Description
This frog is moderate-sized with a robust body, a snout-vent length of 70.8 mm, and long, slender limbs. This species has only been described from one adult specimen. The head length is one-third of the snout-vent length. The snout is shortened, and the nostrils are closer to the snout tip than to the eye. This frog lacks a tympanum, but has large, oval paratoid glands. The back has many prominent oval and round glands, while the underside is smooth. The forelimbs are thin with folds of skin on the upper arm, elongated glands extending from the elbow to the hand, and free fingers. There is a noticeable inner palmar tubercle. Relative finger lengths are as follows: 3 > 4 > 2 > 1. The hind limbs are also thin, with a tarsal fold present and webbing on the toes extending to the toe tips. The inner metatarsal tubercle is flat and faint, whereas the outer metartarsal tubercle is absent. The subarticular tubercles are faint. Relative toe lengths are as follows: 4 > 5 = 3 > 2 > 1 (Formas and Veloso 1982).

This frog has a unique orange-spotted coloration in life that easily distinguishes it from any other frog species. In preservative, other Telmatobufo species have a few coloration differences that distinguish it from T. venustus. The back is brown in T. bullocki and gray in T. australis. The underside is light gray in T. australis with uneven dark spots, and the underside is spotted brown in T. bullocki. The outer edge of the fifth toe in T. venustus is wider in length than in T. bullocki, and lacks glands in that area. The toe tips are rounded in T. venustus versus pointed in T. bullocki and T. australis (Formas and Veloso 1982).

In life, it is black with orange spotting on the head, back, paratoids, and limbs. There are two orange stripes behind the paratoids that run down both sides of the midline of the body. There is some yellow spotting on the sides of the body, as well as the backside of the lower thighs, the backside of the feet, and the inner forearm. The fingertips and toe tips are yellowish-orange. In preservative, adult specimens are white, and juvenile specimens are black with uneven white spots (Formas and Veloso 1982).

Besides the aforementioned color differences between the adult and juvenile specimens in preservative, no other information is available on variation within the species (Formas and Veloso 1982).

See below for description of the Larva.

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Chile

View distribution map in BerkeleyMapper.

Telmatobufo venustus is distributed narrowly on the western slope of the Chilean Andes between the latitudes of 28.5° - 38.5°S and between the elevations of 1500 - 1700 m above sea level. It occurs in temperate Nothofagus (southern beech) forests along fast streams with large boulders. It is a secretive frog that is rarely encountered, and recently has only been found in Parque Nacional Altos de Lircay (Formas and Veloso 1982, Fenolio et al. 2011).

Life History, Abundance, Activity, and Special Behaviors
This frog is rare. It is nocturnal and has been found at night sitting on large boulders in the splash zone of mountain streams. It has also been found under Nothofagus logs. It swims via asynchronous movement of the limbs, and its nostrils remain above the water at all times. The stomach contents from one adult specimen included snails, beetles, flies, and plant material. Introduced trout are believed to prey on larvae. It lays creamy white eggs (Formas and Veloso 1982).

Larva
The larvae have a sinistral spiracle facing backwards and slightly up. When viewed from the side, the body is elliptical-shaped. The snout tip is truncate, whereas the tail tip is smoothed out. The mouth is located on the underside and is about 2/3 of the maximum body width. There are two large elliptical glands behind the eyes, as well as several smaller round glands going down the back (Diaz et al. 1983).

In life, the larvae are dark with orange spots on the head and back. In formalin, the coloration fades to dark brown (Diaz et al. 1983).

The larvae are adapted to fast-flowing mountain streams and possess a large oral disk to help them attach onto surfaces (Diaz et al. 1983, Fenolio et al. 2011, Formas and Veloso 1982).

Trends and Threats
The population of T. venustus is thought to be declining due to a combination of habitat loss, habitat alteration, and introduced predators. The Nothofagus forests in which it lives are being converted into eucalyptus and pine forests. Larvae are nonexistent or exist in low numbers in streams with introduced rainbow trout. The streams where it occurs are flooded due to dam construction. The species has been swabbed and tested for chytrid, with the swabs coming back negative. However, researchers were hesitant to conclude that chytrid was absent from the area due to the low sample size of frogs swabbed (Fenolio et al. 2011).

Possible reasons for amphibian decline

General habitat alteration and loss
Habitat modification from deforestation, or logging related activities
Mining
Dams changing river flow and/or covering habitat
Habitat fragmentation
Predators (natural or introduced)

Comments
The species authority is: Philippi, R. A. (1899). Descripciones breves de dos nuevas especies de sapos (Bufo). Anales Universidad de Chile 104:723-725.

This species was originally ascribed to the genus Bufo in 1899 by Philippi. In 1972, it was placed in the genus Aruncus by Donoso-Barros. Lynch placed this species in the genus Telmatobufo in 1978. Formas and Veloso wrote a detailed taxonomical description of this species in 1982 and using osteological analysis, confirmed its placement in the Telmatobufo genus (Formas and Veloso 1982).

The first description of the larvae was in 1983, which was 84 years after the original species description (Fenolio et al. 2011).

References

Diaz, N., Sallaberry, M., Nuñez, H. (1983). ''The Tadpole of Telmatobufo venustus (Anura: Leptodactylidae) With a Consideration of Generic Relationships.'' Herpetologica, 39(2), 111-113.

Fenolio, D. B., Charrier, A., Levy, M. G., Fabry, M. O., Tirado, M. S., Crump, M. L., Lamar, W. W., Calderón, P. (2011). ''A Review of the Chile Mountains False Toad, Telmatobufo venustus (Amphibia: Anura: Calyptocephalellidae), with Comments on its Conservation Status.'' Herpetological Review, 42(4), 514-519.

Formas, J. R., Veloso, A. (1982). ''Taxonomy of Bufo venustus Philippi, 1899 (Anura: Leptodactylidae) from Central Chile.'' Proceedings of the Biological Society of Washington, 95(4), 688-693.

Species Account Citation: AmphibiaWeb 2023 Telmatobufo venustus: Chile Mountains False Toad <https://amphibiaweb.org/species/2731> University of California, Berkeley, CA, USA. Accessed Apr 19, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 19 Apr 2024.

AmphibiaWeb's policy on data use.