Species Fact Profile: African Clawed Frog (Xenopus laevis)

                                                      African Clawed Frog

                                            Xenopus laevis (Daudin, 1802)

Range: Sub-Saharan Africa

Habitat:  Still Freshwater - Ponds, Bogs, Slow-Moving Streams

Diet:  Aquatic Insects and their Larvae, Crustaceans, Worms, Snails, Small Fish, Tadpoles

Social Grouping: Asocial

Reproduction: Mate year round, but especially in spring and summer (can mate several times per year).  Male clasps female from behind, then female lays up to 2000 eggs, which are externally fertilized.  Eggs stick to underwater substrates, hatch about one week later.  Metamorphosis complete in 6-8 weeks.  Sexually mature at 10-12 months

Lifespan: 30Years

      Conservation Status:  IUCN Least Concern

• Males 5-6 centimeters long, weigh 60 grams, females 10-12 centimeters long, weigh 200 grams.  Flattened body with small, wedge-shaped head.  Eyes and nostrils positioned on the top of the head.  Front limbs are smaller than hind limbs, with non-webbed fingers.  Hind legs are larger and webbed with powerful claws.  Lack eyelids and external ears
• Mottled green-gray-brown color (sometimes with brown or yellow spotting), paler on the underside.  Limited ability to change skin color in response to environment
• Lateral line (similar to fish) sensitive to vibrations in the water.  Visible as series of white markings running down both sides of the frog
• Almost totally aquatic, only leaves water when forced to migrate.  Clumsy and awkward on land, crawls rather than hops (have been observed more than 2 kilometers away from water).  If ponds dry up, they can burrow into the mud and lay dormant for up to a year
• Popular laboratory animal.  Historically were used as pregnancy indicators for humans; a female frog injected with a woman's urine would start to lay eggs if the woman was pregnant.  First vertebrate cloned in a lab, in 1962
• Invasive species across much of the world, having been introduced to the United States, South America, western Europe, and Indonesia, among other regions.  Believed to be the carrier of the chytrid fungus, which has since been spread around the world and imperiled other amphibian species (the clawed frog itself is immune to the fungus)