Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '741d64dc12b83f30ce30e816543b029d5476ec672fe461e9eceb96ff58cfea37' 
  AND token = 'j3pRjKspbrVUGncyWGclm6fwMilZ1A0ievCXPc2DJRc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

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