SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a7028f56d083746a87c0d629cb15dabd0a6aada064f92e9554a742be8707f6ec' 
  AND token = 'rqiuaG4A3aP4Y3qov+M4djw8a+zuUlb4NwRdEM7/f2o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

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