The one dollar coin denomination (written as $1) was introduced in Australia in 1984, replacing the earlier banknotes. The original reverse design by Stuart Devlin on circulating coins has not been changed since its introduction. The denomination is also often used to issue circulating commemorative coins with various reverses.
The denomination is also used by both the Royal Australian Mint and the Perth Mint to issue an extensive range of collector coins which are legal tender in Australia but are not intended for circulation - such as this one. The coin is larger than the normal $1 coins.
This coin is part of the Perth Mint's Australian Bush Babies II featuring the babies of various native animals of Australia, and depicts a baby Echidna (the 'II' in the name of the series indicates this is the second year it was issued; the first was in 2011).
Echidnas, sometimes known as spiny anteaters, belong to the family Tachyglossidae in the monotreme order of egg-laying mammals. The four extant species of echidnas and the platypus are the only living mammals that lay eggs and the only surviving members of the order Monotremata. The diet of some species consists of ants and termites, but they are not closely related to the true anteaters of the Americas, which are xenarthrans, along with sloths and armadillos. Echidnas live in Australia and New Guinea.
Echidnas evolved between 20 and 50 million years ago, descending from a platypus-like monotreme. This ancestor was aquatic, but echidnas adapted to life on land.
The coins were issued either in a presentation card on in a PNC. | 
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