Crossword Genius

Perhaps seal a tiny creature in a hard covering (4)

Ross

I believe the answer is:

pupa

'tiny creature in a hard covering' is the definition.
(insect in a hard cover)

'perhaps seal a' is the wordplay.
'perhaps seal' becomes 'pup' (pup can mean a young seal).
'pup'+'a'='PUPA'

(Other definitions for pupa that I've seen before include "Stage of an insect's development" , "A chrysalis as of butterfly" , "Phase of insect life" , "One is growing" , "creepy-crawly" .)

I've seen this clue in The Times.
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