (2016). ''An integrative approach to reveal speciation and species richness in the genus Diasporus (Amphibia: Anura: Eleutherodactylidae) in eastern Panama.'' Zoological Journal of the Linnean Society, 178, 267-311.

Hedges, S. B., Duellman, W. E., Heinicke, M. P. (2008). ''New World direct-developing frogs (Anura: Terrarana): Molecular phylogeny, classification, biogeography, and conservation.'' Zootaxa, 1737, 1-182.

Hertz, A., Hauenschild, F., Lotzkat, S., Köhler, G. (2012). ''A new, golden frog species of the genus Diasporus (Amphibia, Eleutherodactylidae) from the Cordillera Central, western Panama.'' ZooKeys, 196, 23–46.

Species Account Citation: AmphibiaWeb 2018 Diasporus pequeno: Dink frog <https://amphibiaweb.org/species/8581> University of California, Berkeley, CA, USA. Accessed Apr 17, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 17 Apr 2024.

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