The Platypus Gugula Erstwilder Brooch

The Platypus Gugula Erstwilder Brooch A tail of an beaver ,a bill of a duck, I lay eggs ,and have a poison sting very extreme
I have web feet and swim alot, my place of abode a hole in a river bank or stream
Australians southern east coast my home, an animal oddity, like no other, a monotreme
An cute Aussie mate a brooch to wear all day, a souvenir to take home with you