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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3533a77a30c415f063d80d9dea734c7702cef182d1dd0b54b19d075d592efe72' 
  AND token = 'X1mfLCvzntDNi7LY8opOEK7U18b5jSyzS0NPiafBDQk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

Explain
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE								Impossible WHERE noticed after reading const tables