Bullock’s false toad is a rare and elusive species, usually found under logs in temperate beech woodland. It breeds in fast-flowing water, where its tadpoles develop by scraping algae from rocks. Bullock’s false toad has been found hiding under logs. The stomach contents of the first individual described by scientists were examined and found to comprise the remains of cockroaches, other insects and spiders, as well as a considerable mass of plant material. This species has only been sighted once since 1992 and, despite occurring in the Parque Nacional Nahuelbuta, is threatened by wood extraction and the establishment of pine plantations, which causes the siltation of its streams.
Evolutionary Distinctiveness
Order: Anura
Family: Calyptocephalellidae
The Calyptocephalellidae family is a recently defined group of amphibians. Its four members, comprising three false toads (genus Telmatobufo) and the helmeted water toad (genus Caudiverbera) are all found in Chile, and were formerly included in the much lager Leprodactylidae family (commonly known as the “Leptodactylid frogs”). As a group, the Leptodactylidae has been reorganised recently and split into a number of different families, including the Calyptocephalellidae. It is now thought that the redefined Leptodactylidae diverged from all other amphibian groups about 60 million years ago, five milllion years after the extinction of the dinosaurs. However, it seems the Calyptocephalellidae diverged around 70 million years before the Leptodactylid frogs – 130 million years before the present day. They started to evolve separately from all other modern amphibians 30 million years prior to the extinct common ancestor that gave rise to the elephant and the mouse, when dinosaurs were still in abundance! The false toads are a tiny and little-known genus, all members of which are endangered (Telmatobufo bullocki is Critically Endangered, Telmatobufo venustusis is Endangered, and Telmatobufo australis is Vulnerable). Their closest relative, the Vulnerable helmeted water toad, is a giant among amphibians, with females reaching lengths of over 300 mm. It feeds predominantly on other frogs and toads, although it is also capable of consuming small birds and mammals. Its huge tadpoles can grow to lengths of 15 cm and take about two years to metamorphose. The Calyptocephalellidae family is therefore a highly evolutionarily distinct, unusual and endangered group of amphibians.
Description
Bullock’s false toad is a toad-like frog, with a stocky body, long slender legs, and webbed toes. Adults have a total body length of 60-80 mm. The fingers are not webbed and the tips of all digits are pointed and not dilated into discs. The skin along the back is covered in raised, rounded glands and prominent parotoid glands are present either side of the head just behind the eyes, appearing as large, oval lumps. The ventral skin is smooth. This species is mottled greyish-brown in colour, with darker spots corresponding to the round, elevated glands along the back.
Ecology
Very little is known about this species. Since its formal discovery in 1952, it has been seen very infrequently, and there are records of just one sighting since 1992. Adults may be found hiding under logs in temperate beech forest, and it is known to breed in fast-flowing streams. The tadpoles are free-swimming and feed by scraping algae from submerged rocks. Bullock’s false toad has been found hiding under logs. The stomach contents of the first individual described by scientists were examined and found to comprise the remains of cockroaches, other insects and spiders, as well as a considerable mass of plant material. This diet indicates that Bullock’s false toad has terrestrial (or ground-dwelling) feeding habits.
Order: Anura
Family: Calyptocephalellidae
The Calyptocephalellidae family is a recently defined group of amphibians. Its four members, comprising three false toads (genus Telmatobufo) and the helmeted water toad (genus Caudiverbera) are all found in Chile, and were formerly included in the much lager Leprodactylidae family (commonly known as the “Leptodactylid frogs”). As a group, the Leptodactylidae has been reorganised recently and split into a number of different families, including the Calyptocephalellidae. It is now thought that the redefined Leptodactylidae diverged from all other amphibian groups about 60 million years ago, five milllion years after the extinction of the dinosaurs. However, it seems the Calyptocephalellidae diverged around 70 million years before the Leptodactylid frogs – 130 million years before the present day. They started to evolve separately from all other modern amphibians 30 million years prior to the extinct common ancestor that gave rise to the elephant and the mouse, when dinosaurs were still in abundance! The false toads are a tiny and little-known genus, all members of which are endangered (Telmatobufo bullocki is Critically Endangered, Telmatobufo venustusis is Endangered, and Telmatobufo australis is Vulnerable). Their closest relative, the Vulnerable helmeted water toad, is a giant among amphibians, with females reaching lengths of over 300 mm. It feeds predominantly on other frogs and toads, although it is also capable of consuming small birds and mammals. Its huge tadpoles can grow to lengths of 15 cm and take about two years to metamorphose. The Calyptocephalellidae family is therefore a highly evolutionarily distinct, unusual and endangered group of amphibians.
Description
Bullock’s false toad is a toad-like frog, with a stocky body, long slender legs, and webbed toes. Adults have a total body length of 60-80 mm. The fingers are not webbed and the tips of all digits are pointed and not dilated into discs. The skin along the back is covered in raised, rounded glands and prominent parotoid glands are present either side of the head just behind the eyes, appearing as large, oval lumps. The ventral skin is smooth. This species is mottled greyish-brown in colour, with darker spots corresponding to the round, elevated glands along the back.
Ecology
Very little is known about this species. Since its formal discovery in 1952, it has been seen very infrequently, and there are records of just one sighting since 1992. Adults may be found hiding under logs in temperate beech forest, and it is known to breed in fast-flowing streams. The tadpoles are free-swimming and feed by scraping algae from submerged rocks. Bullock’s false toad has been found hiding under logs. The stomach contents of the first individual described by scientists were examined and found to comprise the remains of cockroaches, other insects and spiders, as well as a considerable mass of plant material. This diet indicates that Bullock’s false toad has terrestrial (or ground-dwelling) feeding habits.
Habitat
The habitat of Bullock’s false toad is fast-flowing streams that flow through temperate Nothofagus (southern beech) forest. It can be found hiding under logs and it thought to be tolerant of moderate habitat destruction.
Distribution
This species is known from only a few locations in the Coastal Range, Nahuelbuta in the Arauco Province of Chile, between 37° and 38°S. It has an altitudinal range of 800-1,200 metres above sea level.
Population Estimate
Bullock’s false toad is extremely rare. Extensive fieldwork by several herpetologists within the range of this species between 1992 and 2002 has turned up only a single adult (in 2002).
Population Trend
This species is thought to be in decline by the IUCN Red List of Threatened Species.
Status
Bullock’s false toad is listed as Critically Endangered in the IUCN Red List of Threatened Species, because its area of occupancy is probably less than 500 km sq., with all individuals in fewer than five locations, and there is a continuing decline in the extent and quality of its habitat in Arauco Province, Chile.
Threats
The major threat to the species is wood extraction from its temperate beech forest habitat and the establishment of pine plantations, which causes siltation of streams, making it difficult for the tadpoles to feed.
Conservation Underway
Bullock’s false toad occurs in the Parque Nacional Nahuelbuta, although there are no specific conservation measure ongoing for this species, and additional protection and maintenance of existing habitat is still urgently required.
The habitat of Bullock’s false toad is fast-flowing streams that flow through temperate Nothofagus (southern beech) forest. It can be found hiding under logs and it thought to be tolerant of moderate habitat destruction.
Distribution
This species is known from only a few locations in the Coastal Range, Nahuelbuta in the Arauco Province of Chile, between 37° and 38°S. It has an altitudinal range of 800-1,200 metres above sea level.
Population Estimate
Bullock’s false toad is extremely rare. Extensive fieldwork by several herpetologists within the range of this species between 1992 and 2002 has turned up only a single adult (in 2002).
Population Trend
This species is thought to be in decline by the IUCN Red List of Threatened Species.
Status
Bullock’s false toad is listed as Critically Endangered in the IUCN Red List of Threatened Species, because its area of occupancy is probably less than 500 km sq., with all individuals in fewer than five locations, and there is a continuing decline in the extent and quality of its habitat in Arauco Province, Chile.
Threats
The major threat to the species is wood extraction from its temperate beech forest habitat and the establishment of pine plantations, which causes siltation of streams, making it difficult for the tadpoles to feed.
Conservation Underway
Bullock’s false toad occurs in the Parque Nacional Nahuelbuta, although there are no specific conservation measure ongoing for this species, and additional protection and maintenance of existing habitat is still urgently required.
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