SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'be94cab91127aafbbb6fa6f3af5105dc95bffab165b9ebfea1a3b1e5c286e66b' 
  AND token = 'Xeg+B5USehEUR9iOcmllwtbwSrKsCIqe7Bpo3xJc7pg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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