prototherian - primitive oviparous mammals found only in Australia and Tasmania and New Guinea

echidna, spiny anteater, anteater - burrowing spine-covered monotreme of Australia having a long snout and claws for hunting ants and termites

echidna, spiny anteater, anteater - New Guinea echidnas

duck-billed platypus, duckbilled platypus, Ornithorhynchus anatinus, platypus, duckbill - small densely furred aquatic monotreme of Australia and Tasmania having a broad bill and tail and webbed feet; only species in the family Ornithorhynchidae