SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '045d48a8569281a4b06c4ae4cd20cf3ea59e4319366a5ffac260e612d1d1d6dd' 
  AND token = 'mNix4WTRXK5y8v35Viza2sbT6lfJX7Alo+JPgK8Ov0A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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