What is a Platypus?     Facts about the Platypus     Platypus venom causes pain in humans:     How is pain caused in humans?     What  makes platypus venom unique?     Current knowledge on Platypus venom     References

    A platypus Ornithorhynchus anatinus is a vertebrate and it is a mammal.  However, it is a very bizarre and abnormal mammal.  A better description would be that it is more like a collage of different classes of species in the animal kingdom.  The platypus has a coat of fur, nurses its young and is considered a warm blood animal even though its normal body temperature is a very low 32 degrees Celsius.  The platypus also possess traits that are not associated with the mammalian class at all.  The platypus has a beak that resembles a duck's bill, and it does not give live birth like all other mammals; it lays eggs like a bird or reptile.  Additionally, the male and juvenile female platypuses have a venomous spur on each of their hind legs, which is unique because the platypus and echidna are the only two known venomous mammals in the world. The platypus is found only on the east coast of Australia and on the southern Australian island of Tasmania. ( Picture below)
 

The pictures above are courtesy of <http://www,platypus.org>