SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4bdf4f304bd1299b740a8d60df52ccdb5c957aff0879d86054d06cedfadfbe3b' 
  AND token = 'R2dSy0s8tQPZD519hNG/nqZA3NgJlg++VwodkcHuWCU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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