SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f74213a4e24b520c146c2cd491b2cf47848f786823551d552b1dbb6efd9f7b46' 
  AND token = 'n/FMoCV1j9dDWsFZdquhIh1UbE6HzdKLlOKtZn73lV8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

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