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Clawed Frog Xenopus laevis Description The clawed frog is about 4 inches long, with large females reaching up to 5 inches. The front legs are short and weak, each having 4 long, straight fingers. The back legs, however, are long and very muscular, with large webs between the toes. The 3 inner toes on each back foot have sharp black claws. Clawed frogs can change color to match their background. When this is a contrasting mixture of light and shade, the frogs are mottled, but they can become almost black or a pale buff if placed against uniformly dark or light areas. Distribution and Habitat Clawed frogs are native to southern Africa, but have been introduced into California, Chile, Great Britain, and other locations around the world. They live in warm, stagnant grassland ponds, as well as in streams in arid and semi-arid regions. They are almost totally aquatic, only leaving the water when forced to migrate. When the swamps and ponds dry up in summer, the frogs burrow into the mud to remain cool and moist. If the bed, too, dries out, however, the frogs will hop overland in search of permanent water. Although they spend their lives in water, clawed frogs still need to come to the surface to breathe. A large frog will surface about every 10 minutes, but can survive much longer if prevented from surfacing. Feeding Clawed frogs catch their prey with their hands, using their fingers to prevent escape. They feed on carrion, crustaceans, aquatic larvae and small fish. Mosquito eggs and larvae are eaten in vast numbers, so that where abundant, clawed frogs benefit men by reducing malaria and other mosquito-borne diseases. Small food particles are swept into the mouth by a fanning action of the front feet, while larger pieces of food are torn apart by the hind claws. Tadpoles are exclusively filter feeders. Reproduction Mating can take place during any time of the year, but is most common in the spring, and can take place up to four times per year. During the breeding season, the males croak morning and evening. Females answer this croaking with either an acceptance call (a rapping sound) or a rejection call (slow ticking sound). Mating usually takes place at night. The male fertilizes the eggs while the female lays them. Eggs are laid singly on the stems of water plants or on stones. Tadpoles hatch after about a week, depending on the water temperature. They spend about a week hanging motionless at the surface of the water, living off the remains of the egg yolk. It takes about 2 months for the tadpole to become an adult frog, and about 3 to 4 years to reach sexual maturity. Scientific Classification phylum Chordata SOURCE |
SKC Films Library >> Science >> Zoology >> Reptiles and
Amphibians >> Order Anura This page was last updated on June 14, 2017. |