Andersson, L. G. 1945. Batrachians from East Ecuador, collected 1937, 1938 by Wm. Clarke-Macintyre and Rolf Blomberg. Arkiv för Zoologi. Stockholm 37A(2): 1–88.

	hear Fonozoo call

Description

Dendropsophus bifurcus is a slender frog that has a total length of 28 mm in males and 35 mm in females. The head is more broad than long and it is also more broad than the body with the widest section at the eyes. The snout is broadly rounded when viewed dorsally and it is truncated in profile. The nostrils are close to the tip of the snout and the eyes are protruding. The interorbital space is much broader than the upper eyelid. The canthus rostralis is slightly marked and the loreal region is vertical, not concave. The tympanum is distinct, round, and nearly half the diameter of the eye, and the fold above the tympanum is not very distinct. The chin is smooth. The dorsal skin is smooth and the ventral skin is granular. There is an extensive axillary membrane that extends nearly to the elbows. The fingers are slender; the outer fingers are ⅓ webbed, and the inner fingers have no webbing. The disks are large but are not larger than the tympanum. The hind limbs are long and the length from the tibia reaches nearly the tip of the snout. The toes are ⅔ webbed. The webbing on the 1st, 5th, and outer sides of the 2nd and 3rd toes reaches about to the disks, and the web on the 4th and inner sides of the 2nd and 3rd reaches the base of the penultimate phalanx and it extends as narrow borders to the disks. The disks are well developed, but are smaller than the disks on the fingers (Andersson 1945; Duellman 1978).

Dendropsophus bifurcus is most similar to D. leucophyllatus, but D. bifurcus has a smaller size and has one light fleck on the heels, where D. leucophyllatus has two light flecks. These traits also differentiate it from most other Dendropsophus species. It differs from D. salli by its white spots on the dorsum, its distinct advertisement call, and the traits mentioned previously (Jungfer et al. 2010).

In preservative, the main dorsal color is a chocolate brown with barely visible white points and the forehead has a white triangular shape that starts at the nose and goes to the inner corners of the eyes. This white area continues down the sides of the dorsum of D. bifurcus in two distinct stripes that start at the inner corners of the eyes and end at the sacrum. In some individuals, the dorsolateral lines connect at a white spot on the rump. There are two other white spots: one above the vent and another on the heel. The ventral surface is a brownish white (Andersson 1945).

In life, at night, the hands, feet, axillar, and ventral surfaces of the limbs are orange, and the dorsum is pale brown with some individuals having minute black flecks. The spots and lines that were white in preservative are a yellowish tan in life, and the vocal sac is yellow. The ventral side of the limbs and the webbing are orange at night. The iris is a grayish bronze (Duellman 1978).

There is sexual size dimorphism with the females being larger. The rump spot varies among individuals of being discrete, connected to one of the dorsolateral lines, or connected to both of the dorsolateral lines (Duellman 1978).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Bolivia, Brazil, Colombia, Ecuador, Peru

View distribution map in BerkeleyMapper.

Dendropsophus bifurcus is found in the Upper Amazon Basin of Ecuador and Peru. It is unclear whether the Dendropsophus frogs in Bolivia are solely D. salli or are D. salli and D. bifurcus living in sympatry (Jungfer et al. 2010). Most individuals have been observed in secondary forest and forest-edge habitats, and they are found in humid transition lowland forests (Duellman 1978; De la Riva et al. 2000).

Life History, Abundance, Activity, and Special Behaviors

Dendropsophus bifurcus has two call types. The more common call is emitted by single males and consists of one to two notes. The first note is longer (147 ms), consists of 14 - 18 evenly spaced pulses, and is occasionally followed by one to three additional shorter notes. The second call type is done in a chorus and differs from the first call type by having two to three notes added at the end of the call. These notes are alternated between a couple of individuals rapidly in what is called, “duetting”. The males for both call types tended to call from floating or aquatic plants or short emergent vegetation 0 - 18 cm above the water (Marquez et al. 1993).

Dendropsophus bifurcus is an opportunistic breeder. The males call all throughout the rainy season (November through April) and gravid females have been found in all months except June and December through February (Marquez et al. 1993; Duellman 1978). The clutch size varies from about 150 - 250 eggs and they are deposited on the upper surfaces of the leaves of emergent plants close to water (Duellman 1978).

Their most common prey are small arthropods such as flies, spiders, and beetles. They have also been observed preying on moths (Duellman 1978).

Larva

In Gosner stage 32, the tadpoles have a body length of 9.5 mm and a total length of 31.0 mm. The body is violin shaped with a truncate snout dorsally and ovoid with a rounded snout laterally. The eyes are situated laterally and are large. The nostrils are halfway between the tip of the snout and the eyes. The opening of the sinistral spiracles is at about the midlength of the body and it is directed posterodorsally. The dorsal fin does not extend onto the body and the tail is approximately 70 percent of the depth of the dorsal fin and ends in a long filament. The mouth lacks lateral folds and is anterior. The mouth is surrounded by one row of large, blunt labial papillae except at the middle of the upper lip. The beaks are finely serrated and moderately robust, and the denticles are absent (Gosner 1960; Duellman 1978).

The dorsum is tan with broad, black lateral stripes that have a metallic cream stripe bordering below it. The ventral surface is silvery white with three longitudinal black stripes. The distal portion of the dorsal fin and the caudal musculature are black, and there is a cream stripe on the proximal section of the caudal musculature. The tip of the tail and fins are cream, and the dorsal fin has black flecks. The iris is a reddish bronze (Gosner 1960; Duellman 1978).

The tadpoles have been found in shallow, densely vegetated, temporary pools and ditches, where they take refuge in the vegetation. Individual tadpoles have been observed near the surface of the open water but will retreat to the vegetation when disturbed (Gosner 1960; Duellman 1978).

Trends and Threats

This species range is very widespread and is not under any direct threats. There has been some localized habitat loss due to clear cutting (IUCN 2017).

Possible reasons for amphibian decline

Habitat modification from deforestation, or logging related activities

Comments

Parsimony methods in a total evidence analysis of the Dendropsophus genus using previously published data as well as new samples of 12S and 16S mtDNA and nucDNA, placed D. bifurcus as sister to D. manonegro, and the two combined are sister to (Orrico et al. 2021).

References

Andersson, L.G. (1945). Batrachians from East Ecuador. Arkiv för Zoologi, 37A(2).

De la Riva, I., Köhler, J., Lötters, S., and Reichle, S. (2000). Ten years of research on Bolivian amphibians: updated checklist, distribution, taxonomic problems, literature and iconography. Rev. Esp. Herp., 14,19 - 164. [link]

Duellman, William E. The biology of an equatorial herpetofauna in Amazonian Ecuador. Lawrence, Kansas: The University of Kansas, 1978.

IUCN SSC Amphibian Specialist Group. (2023). Dendropsophus bifurcus. The IUCN Red List of Threatened Species 2023: e.T78903749A3029438. https://dx.doi.org/10.2305/IUCN.UK.2023-1.RLTS.T78903749A3029438.en. Accessed on 06 February 2024.

Gosner, K.L. (1960). A simplified table for staging anuran embryos and larvae with notes on identification. Herpetologica, 16(3), 183-190. [link]

Jungfer, K., Reichle, S., and Piskurek, O. (2010). Description of a new cryptic southwestern Amazonian species of leaf-gluing treefrog, genus Dendropsophus (Amphibia: Anura: Hylidae). Salamandra, 46(4), 204-213. [link]

Márquez, R., De la Riva, I., and Bosch, J. (1993). Advertisement calls of Bolivian species of Hyla (Amphibia, Anura, Hylidae). Biotropica, 25(4), 426 - 443. [link]

Orrico, V.G.D., Grant, T., Faivovich, J., Rivera-Correa, M., Rada, M.A., Lyra, M.L., Cassini, C.S., Valdujo, P.H., Schargel, W.E., Machado, D.J., Wheeler, W.C., Barrio-Amorós, C., Loebmann, D., Moravec, J., Zina, J., Solé, M., Sturaro, M.J., Peloso, P.L.V., Suarez, P. and Haddad, C.F.B. (2021). The phylogeny of Dendropsophini (Anura: Hylidae: Hylinae). Cladistics, 37: 73-105. [link]

Species Account Citation: AmphibiaWeb 2024 Dendropsophus bifurcus: Upper Amazon Treefrog <https://amphibiaweb.org/species/734> University of California, Berkeley, CA, USA. Accessed Nov 22, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 22 Nov 2024.

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