SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd447573e667f94caa672a8f78fc9f03090f918cb6fd019fc9d702334bb958f8b' 
  AND token = 'GIV1bgz8f1TGM1KDFpWx5ZlshUQE5up94OFVZ2JxjZY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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