What
was historically included in Xenopus laevis is now several species. All
members of the genus Xenopus are ecologically similar. They are non-selective
predators that eat anything in the aquatic environment: invertebrates,
crustaceans, amphibians, and fish. They have a long life span, an extended
breeding season,
and are prolific reproducers. They are capable of surviving through severe
drought and freezing conditions.
This
species was widely used in the 1940's
and 1950's for human pregnancy testing. Populations of African clawed frogs
(Xenopus laevis) have been introduced into several
areas in North America and other countries. Not a great deal is known about
its impacts on native species. However, these voracious frogs are very
prolific and have proven capable of colonizing a broad range of aquatic habitats.
They have become established in at least seven counties in Southern California,
and there is some evidence it poses a threat to native amphibians and fishes
there. They grow to be about the size of an adult human fist.
The dwarf
African clawed frogs, the genus Hymenochirus, are widely sold in the pet
trade and are unlikely to present a threat where they to escape due Washington's
climate regime. They are smaller, seldom exceeding an inch and a half, andtheir
eyes are not as prominent as the larger species. They also have webbing on
their front feet, and appear thinner around the waist.
