SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eaa61c0ddee59c0e1090a55b373fdaed50e0bdf6f5a317ae2525d55264829aae' 
  AND token = 'dGtLN+YnSOLcnKFiVRLsDm/ICLwjnxgusrHqnR0Q22o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}