African clawed frogs aka Xenopus laevis. It is one of the 14 species in Genus Xenopus, and maybe the most popular. These frogs are native to sub-Saharan Africa. This frog in nature live in stagnant pools and a substrate of deep mud. They have lungs, which means they come to the surface for air. They have a lateral line system that looks like stitches along it's body that help it locate prey. These frogs have huge webbed feet, with 5 toes, and 3 claws on each foot. Males can grow to 2-4" svl (snout to vent length), and females growing 4-6"svl. The size for sexual maturity for these frogs is about 3"svl. Sexual maturity is between 10 months - 1 year. Males will 'call out' for a female. There is debate about whether females 'call back'. Well, i have heard 2 of my females calling back to one of my males. It is a soft clicking sound, different from the males.  It is interesting listening to them communicate to eachother. Telling the sex: Females have an extension at the vent site called a cloaca. This is where waste and eggs are released. I was able to see the cloaca in my females when they were about 2" svl.   Females get 'dirty hands', which means that the coloring of their hands gets darker.  I noticed their 'dirty hands' at about 2+" svl. Males have a flat rear. Males also develop nuptial pads; this is when their hands and forearms turn black. Nuptial pads help them hold onto the slippery females during mating. My males were showing the pads when they were 2" svl.    Go to ACF Mating to see pictures of the differences, and mating. Mating The frogs usually mate at night. You can wake up the next morning to find hundred of eggs all over the tank. They cling to everything!  Remove any unwanted eggs and simply flush. Differences between African CLAWED and African DWARF frogs: *How many times have you saw little aquatic frogs in a pet store , and were told they were dwarfs? Well, there is one way to tell.... African DWARF frog- The dwarf has WEBBED front hands. This frog never gets over 2" long.    It's care is similar to the clawed frog, but i find they are harder to care for. Their life span is a fraction of that of the clawed frog. African CLAWED frog - The clawed frog DOES NOT HAVE WEBBED HANDS. These frogs get considerably bigger, and are a much hardier frog. These can live up to 25 years! Illegal in some states! Xenopus are illegal in some states. This is because some have been released, or escaped into the wild, and wiped out native species. I found a list -inside & outside the U.S. - where they are illegal in @ http://aquaticfrogs.tripod.com: Arizona California Colorado Hawaii Kentucky Louisiana Nevada New Jersey North Carolina Oregon Utah Virginia Washington State ....in these places,  you must have a permit to own, transport or sell them. * I was recently given new information by Rachel - (http://aquaticfrogs.tripod.com) that ACF are NOT illegal in Canada, most importantly, Brunswick. This is according to the New Brunswick Regulation 92-74, under the Fish and Wildlife Act (O.C. 92-416).  You can find more information regarding this regulation on her site.