No special legal status has been given to Pyxicephalus species. Switak (1997) notes that advancing civilization has driven it near extinction in certain parts of its range.
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: least concern
Development - Life Cycle: metamorphosis
Because these frogs are such resilient animals, they might potentially have negative effects on the surrounding ecosystem if introduced by humans beyond their natural range.
African bullfrogs are eaten by humans, and have been collected for the commercial pet trade.
Pyxicephalus adspersus is carnivorous and will consume nearly any animal that can be overpowered and can fit in their huge mouths. Cannibalism is a common occurrence beginning the moment they metamorphose. Many of their first meals will be a member of the same egg mass. Other prey items may include invertebrates, other species of frogs, reptiles, small mammals, and even small birds. The tongue is folded over inside the mouth. To capture a potential meal, it will drop its lower jaw with considerable force, causing the tongue to flip over and out of the animal's mouth, siezing the prey (Moore 1997, Switak 1997).
The range of Pyxicephalus adspersus is mostly sub-Saharan. Its range extends north and east into Somalia, west to Nigeria, and south to the Cape Provence, South Africa.
A closely related, slightly smaller species, Pyxicephalus edulis, occupies a smaller range in southern Africa, from Zimbabwe and northern South Africa to (probably) Botswana, Mozambique, and Zambia (Passmore and Carruthers, 1995; Channing et al., 1994).
Biogeographic Regions: ethiopian (Native )
One of the most adaptable amphibians on earth, Pyxicephalus can tolerate some of the harshest environments in Africa.
Certain areas of their range can be completely dry for years at a time, and can reach surface temperatures over 100 degrees F, and drop to below freezing during the winter. Protected in an underground estivation chamber, the frogs wait it out until more suitable conditions occur. When the rainy season begins, they occupy temporary floodplains and rapidly drying puddles scattered around the African countryside.
Pyxicephalus have been known to inhabit extremely hostile regions from the Kalihari desert, to the high veld domains between 4000 and 5000 feet above sea level (Switak 1997).
Terrestrial Biomes: desert or dune ; savanna or grassland
Aquatic Biomes: lakes and ponds
Average lifespan
Status: captivity: 16.2 years.
Male Pyxicephalus adspersus can reach lengths of more than 9 inches and weigh over 2 pounds. Females are much smaller. Males are olive in color, with yellow to orange on the throat region. Females are olive to light brown with cream to white throat areas. Both sexes have ridges running laterally on the dorsal surface. Juveniles are much more colorful than adults. Several white to yellow lines run down the animal's dorsal area on an overall mottled background. Both these dorsal lines, and mottling disappear with age. Adults have a spade like metatarsal tubercle on each hind foot to aid in digging. The front toes are thick and blunt with no webbing, the rear toes are slightly webbed. These frogs have massive skeletons with extremely large, heavy skulls. The bottom jaw has three odontodes which act as huge teeth, and are used in restraining struggling prey (Moore 1997, Switak 1997).
Other Physical Features: ectothermic ; bilateral symmetry
During the breeding season, males will congregate in large groups. Much aggression occurs in these groups with larger males pushing, pursuing, biting, even consuming smaller males. The large males will push their way to the center of the group, establish and defend a small area and begin calling. The call lasts about a second and can be described as a deep low-pitched whoop. The females will hear this call and swim underwater to the center of the group, to avoid the smaller males and surface in the defended area of a larger male. As they surface, they are persuaded until finally being seized by a male. Amplexus occurs in shallow water to allow the pair to stand on the bottom. Eggs are fertilized above the water's surface. As many as 4000 eggs may be released. The males exhibit parental care. Males will watch over and defend the eggs which hatch in two days. After hatching, the tadpoles will feed on each other, as well as on small fish and invertebrates. Defending males will continue to watch over the tadpoles which will metamorphose within three weeks. Moore states that during times when the pool nears dessication, the male will dig a channel between his offspring and the larger body of water. This parental care comes with a price, however, as the male will consume many of the tadpoles while he is defending them (Moore 1997; Channing et al., 1994).
Key Reproductive Features: gonochoric/gonochoristic/dioecious (sexes separate)
The African bullfrog (Pyxicephalus adspersus), also known as the Giant bullfrog or the South African Burrowing Frog, is a species of frog in the family Pyxicephalidae. It is also known as the pixie frog due to its scientific name. It is found in Angola, Botswana, Kenya, Malawi, Mozambique, Namibia, South Africa, Tanzania, Uganda, Zambia, Zimbabwe, and possibly the Democratic Republic of the Congo. It has been extirpated from Eswatini.[1] It has long been confused with the edible bullfrog (P. edulis), and species boundaries between them, including exact range limits, are not fully understood.[1][2] Additionally, P. angusticeps of coastal East Africa only was revalidated as a separate species in 2013.[2]
The natural habitat of the African bullfrog is moist to dry savanna, subtropical to tropical dry shrubland, intermittent freshwater lakes, intermittent freshwater marshes, arable land, pastureland, canals, and flooded ditches. It is among the largest anurans on the planet, sixth only to the goliath frog, the helmeted water toad, the Lake Junin frog, the Blyth's river frog, and the cane toad.[3] The males weigh up to 1.4 kg (3.1 lb) and grow to 24.5 cm (9.6 in) in snout–to–vent length. Females are half the size of males, which is unusual, considering that most female amphibians are (generally) larger than males, to help the amplexus.[4][5][6][7]
The African bullfrog is a voracious carnivore, eating insects, other invertebrates, small rodents, reptiles, small birds, fish, and other amphibians that can fit in their mouths.[5][8][9] It is also a cannibalistic species—the male African bullfrog is known for occasionally eating the tadpoles he guards.[10] An African bullfrog kept at the Pretoria Zoo in South Africa once ate 17 juvenile Rinkhals snakes (Hemachatus haemachatus).[11] They emit a loud croaking and a bleating sound when stressed or handled. It is one of the three frog species regularly kept in captivity that have sharp teeth and willingly bite humans when provoked or handled; the other two are Pacman frogs and Budgett's frogs.[12]
Breeding typically starts after about 65 mm (2.6 in) of rain over the course of two days. They breed in shallow, temporary water bodies, such as pools, pans, and ditches. Eggs are laid in the shallow edge of the pond, but fertilization takes place above water.[13]
The African bullfrog males call out during the rainy season. The call lasts about a second and can be described as a low-pitched whoop.[14] Males have two breeding strategies, depending on their age. Young males congregate in a small area, perhaps only 1–2 m2 (11–22 sq ft) of shallow water. The larger males occupy the centre of these breeding arenas or leks, and attempt to chase off other males. Often, they fight, causing injury or even killing one another. The dominant male attempts to prevent other males from breeding. A female approaches the group of males by swimming along at the surface until she is within a few metres of the group. Then, the female dives to avoid the smaller males and surfaces in the defended area of a larger male in the middle of the group. This helps to ensure that she mates with the dominant male.[13]
The female lays about 3,000 to 4,000 eggs at a time. The tadpoles hatch, and after two days, start feeding on vegetation, small fish, invertebrates, and even each other. Defending males continue to watch over the tadpoles, which metamorphose within three weeks. During the tadpole's development, the father guards his young. Due to the male bullfrog's overprotective behaviour, he pounces and bites anything that he views as a threat. If the pool is in danger of drying out, the father uses his legs and head to dig a canal from the drying pond to a bigger pond. He continues to guard the tadpoles until they are old enough to fend for themselves, although he may also eat some of them.[13][15]
The African bullfrog is an exotic pet in many countries around the world. Animals sold are generally bred in captivity. Pet African bullfrogs may live for 35 years in captivity.[5]
{{cite journal}}: CS1 maint: multiple names: authors list (link) The African bullfrog (Pyxicephalus adspersus), also known as the Giant bullfrog or the South African Burrowing Frog, is a species of frog in the family Pyxicephalidae. It is also known as the pixie frog due to its scientific name. It is found in Angola, Botswana, Kenya, Malawi, Mozambique, Namibia, South Africa, Tanzania, Uganda, Zambia, Zimbabwe, and possibly the Democratic Republic of the Congo. It has been extirpated from Eswatini. It has long been confused with the edible bullfrog (P. edulis), and species boundaries between them, including exact range limits, are not fully understood. Additionally, P. angusticeps of coastal East Africa only was revalidated as a separate species in 2013.
The natural habitat of the African bullfrog is moist to dry savanna, subtropical to tropical dry shrubland, intermittent freshwater lakes, intermittent freshwater marshes, arable land, pastureland, canals, and flooded ditches. It is among the largest anurans on the planet, sixth only to the goliath frog, the helmeted water toad, the Lake Junin frog, the Blyth's river frog, and the cane toad. The males weigh up to 1.4 kg (3.1 lb) and grow to 24.5 cm (9.6 in) in snout–to–vent length. Females are half the size of males, which is unusual, considering that most female amphibians are (generally) larger than males, to help the amplexus.
