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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d8feacb9d5ba08dd4b05cfb21b9a70904075aa6e8957430a6facc3788987447' 
  AND token = '6MJT3pSjr4AeTzG6lyOGrmFh2gaaP1nw4J4aIKdxTJY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

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