monotreme(redirected from Ornithodelphia)
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Related to Ornithodelphia: Metatheria
A member of the order Monotremata.
Any of various egg-laying mammals of the order Monotremata of Australia and New Guinea, whose only living members are the platypus and the echidnas.
mon′o·trem′a·tous (-trĕm′ə-təs) adj.
monotremeany mammal of the primitive subclass Monotremata, including the duck-billed platypus and spiny anteater. Monotremes differ from other mammals in laying eggs, and in having a single opening (CLOACA) for the passage of eggs or sperm, faeces and urine. They inhabit Australia and New Guinea.
a member of the animal order of Momotremata, the egg-laying mammals. Includes only two species, the duck-billed platypus and the spiny anteater.