Crossword Genius

Spy desert rodent (4,3)

Ross

I believe the answer is:

mole rat

'rodent' is the definition.
(mole rat is a kind of rodent)

'spy desert' is the wordplay.
'spy' becomes 'mole' (mole is a kind of spy).
'desert' becomes 'rat' (abandon treacherously).
'mole'+'rat'='MOLE-RAT'

I've seen this clue in The Times.
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