Chile False Toad

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).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).This species 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).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).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).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).

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).

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 thought to prey on larvae. It lays creamy white eggs (Formas and Veloso 1982). 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).

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).

Diagnosis A moderate size frog that is distinguished from its congeners in having dorsal and ventral areas black, the dorsum, head, and paratoid glands spotted with orange, and the outer border of the fifth toes broad and not glandular.

Known from the western slopes of the Chilean Andes from 35° 20'S to 38° 50'S (Altos de Vilches, Talca Province; Cordillera de Chillan, Chillan Province; Ralco, Bio Bio Province), at an elevation of 1,500-1,700m asl.

Adult morphology Body robust, limbs long and slender. Head depressed, slightly wider than long; head length 33.2% of snout-vent length; snout short, truncate (slightly concave in holotype). Lateral nostrils protruding; nostrils closer to the tip of snout than to eye. Eye length greater than distance between eye and nostril; internarial distance greater than interorbital distance. Tympanum absent; paratoid glands large, oval, greater than diameter of eye. Tongue rounded; prevomerine teeth in two separated fascicules between large choanae. Posterior limbs thin; tibiotarsal articulation reaching to anterior edge of paratoid gland. Toes webbed, interdigital membrane extending to tips of toes; length of toes in decreasing order IV, (V-III) II, I; inner metatarsal tubercle flat, indistinct; outer metatarsal tubercle absent; outer border of the fifth toe broad and not glandular; subarticular tubercles indistinct; tarsal fold present. Forelimbs thin; upper arm enveloped in folds of skin of body; fingers free, their lengths in decreasing order III-IV-II-I; inner palmar tubercle evident; elongated gland in ulnar position of forearm extending from elbow to hand. Skin of dorsum with numerous prominent, oval and round glands; skin of venter smooth. Color in preservative, whitish in holotype and black with irregular whitish spots in a juvenile. In life this animal had the venter, dorsum and extremities bright coal-black; head, paratoid glands, upper eyelids, elbow and tibiotarsal articulation areas orange spotted; two orange paravertebral stripes convergent below paratoid glands; minute yellow spots on flanks, dorsal and posterior thigh, dorsal surface of tarsus, and inner edge of forearm; tips of fingers and toes yellow. Measurements of the holotype (in mm): snout-vent length 70.8, head width 24.9, head length 23.5, thigh length 28.1, shank length 29.4, foot length 46.5, paratoid length 10.6, eye diameter 8.3, eyenostril distance 2.9, nostril-snout distance 5.3, internarial width 7.7, interorbital width 6.5. Larval morphology Body ovoid in lateral view 1.7 times longer than deep, 1.3 times longer than wide. Nostrils dorsal, small, closer to the eyes (4.9 mm) than to snout tip (10.7 mm), directed anterodorsolaterally; internarial separation larger (6.5 mm) than interorbital distance. Eyes small (4.0 mm diameter) directed laterodorsally, close to the dorsal midline (interorbital distance 2.6 mm). Spiracle sinistral, on the inferior half of the body, directed backward and slightly upwards, nearer to anal end (16.4 mm) than to the tip of the snout (22.5 mm). Anus dextral, covered with a skin fold with a pointed posterior end and joined to the tail base by a longitudinal skin fold. Tail deeper than body, 1.7 times body length. Caudal musculature stout, particularly at the tail base; muscular segmentation visible. Fins asymmetrical, dorsal larger than ventral, restricted to the last third of tail. Tail tip rounded. Snout tip blunt. Oral disk ventral slightly wider than two-thirds of the maximum body width, completely surrounded by small papillae. Two to three rows of papillae on upper lip and three to four on lower lip; no papillae on the commissures. Mandibles strong, crescent shaped, internal borders smooth. Tooth formula 2/3(1). Posterior limbs with tarsal fold, metatarsal and subarticular tubercles weak, internal border of the fifth toe thick; toes fully webbed; toe tips rounded. Color in formalin dark brown, venter slightly clearer; orange spots on the eyelids dorsum, dorsal surfaces of the femur and tibiae and on the external tarsal border of both hind limbs. A few yellow spots on the posterior surface of both thighs, on the internal border of both feet and toe tips. A lateral incision reveals an orange spot on the elbow of the right anterior limb. Minute chromatophores on caudal musculature and fins, regularly distributed. Behind the eyes (1 mm) two bright orange ovoid glandular protuberances almost double the size of eyes, separated by four times the interorbital distance. About fifty circular protuberances distributed on the rest of the body dorsum, most orange, smaller than those back of the eyes (diameter 1.8-3.1 mm); gular and ventral surfaces without glands. Tibiotarsal joints marked with medium sized, circular orange protuberances (diameter 4.8 mm). Other measurements of the larvae are: body length, 39.7 mm; tail length, 67.7 mm; maximum body width, 30.0 mm; maximum body height, 23.0 mm; and maximum tail height, 18.8 mm.

EN. Endangered,

Telmatobufo venustus is a species of frog in the family Calyptocephalellidae. It is endemic to Chile and occurs on the western slopes of the Andes in Maule and Bío Bío Regions. Its natural habitats are streams in temperate Nothofagus forests where it is found under rocks along the streams. The only stable population is in the Altos de Lircay National Reserve in Maule. The only other localities, both in the Bío Bío Region, are its type locality in Chillan, where it was not found in 2014, and Ralco where it was last observed in 1981. It is threatened by habitat loss caused by fires, conversion of native habitat to pine and eucalyptus plantations, and in Ralco, hydropower dams. Trout in Altos de Lircay are also a threat.